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Armed and Dangerous
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Posted: 5/29/2011 5:31:40 AM EST
Who has both? What are your thoughts?

This is a cool link to an animation showing both in action (see compare button - bottom right)
http://www.armytimes.com/projects/fl...02_20_carbine/

Do you believe the gas piston is more reliable? Do you think it runs cleaner and cooler? Do you notice a considerable difference in recoil?
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Link Posted: 5/29/2011 5:55:10 AM EST
I'm not the biggest piston gun fan. I have had both in the past and I've owned pretty much all of the piston uppers available. all of the rifles I now own are DI.

I definitely don't think they recoil less and I do not think they are more reliable. They do however prolong the runtime of a suppressed gun.

They are much heavier in the scheme of things. They do run cooler on the BCG...the heat is now contained in the piston housing or gas block. Pistons have more moving parts that can break and I guarantee they will break. I have owned many piston systems and have had a few break. One being the HK416. Parts for repair took almost 6 months.

If I was going to get a piston system today, it would be the Adam's Arms Kit. They license their kit to S&W, Spikes, and Sabre when they were still in biz.

Simple and reliable high quality system with easy parts availability.
-Amateurs do it til they get it right. Professionals do it til they can't get it wrong.-

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Link Posted: 5/29/2011 6:17:07 AM EST
I have some of each.

While some of the hype is up to each person to determine, what I can say with 100% certainty about each is this.

DI:

1. Less chance of carrier tilt and cam pin gouging than piston rifles
2. Generally less expensive than piston rifles of same manufacture.
3. Up to 100% interchangable parts between milspec variants. Pistons are proprietary and not interchangeable for parts between most manufacturers.

Piston:

1. BCG remains cleaner and cooler than in DI by a big a lot. You can shoot 100 rounds rapid fire and pull the BCG and lay it in your bare hand. Still cold. Don't do that with DI.
2. Reliability is questionable of piston over DI if your DI is properly lubed and ran wet. See Pat Rogers reports on this.
3. Piston recoil isn't a lot less, but it has a different impulse. more of a soft push.

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Link Posted: 5/29/2011 6:39:54 AM EST
I've had both...my current one is a Stag 8L...don't really note that it is quieter,more accurate would be a matter of millimeters so who knows...it is bone reliable,runs VERY clean and cooler...the bolt has some anti-tilt features and was designed from the beginning to be used with a piston as opposed to being a modified impingement bolt....as for breaking,keep a spring and pin repair kit around just like with a di gun and you should be fine...basically if you want to shoot get a piston gun,if you want to clean get an impingement gun...

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Link Posted: 5/29/2011 7:20:38 AM EST
I've had both and in the end the "benefits" of the piston guns don't outweigh the issues of parts and interchability. The pistons have more parts, are prone to system failure (carrier tilt) and are heavier. In the end, IMHO, the only real benefit to them is the time saved when cleaning the weapon.

Try getting parts for the system if the company you've entrusted goes out of business. The DI guns are mostly compatable with each other.

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Link Posted: 5/29/2011 7:35:59 AM EST
I have sold a couple of PWS Diablos to folks and they are happy. They have a heavy gas piston that looks more on par with an AK compared to many of the retrofits out there which seem a little fragile or gadgety.

At the end of the day, I run a can on my guns when I shoot them and I believe that if they are more reliable with a can, then they will likely run longer without. I'd happily take either and understand that my go to gun is an AK-74 anyways


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Link Posted: 5/29/2011 9:27:14 AM EST
I have a POF and love the hell out of it. it is a little heaver than a DI ar15.
I would go with a hlgh end manufactured piston system if you decide to buy one.
POF warranty's their systems.
There are several threads on this issue probably in archives by now.

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Link Posted: 5/29/2011 10:32:28 AM EST
I also agree with what was stated above. When buying a piston, but a top tier manufacturer with a warranty. My piston rifles are all made by LMT and LWRC and I couldn't be happier with them. If they ever broke, I am confident both will be around for the long run and parts shouldn't be an issue. LMT has a one piece piston that couldn't be simpler. So I don't expect any problems from them.

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Link Posted: 5/29/2011 11:31:28 AM EST
i have both piston and DI, the piston rifle being less acuate is a myth, a have a Adams Arms mid length that consistantly shoot beer bottle caps at 100 yards, i like both type rifles, but i'm starting to lean towards liking the piston guns more. both run cleaner and have beed 100% reliable. so far i have about 900 rounds through an all Daniel Defense build with an Adams Arms piston system and about 400 round through my other middy AA gun. i do admit that is very few rounds compaired to my Colt M4 that has been my go to gun for years, the only thing that choked the Colt was Tula .

i think both systems will have fan boys as much as haters, if anyone in the Augusta area area wants to shoot any of my rifles to compair, they are welcome too. i read around for a long time before before going the piston route, i wanted something different and now the void has been filled. i'm interested in any other responses on this subject.

for what it's worth, i have had zero carrier tilt or upper receiver wear in the rifles, i look after shooting each time. so far, so good
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Link Posted: 5/29/2011 11:36:27 AM EST
Originally Posted By 400North:
Who has both? What are your thoughts?

