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brian41527
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Posted: 4/21/2009 6:54:18 PM
I have been looking at a gas piston ar. Are they really worth the extra price? What are the pros and cons of them, what is the purpose of a gas system. Sorry, it's probably a dumb question, but im a newbie.
ftwm

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Posted: 4/21/2009 6:58:39 PM
[Last Edit: 4/21/2009 7:02:21 PM by ftwm]
And we're off...

I don't understand the piston craze.

I also don't understand the people who jealously defend them.

Gas tubes do exactly what they are supposed to, and they cost $10.

I will never, ever consider a piston unless I build a suppressed SBR. Which will never happen.

ETA: READ THIS THREAD if you want to understand how direct impingement works.
COMMAND450
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Posted: 4/21/2009 7:11:02 PM
I see no reason for one, myself and would like to know(like the op) .......what is to be gained by installing one?

I have a good friend, that has been buying and selling AR's for over 30 years. He also see's no need for one either.
Strongbow
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Posted: 4/21/2009 7:18:01 PM
Originally Posted By brian41527:
I have been looking at a gas piston ar. Are they really worth the extra price? What are the pros and cons of them, what is the purpose of a gas system. Sorry, it's probably a dumb question, but im a newbie.


I own DI AR's and a Piston AR. ALL my AR's work fine for what I use them.

Other than ease of cleaning, it's unlikely any of us would realize any real benefit from using a piston AR.

Piston on AR's shine in SBR, Suppressed and Full Auto applications. Their use for semi-auto guns in less strenuous applications is debatable.

Are they WORTH the extra price? Only you can answer that. If you do one of the above, maybe.

If you're just curious... maybe. I'll be honest and say I got mine because I was curious, and the overall quality of teh rifle and components are excellent. But for now, my Colt 6920 is my go-to gun.
damcv62
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Posted: 4/21/2009 7:28:05 PM
Where they shine is the SBR's, full autos, and guns you run suppressed. Seeing as I do all three, its worth it to me. I wouldn't get a piston in a barrel longer then 11.5", or for a gun I didn't plan to use a can on. You really loose the benfits of the piston on them.
wengv
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Posted: 4/21/2009 7:37:10 PM
gas piston system does run cleaner. With current $400+ price tag, you may well buy a true gas piston rifle like an AK.

Gas impingement has been running well for over 40+ years. If it had not worked, it would have been replaced with other systems already.
AddaxTactical
AR15 GAS PISTON ZOMBIE KILLER
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Posted: 4/24/2009 3:49:04 AM
The DI gas system is a great system, but it is not optimal for the short Carbine set up (16" barrel ength and shorter).

As much as the M4 Carbine is really liked and well used, it is more prone to carbon fouling due to the short Carbine gas system, which increases the chances of jams or bolt carrier seizure, which makes it much more maintenance intensive.

The growing popularity with Piston Driven AR's or Gas Piston Uppers (especially in Carbine applications) is that they are not maintenance intensive compared to the DI Gas System since the Piston Systems eliminates the Carbon Fouling and Heat related issues in the upper receiver, and the bolt carrier group.

This reduces or virtually elimates the chances of Jams or Bolt Carrier Seizure during operation, due to any sort of Carbon Fouling, since the bolt and upper receiver are kept clean and cool..

Both Piston and DI Gas Systems have different and optimal application/uses, and both are designed for different types of users.





"In any moment of decision, the best thing you can do is the right thing, the next best thing is the wrong thing, and the worst thing you can do is nothing". TR
SOC
"Sarg... I'm Crazy, not stupid."
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Posted: 4/24/2009 4:36:06 AM



MGI: Can your AR do this?
Saiga: Can your 12 gauge do this?
LAR Grizzly: Can you 1911 do this?
Originally Posted By Aimless: They'd be so deep up your ass they'd be looking out your nose. Dumbass.
vicious_cb
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Posted: 4/24/2009 6:15:33 AM
[Last Edit: 4/24/2009 6:16:01 AM by vicious_cb]
Originally Posted By AddaxTactical:
The DI gas system is a great system, but it is not optimal for the short Carbine set up (16" barrel ength and shorter).

As much as the M4 Carbine is really liked and well used, it is more prone to carbon fouling due to the short Carbine gas system, which increases the chances of jams or bolt carrier seizure, which makes it much more maintenance intensive.

The growing popularity with Piston Driven AR's or Gas Piston Uppers (especially in Carbine applications) is that they are not maintenance intensive compared to the DI Gas System since the Piston Systems eliminates the Carbon Fouling and Heat related issues in the upper receiver, and the bolt carrier group.

This reduces or virtually elimates the chances of Jams or Bolt Carrier Seizure during operation, due to any sort of Carbon Fouling, since the bolt and upper receiver are kept clean and cool..

Both Piston and DI Gas Systems have different and optimal application/uses, and both are designed for different types of users.







A 16" with a midlength gas system eliminates all the problems with carbine length gas systems. There is no