This is a cool link to an animation showing both in action (see compare button - bottom right)
http://www.armytimes.com/projects/fl...02_20_carbine/

Do you believe the gas piston is more reliable? Do you think it runs cleaner and cooler? Do you notice a considerable difference in recoil?


i have FSC556 breaks on all my rifles so recoil is not an issue on any of my rifles, the Adams Arms systems i have do run MUCH cleaner abd cooler than DI, so far, the piston rifles have been as reliable as my DI guns. all my rifles have been 100% until i bought Tula, none of my rifles DI or piston will run that crap. any brass i have run has been 100% in any of the rifles.
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Link Posted: 5/29/2011 1:27:59 PM EST
[Last Edit: 5/29/2011 1:36:38 PM EST by panzer]
I have never seen a Direct impingement AR15. its a mislabeling of sorts

However it is a name that caught on, although its not 100% correct, it stuck.

Armalite describes it best,

Tech note #54 from armalite.

Armalite Tech Note #54


FACTS: The AR-15/M16 and the AR-10 family of rifles employ a unique gas powered
operating system patented by Eugene Stoner in the 1950s. This gas operating system
works by passing high pressure propellant gasses tapped from the barrel down a tube and
into the carrier group within the upper receiver, and is commonly but incorrectly referred
to as a “direct impingement” system.

The gas expands within a donut shaped gas cylinder within the carrier. Because the bolt is
prevented from moving forward by the barrel, the carrier is driven to the rear by the
expanding gasses and thus converts the energy of the gas to movement of the rifle’s parts.
The bolt bears a piston head and the cavity in the bolt carrier is the piston sleeve. It is
more correct to call it an “internal piston” system.

Most previous semiautomatic rifles use an “external piston” system operating in a gas
cylinder mounted outside the receiver, but instead attached to the barrel. Propellant
gasses expand within the cylinder and force the piston to the rear. The piston either
contacts a rod that and drives a carrier to the rear (FAL), or are part of, connected to, or
strike a rod segment that passed around the action to cam and move the bolt (M1, M14,
AK- 47, SCAR). In some cases the piston is fixed and the movable cylinder drives the
rod (AR-180).
ADVANTAGES AND DISADVANTAGES: The Stoner system provides a very
symmetric design that allows straight line movement of the operating components. This
allows recoil forces to drive straight to the rear. Instead of connecting or other
mechanical parts driving the system, high pressure gas performs this function, reducing
the weight of moving parts and the rifle as a whole.
In external piston systems, the path of the operating force is mechanically shifted around
the action, resulting in a considerable mass of moving parts moving outside the centerline
of the firearm and producing various torques within the system.

There is a common belief that the external piston operated systems are less accurate than
the Stoner internal piston system because the operating parts start moving while the bullet
is still in the bore. This is not true: Army Ordnance tests conducted in the 1960s revealed
that the bullet is 25 feet out of the bore of the M1 and 15 feet out of the bore of the M14
before any operating part begins to move. It is more likely that the imbalances of the
external piston, operating rod, cylinder, and other parts hanging on the barrel produce
disruptive vibrations as the bullet exits the bore.

Although movement of the operating parts while the bullet is in the bore isn’t apparently
a culprit in reducing the accuracy of external piston systems, the inherent accuracy of the
Stoner internal piston system has been consistently confirmed in competitive shooting. In
all events that allow use of any mechanism the shooter wishes, the Stoner internal piston
system is prevailing. Few competitive shooters use the Garand or Kalashnikov systems,
and none observed now use the FAL system. In American Service Rifle and NRA
competition, the external-piston operated rifles are considered a significant disadvantage.
There is a debate about which system remains cleanest. The internal piston system tends
to leave propellant residue in the receivers, while the external piston systems keep the
residue outside the action in the cylinder. External piston driven systems, however, tend
to allow more external dirt into the action because of the openings required for various
connecting members (operating rod, bolt lugs, etc). Comparison tests of the M16 and the
M-14 before Desert Storm confirmed the superiority of the Stoner system in sand and
dust tests, and recent testing has proven that proper cleaning of either system provides
excellent reliability.

ArmaLite concludes that there is no technical advantage to an external piston system
employing current ammunition. It will likely, however, provide external-piston systems
to the market as customers demand.

As a last note, misuse of the term “direct impingement” to describe the Stoner system is
so common that it has confused the issue. A direct impingement system like that of the
AG-42 Ljungman or the French MAS-49 rifle taps gas at the barrel and passes it into the
receiver in a way similar to the M16, (the source of the confusion) but deposits it into a
small, shallow cup or pocket in the carrier. The gas expands there and drives the carrier
to the rear with relatively little pneumatic advantage. The addition of the Stoner internal
piston system provides significantly more pneumatic advantage to the rifle and little of
the blast of escaping gas at the breech end of the gas tube of the earlier rifles.


Of course this has yet to be proven or said by Costa, Vickers or any other gold dicked shooters, so no one believes it. Just a manufacturer That bought the company that designed it.


But all that aside, The AR is fine like it is. Piston system may have its place for certain needs and be a better mouse trap for certain mice, but not the final solution. The original set up works for just about anything.
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Link Posted: 5/29/2011 1:47:04 PM EST
I have one of the Diasblo uppers which is shown earlier in this thread and it is a very functional and reliable design. I had an LMT MRP but decided to sell it for several reason. Mostly because of weight and the incapatability of parts between the platforms. It was also a fine shooting firearm.

My earlier comments about incompatability is related to the fact that you have LWRC, Adams Arms, LMT, PWS, HK and countless others making piston guns. A large number of htem use different size pistons. Long Stroke, Short Stroke, some operating off of the gas block over the barrel, some attached to the bolt carrier. Their is no consistency in the industry so parts can be an issue. If things stabslize then maybe I will give it another look but until this happens i'm sticking with the DI guns

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Link Posted: 5/30/2011 4:13:19 AM EST
I have both. I have an Osprey in my competition gun and have not had a problem with it. I love the design as it can be switched out in about 10 minutes back to DI, should I ever desire to do so. I did have a DI gun crap the bed on me during a competition, which is what prompted me to go piston in the first place.

I have a DI system on my 6.5 Grendel and will keep it so.

On thing that is markedly different is the amount of time required for cleaning. My piston runs extremely clean and cuts my cleaning time in half for that rifle.


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Link Posted: 5/30/2011 9:27:25 AM EST
[Last Edit: 5/30/2011 9:28:36 AM EST by LARRYG]
Someone beat me to it.
If it's a Colt, it's a copy of an original ArmaLite.

I am not LARRYG36.

Racing is life. Anything that happens before or after is just waiting.

If your AR10 is marked Geneseo, IL, it's still an AR10 no matter what some people say.
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Link Posted: 5/30/2011 9:30:15 AM EST
[Last Edit: 5/30/2011 9:33:47 AM EST by LARRYG]
Originally Posted By panzer:
I have never seen a Direct impingement AR15. its a mislabeling of sorts

However it is a name that caught on, although its not 100% correct, it stuck.

Armalite describes it best,

Tech note #54 from armalite.

Armalite Tech Note #54


FACTS: The AR-15/M16 and the AR-10 family of rifles employ a unique gas powered
operating system patented by Eugene Stoner in the 1950s. This gas operating system
works by passing high pressure propellant gasses tapped from the barrel down a tube and
into the carrier group within the upper receiver, and is commonly but incorrectly referred
to as a “direct impingement” system.

The gas expands within a donut shaped gas cylinder within the carrier. Because the bolt is
prevented from moving forward by the barrel, the carrier is driven to the rear by the
expanding gasses and thus converts the energy of the gas to movement of the rifle’s parts.
The bolt bears a piston head and the cavity in the bolt carrier is the piston sleeve. It is
more correct to call it an “internal piston” system.

Most previous semiautomatic rifles use an “external piston” system operating in a gas
cylinder mounted outside the receiver, but instead attached to the barrel. Propellant
gasses expand within the cylinder and force the piston to the rear. The piston either
contacts a rod that and drives a carrier to the rear (FAL), or are part of, connected to, or
strike a rod segment that passed around the action to cam and move the bolt (M1, M14,
AK- 47, SCAR). In some cases the piston is fixed and the movable cylinder drives the
rod (AR-180).
ADVANTAGES AND DISADVANTAGES: The Stoner system provides a very
symmetric design that allows straight line movement of the operating components. This
allows recoil forces to drive straight to the rear. Instead of connecting or other
mechanical parts driving the system, high pressure gas performs this function, reducing
the weight of moving parts and the rifle as a whole.
In external piston systems, the path of the operating force is mechanically shifted around
the action, resulting in a considerable mass of moving parts moving outside the centerline
of the firearm and producing various torques within the system.

There is a common belief that the external piston operated systems are less accurate than
the Stoner internal piston system because the operating parts start moving while the bullet
is still in the bore. This is not true: Army Ordnance tests conducted in the 1960s revealed
that the bullet is 25 feet out of the bore of the M1 and 15 feet out of the bore of the M14
before any operating part begins to move. It is more likely that the imbalances of the
external piston, operating rod, cylinder, and other parts hanging on the barrel produce
disruptive vibrations as the bullet exits the bore.

Although movement of the operating parts while the bullet is in the bore isn’t apparently
a culprit in reducing the accuracy of external piston systems, the inherent accuracy of the
Stoner internal piston system has been consistently confirmed in competitive shooting. In
all events that allow use of any mechanism the shooter wishes, the Stoner internal piston
system is prevailing. Few competitive shooters use the Garand or Kalashnikov systems,
and none observed now use the FAL system. In American Service Rifle and NRA
competition, the external-piston operated rifles are considered a significant disadvantage.
There is a debate about which system remains cleanest. The internal piston system tends
to leave propellant residue in the receivers, while the external piston systems keep the
residue outside the action in the cylinder. External piston driven systems, however, tend
to allow more external dirt into the action because of the openings required for various
connecting members (operating rod, bolt lugs, etc). Comparison tests of the M16 and the
M-14 before Desert Storm confirmed the superiority of the Stoner system in sand and
dust tests, and recent testing has proven that proper cleaning of either system provides
excellent reliability.

ArmaLite concludes that there is no technical advantage to an external piston system
employing current ammunition. It will likely, however, provide external-piston systems
to the market as customers demand.

As a last note, misuse of the term “direct impingement” to describe the Stoner system is
so common that it has confused the issue. A direct impingement system like that of the
AG-42 Ljungman or the French MAS-49 rifle taps gas at the barrel and passes it into the
receiver in a way similar to the M16, (the source of the confusion) but deposits it into a
small, shallow cup or pocket in the carrier. The gas expands there and drives the carrier
to the rear with relatively little pneumatic advantage. The addition of the Stoner internal
piston system provides significantly more pneumatic advantage to the rifle and little of
the blast of escaping gas at the breech end of the gas tube of the earlier rifles.


Of course this has yet to be proven or said by Costa, Vickers or any other gold dicked shooters, so no one believes it. Just a manufacturer That bought the company that designed it.


But all that aside, The AR is fine like it is. Piston system may have its place for certain needs and be a better mouse trap for certain mice, but not the final solution. The original set up works for just about anything.


And the boss is a former Army Ordnance officer and a competitor, so what does he know.

This also points out that while some think an external piston is the "latest and greatest" thing, it's actually quite old.

And then there is the problem of BCG tilt on a rifle that was not designed from the ground up for it.

The AR180/18, for instance, has two rails that the BCG rides in order to eleviate this problem, while most external piston uppers for ARs do not have that.
If it's a Colt, it's a copy of an original ArmaLite.

I am not LARRYG36.

Racing is life. Anything that happens before or after is just waiting.

If your AR10 is marked Geneseo, IL, it's still an AR10 no matter what some people say.
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Link Posted: 5/30/2011 4:22:18 PM EST
It's a fix to a perceived (read: non-existent) problem that has itself led to even more problems.

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Link Posted: 5/30/2011 6:04:53 PM EST
I have talked to people who have the piston system. Most of them like it, but they said they sometimes had problems getting replacement parts. I have never had problems with the gas system or getting replacement parts. That's IMHO.

Mike

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Link Posted: 5/30/2011 8:45:08 PM EST
The AR-15 is a damn fine weapon. The gas piston idea seems good and I have no qualms with it, but I don't see the point in spending the extra money on it. The main advantage I see is that it keeps the bolt carrier group cooler, but as a result the forward hand guards absorb that heat and the rifle is slightly heavier. I have a DI AR and a gas piston 5.56 (not an AR) they both run spectacular and I love them both.

Of the relatively few malfunctions I have seen on the AR-15 system, most of which were on very old M16s I can tribute zero of them to the gas system and a great majority were cause by bad magazines.

Finals thoughts: gas pistons are cool rifles and I can see why people like them, but I would take the extra cash and spend it on high quality magazines. That will help your weapon systems reliability more than anything else, In my opinion.

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Link Posted: 5/31/2011 2:53:54 AM EST
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Link Posted: 5/31/2011 7:46:23 AM EST
Originally Posted By BookHound:
Originally Posted By votefromrooftops:
i have both piston and DI, the piston rifle being less acuate is a myth, a have a Adams Arms mid length that consistantly shoot beer bottle caps at 100 yards,



Funny, that isn't my experience. I've shot a lot of different piston guns including a batch (eight to be exact) that were converted from DI to piston (Adams kits). The rifles were all shot for groups prior to the conversion then again after. While the difference wasn't huge there was a noticeable increase in group size after the conversion. Now, that is still a small sample so it might be meaningless info in the grand scheme of things. For the record the rifles were a mic of RRA, Bushmaster and LMT factory guns. The fast is a piston gun has more moving parts and a harder recoil. The movement of those parts can adversely affect accuracy.

Just curious but what optic are you running on your beer bottle cap rifle? What ammo? What barrel? Define the consistency of your accuracy for me. If I stuck ten caps on an IDPA target at 100-yards, how many would you hit do you think? Did you ever try the rifle before the Adams kit was installed to see if there was a difference? Not busting your balls so please don't take that way. This kind of info helps us all.


I agree with Tod's comments. I've shot a lot of piston guns. I've also shot a lot of DI guns with short, suppressed barrels and have had excellent results in them being reliable. I fail to see the need to adopt a piston system at this time for my personal needs. But, like Tod, if I were to go with one kit it would be the Adams.

Mark


Mark, no problem, the rifle in question is as Adams Arms factory upper, mid length 16" with a FSC556, the lower is Daniel Defense lower, with DD LPK and polished trigger, magpul ACS stock, and magpul MOE pistol grip. the buffer is a Spikes T2, the barrel is a medium weight chambered in 556, that is CL, Chrome bore. the optic is a Weaver super slam 1.5x6x24 30mm on a Larue spr 1.5 mount. the ammo was PMC 55gr fmj. i was shooting with a freind on his farm, my buddy is seriously an awesome shooter, that's why i wanted someone other than myself to shoot it, i had shot the rifle only once before to function test everything and zero the scope. i consider myself fair with a carbine, we shot at his farm at what he said was a 100 yard distance, it looked every bit of that if not a little more. to be completely honest the the rifle would hit 5 out of 10 beer caps if there had been that many. the rifle was shot from a fence to make a more stable shot. there were 6 bud light caps, 3 had holes in them. my friends son, shot one dead center and wanted to keep it, there was also a golf ball that has several rounds through it at that distance. shooting was done at a very slow pace so shots could be well placed. i'm very pleased with the rifle. i do understand that the shooting at my buddies farm was not scientific, but i feel that it was fair for a jack leg like me. i make no claims to be a super sniper or anything like that

i have another piston rifle that is Adams Arms conversion/ Daniel Defense rifle that has an Aimpoint on it, i have it down to about 2 inch group at 30 yards. but any rifle will do that, so that's no big deal. the reason i posted about the "myth" is that people seem almost hostile when it comes to DI vs. piston. everyone says they are heavier, less accurate, more recoil, etc....i agree that some of that is true, i just wanted something different from what i already have. and for a hobbiest like me, i really enjoy having different rifles. as posted earlier, if you or anyone is ever in the area and would like to shoot anything i own, you guys are more than welcome too
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Link Posted: 5/31/2011 5:20:16 PM EST
There is a common belief that the external piston operated systems are less accurate than
the Stoner internal piston system because the operating parts start moving while the bullet
is still in the bore. This is not true: Army Ordnance tests conducted in the 1960s revealed
that the bullet is 25 feet out of the bore of the M1 and 15 feet out of the bore of the M14
before any operating part begins to move. It is more likely that the imbalances of the
external piston, operating rod, cylinder, and other parts hanging on the barrel produce
disruptive vibrations as the bullet exits the bore.


While I agree that the parts just being there is a factor, this fails to explain why the majority of FALs I have seen tests done with yield better groups when fired with the gas plug rotated to the off position.

Understand this does nothing other than prevent gas from contacting the moving parts of the gas system. Those parts are all still there flopping around.

I have a modification I am planning for the FAL to see if it has any affect on accuracy, but I am not talking about it much right now. It will be a simple no-gunsmith install if it works also.

As it turns out, there is a difference in behavior of the gas system of piston driven vs 'whatever-we-want-to-call-the-AR-system' even before the parts start moving.
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Link Posted: 6/4/2011 4:23:29 PM EST
So now that we have established plenty of information non essential to the accuracy of your piston gun. Im still trying to wrap my head around the true measurement of a sub minute of beer cap rifle.

If you had six caps on a board. How many first round hits could you make propped on a fencepost with your Weaver Super Slam 1.5-6 shooting PMC 55gr. FMJ?
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Link Posted: 6/4/2011 4:26:33 PM EST
Thank You Tod for posting that-I was thinking the same thing myself....

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Link Posted: 6/4/2011 5:40:56 PM EST
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Link Posted: 6/4/2011 6:50:17 PM EST
Book.....I think you pretty much know where I'm going with this.

Sometimes folks claims and judgement somewhat become skewed.

Shooting sub minute of beer cap is not easily accomplished with a 1/2 moa capable precision bolt rifle with a 3.5-15 power high end optic while the front of the gun is propped on a quality bipod and the rear of the stock is supported by a bag.

My guess is that multiple shots were probably fired at a specific beer cap and one of those rounds inadvertently impacted the bottle cap. Now said gun is capable of shooting minute of beer cap. And then we haven't even addressed consistency. A truly accurate minute of beer cap rifle should be able to put 3-5 rounds into said beer cap.

I'm not saying the gun in question isn't accurate. I just don't believe it to be as accurate as portrayed at the 100 yards if not more range as specified with sub premium PMC FMJ ammunition.

I also have yet to figure out how the type and brand of stock,grip,lower parts kit,scope mount, blah blah blah has anything to do with what said rifle did.
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Link Posted: 6/4/2011 6:53:25 PM EST
[Last Edit: 6/4/2011 7:02:16 PM EST by robpiat]
OT but White Oak is no longer threading match barrels because of me.

more info herehttp://www.ar15.com/archive/topic.html?b=3&f=118&t=525076

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Link Posted: 6/4/2011 7:01:12 PM EST
Originally Posted By robpiat:
OT but White Oak is no longer threading match barrels because of me.


Way to ruin it for everybody else.

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Link Posted: 6/4/2011 7:37:57 PM EST
Sub-minute of beer cap, lol. I just gotta say it now...

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Link Posted: 6/4/2011 11:49:57 PM EST
How about we just make an event out of it for any future HTF shoots? We could call it the "rooftop MOA of beer cap challenge". It could be a little more fun and not so much punitive. Might need to make the range a little shorter cause my old eyes are not gonna be able to see one that far tho'And for the record I have both types of AR one is a Ruger 556 and the other is a armalite national match upper that Fronut helped me get. the ruger is pretty accurate, but I really like it mostly because it can be adjusted not to blow gas in my face from any NFA attachments. Honestly the DI probably is more accurate, but considering the human torso being the size it is it probably doesn't matter that much within my capabilities.

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Link Posted: 6/5/2011 6:56:29 AM EST
Originally Posted By burke76:
How about we just make an event out of it for any future HTF shoots? We could call it the "rooftop MOA of beer cap challenge". It could be a little more fun and not so much punitive. Might need to make the range a little shorter cause my old eyes are not gonna be able to see one that far tho'And for the record I have both types of AR one is a Ruger 556 and the other is a armalite national match upper that Fronut helped me get. the ruger is pretty accurate, but I really like it mostly because it can be adjusted not to blow gas in my face from any NFA attachments. Honestly the DI probably is more accurate, but considering the human torso being the size it is it probably doesn't matter that much within my capabilities.


I used to have that problem with two of my AR10s when suppressed. I got a SASS gas lock that has "suppressed" and "normal" settings for each rifle and that cured the problem, so you can get an adjustable block for either type.

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Link Posted: 6/5/2011 7:32:59 AM EST
[Last Edit: 6/5/2011 7:56:59 AM EST by votefromrooftops]
deleted, Book sent you an IM
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Link Posted: 6/5/2011 7:45:02 AM EST
[Last Edit: 6/5/2011 7:45:19 AM EST by robpiat]
Originally Posted By 00bullitt:
Originally Posted By robpiat:
OT but White Oak is no longer threading match barrels because of me.


Way to ruin it for everybody else.



John hates silencers. He has been disgusted with me wanting to run a can from day one. He thinks that a can only kill accuracy.

He tested the barrel he sent me and it shot like hell. He then threaded another, had it air gauged by the maker(Forgot who, Shilen maybe) and it shot like hell. His operating theory is that the step down from .875 to the threads makes the barrel bad. I don't know but I have plenty of threaded guns that shoot. Currently he is going to try a new BCG / reciever and see if that's the issue. Its been a long process.

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Link Posted: 6/5/2011 8:16:53 AM EST
Originally Posted By robpiat:
Originally Posted By 00bullitt:
Originally Posted By robpiat:
OT but White Oak is no longer threading match barrels because of me.


Way to ruin it for everybody else.



John hates silencers. He has been disgusted with me wanting to run a can from day one. He thinks that a can only kill accuracy.

He tested the barrel he sent me and it shot like hell. He then threaded another, had it air gauged by the maker(Forgot who, Shilen maybe) and it shot like hell. His operating theory is that the step down from .875 to the threads makes the barrel bad. I don't know but I have plenty of threaded guns that shoot. Currently he is going to try a new BCG / reciever and see if that's the issue. Its been a long process.


Sounds like a problem on the manufacturer's end.

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Link Posted: 6/5/2011 3:04:32 PM EST
It is possible to screw up the bore with a thread job. If it is improperly cut, the stress can open the bore diameter enough to cause problems. One possible option is to put a deep crown on the muzzle to try and remove the expanded bore. Another is to lop off the threads and re-cut them. Is this a thread-on can or one that mounts to an adapter.


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Link Posted: 6/5/2011 4:02:02 PM EST
Originally Posted By BookHound:

I have 10 bottle caps I'll provide at a known, verifiable distance 100-yard range. We can have as many people attend as witnesses as anyone wants. Each cap is worth $100. Ten rounds, ten caps, ten $100 bills. The key here was "consistency" right?

I'm willing to put my money where my mouth is. I'll be shooting my White Oak Armament barrel SPR with Corbon ammo and NF 2.5-10 set to no more than 6-power. Vote, you can shoot your sub-MOA PMC ammo with your Weaver scope. No fence posts. No guessing at range. Shooters get 10 "sight in" rounds. I say we do it within the next month. Should be a fun exercise for everyone. If you aren't that sure of yourself and don't want to risk the payout, we can shoot for something else. Maybe the loser takes a sabatical from the site for a year. I am open to suggestions.


question, do I have to pay your for each bottle cap I miss? (just asking cause I don't have $1000 to give you)

assuming I don't have to pay then I am up for it!!!! only one problem. wife has 4 weeks left till she is going to pop.....what about next sunday the 12th? I think I can get away with out getting in too much trouble.....

to make it more fair...for you....I will also use my WOA 18" and I will leave my scope on 4x but only b/c that is as high as it goes

I got it! lose get's the other person's scope!!!

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and you can burn the whole state down as far as Im concerned. Kalifornia aint got Shit on The Great State of Georgia.
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Link Posted: 6/5/2011 4:23:50 PM EST
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Link Posted: 6/5/2011 4:53:31 PM EST
dang it sounded fun! I just want to see if my WOA barrel is sub MOBC accurate or not....
Originally Posted By ExKalifornian:
and you can burn the whole state down as far as Im concerned. Kalifornia aint got Shit on The Great State of Georgia.
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Link Posted: 6/5/2011 5:17:39 PM EST
Interesting to see the divide. I just wanted a little feedback on the alternate construction and, frankly, to know if the extra $1000 had some merit. Was not expecting the strong opinions. By my count, mostly saying it is not worth it. I decided to find out for myself and ended up getting a LWRC M6A2 and sticking an ACOG on it. While in the shop I had a chance to check out the DD M4 V5 so picked one of those up too. I actually walked away for a week but it called me back. Haunted me. I sold a kidney and went back. That DD is bad ass. Now she just needs some glass.

Thanks for the feedback.
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Link Posted: 6/5/2011 5:38:08 PM EST
Originally Posted By 400North:
Interesting to see the divide. I just wanted a little feedback on the alternate construction and, frankly, to know if the extra $1000 had some merit. Was not expecting the strong opinions. By my count, mostly saying it is not worth it. I decided to find out for myself and ended up getting a LWRC M6A2 and sticking an ACOG on it. While in the shop I had a chance to check out the DD M4 V5 so picked one of those up too. I actually walked away for a week but it called me back. Haunted me. I sold a kidney and went back. That DD is bad ass. Now she just needs some glass.

Thanks for the feedback.


Cough..Cough... Nightforce.... Cough.. 1-4x.... Cough...Cough...

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Link Posted: 6/6/2011 3:45:41 AM EST
Originally Posted By MadcapMagician:
Originally Posted By 400North:
Interesting to see the divide. I just wanted a little feedback on the alternate construction and, frankly, to know if the extra $1000 had some merit. Was not expecting the strong opinions. By my count, mostly saying it is not worth it. I decided to find out for myself and ended up getting a LWRC M6A2 and sticking an ACOG on it. While in the shop I had a chance to check out the DD M4 V5 so picked one of those up too. I actually walked away for a week but it called me back. Haunted me. I sold a kidney and went back. That DD is bad ass. Now she just needs some glass.

Thanks for the feedback.


Cough..Cough... Nightforce.... Cough.. 1-4x.... Cough...Cough...


I think I have a cure for that nasty cough you have there.......

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Link Posted: 6/6/2011 4:28:52 AM EST
Originally Posted By ikickhippies:
Originally Posted By MadcapMagician:
Originally Posted By 400North:
Interesting to see the divide. I just wanted a little feedback on the alternate construction and, frankly, to know if the extra $1000 had some merit. Was not expecting the strong opinions. By my count, mostly saying it is not worth it. I decided to find out for myself and ended up getting a LWRC M6A2 and sticking an ACOG on it. While in the shop I had a chance to check out the DD M4 V5 so picked one of those up too. I actually walked away for a week but it called me back. Haunted me. I sold a kidney and went back. That DD is bad ass. Now she just needs some glass.

Thanks for the feedback.


Cough..Cough... Nightforce.... Cough.. 1-4x.... Cough...Cough...


I think I have a cure for that nasty cough you have there.......
http://longrangesupply.com/images/1_4x24_zerostop.jpg


Perhaps a silly question but what does NF have that eliminates the optical occlusion from incorrect eye relief? The ACOG was desirable because I had instant sight without this issue. I am still working with my NF on the 308 and it seems a constant battle for me to find that perfect distant from my eye to the scope.
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Link Posted: 6/6/2011 6:55:45 AM EST
[Last Edit: 6/6/2011 6:58:13 AM EST by 00bullitt]
Nightforce has what is known as True 1x in their NXS 1-4

The Trijicon is able to acomplish that due to it being a fixed power short focal length scope. You cannot accomplish the short focal length required in a variable powered scope with an erector tube assembly.

Nightforce does have a rather forgiving eyebox though that provides quick acquisition.

ETA: This thread has derailed by biblical proportion. Started as a question about piston guns vs. DI guns. Morphed into accuracy and then into threaded barrels and manufacturer problems. Now we discuss optics in the same thread.
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Link Posted: 6/6/2011 8:05:10 AM EST
Originally Posted By 00bullitt:

ETA: This thread has derailed by biblical proportion. Started as a question about piston guns vs. DI guns. Morphed into accuracy and then into threaded barrels and manufacturer problems. Now we discuss optics in the same thread.


so does this mean the MOBC accuracy test isn't going to happen?

if Sunday won't work I will burn a vacation day (that I was saving for the birth of my son.....) to go! but really she has less than 4 weeks left so let's get this ball moving!
Originally Posted By ExKalifornian:
and you can burn the whole state down as far as Im concerned. Kalifornia aint got Shit on The Great State of Georgia.
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Link Posted: 6/6/2011 8:20:11 AM EST
[Last Edit: 6/6/2011 8:27:33 AM EST by 00bullitt]
Originally Posted By gajeep94yj:
Originally Posted By 00bullitt:

ETA: This thread has derailed by biblical proportion. Started as a question about piston guns vs. DI guns. Morphed into accuracy and then into threaded barrels and manufacturer problems. Now we discuss optics in the same thread.


so does this mean the MOBC accuracy test isn't going to happen?

if Sunday won't work I will burn a vacation day (that I was saving for the birth of my son.....) to go! but really she has less than 4 weeks left so let's get this ball moving!


It is not a test.....it was a challenge to verify validity of a certain claim.

I see where VFR had responded but taken the conversation private. I'm guessing that he may have very well mis stated what he was trying to say as a claim to accuracy. Which is totally understandable.

The true definition of a sub minute of beer cap rifle is a rifle capable of perforating the beer cap on every shot. Not taking 10 shots and finally making contact on the 11th. Taking multiple shots and finally hitting the target is known as an effective cone of fire.

Just sayin.....

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Link Posted: 6/6/2011 8:31:46 AM EST
FWIW...I just returned from the AAC 3-gun match and I had no problem hitting a 10" plate at 405 yds. with my FNH 16s (SCAR-L). It's not an AR15 piston gun, but it is surprisingly accurate.

Piston operating systems do have very good accuracy potential. Put together the correct combination of ammunition, optics, and the skill to use it, and a piston driven rifle will have plenty of accuracy.

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Link Posted: 6/6/2011 9:05:17 AM EST
But all that aside, The AR is fine like it is. Piston system may have its place for certain needs and be a better mouse trap for certain mice, but not the final solution. The original set up works for just about anything.


This.

But if you want one, get one. The above statement works for me because it is true and because I cant afford a piston gun

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Link Posted: 6/6/2011 9:31:25 AM EST
Originally Posted By USSA-1:
FWIW...I just returned from the AAC 3-gun match and I had no problem hitting a 10" plate at 405 yds. with my FNH 16s (SCAR-L). It's not an AR15 piston gun, but it is surprisingly accurate.

Piston operating systems do have very good accuracy potential. Put together the correct combination of ammunition, optics, and the skill to use it, and a piston driven rifle will have plenty of accuracy.

USSA-1


Dude......10" is like almost 3 times larger than sub minute of beer cap.

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Link Posted: 6/6/2011 9:32:17 AM EST
[Last Edit: 6/6/2011 9:32:49 AM EST by gajeep94yj]
yea but it was at 400 yards. so it would only be ~2" at 100 yards so really it's only 2x the MOBC rating right?
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and you can burn the whole state down as far as Im concerned. Kalifornia aint got Shit on The Great State of Georgia.
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Link Posted: 6/6/2011 9:39:07 AM EST
[Last Edit: 6/6/2011 9:52:44 AM EST by 00bullitt]
Originally Posted By gajeep94yj:
yea but it was at 400 yards. so it would only be ~2" at 100 yards so really it's only 2x the MOBC rating right?


Thats why I included the word "almost".

For educational purposes.....a minute of angle at 100 yards equates to 4" at 400 yards. So a 10" plate would be 2.5moa larger than the 4" a beer cap(roughly an inch) would represent at 400 yards. Which in term is "almost" 3 inches.

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Link Posted: 6/6/2011 10:06:45 AM EST
[Last Edit: 6/6/2011 10:08:35 AM EST by gajeep94yj]
Originally Posted By 00bullitt:
Originally Posted By gajeep94yj:
yea but it was at 400 yards. so it would only be ~2" at 100 yards so really it's only 2x the MOBC rating right?


Thats why I included the word "almost".

For educational purposes.....a minute of angle at 100 yards equates to 4" at 400 yards. So a 10" plate would be 2.5moa larger than the 4" a beer cap(roughly an inch) would represent at 400 yards. Which in term is "almost" 3 inches.



I was just messing with you.....

BTW I just found VFR bottle cap he was shooting at! apparently he sent it to Newark!


http://www.nj.com/news/index.ssf/2009/05/pabst_blue_ribbon_bottle_resur.html

so knowing this, bookhound the challenge is accepted!
Originally Posted By ExKalifornian:
and you can burn the whole state down as far as Im concerned. Kalifornia aint got Shit on The Great State of Georgia.
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Link Posted: 6/6/2011 10:16:44 AM EST
Originally Posted By gajeep94yj:
Originally Posted By 00bullitt:
Originally Posted By gajeep94yj:
yea but it was at 400 yards. so it would only be ~2" at 100 yards so really it's only 2x the MOBC rating right?


Thats why I included the word "almost".

For educational purposes.....a minute of angle at 100 yards equates to 4" at 400 yards. So a 10" plate would be 2.5moa larger than the 4" a beer cap(roughly an inch) would represent at 400 yards. Which in term is "almost" 3 inches.



I was just messing with you.....

BTW I just found VFR bottle cap he was shooting at! apparently he sent it to Newark!
http://blog.nj.com/ledgerupdates_impact/2009/05/large_Pabst%20blue%20ribbon%20bottle%20cap.JPG

http://www.nj.com/news/index.ssf/2009/05/pabst_blue_ribbon_bottle_resur.html

so knowing this, bookhound the challenge is accepted!


Funny! I was just looking for the same thing!

I'll do it if I can shoot at these...






"...... the right of the people to keep and bear arms shall not be infringed."
^ Why is that so effing hard for some people to understand....
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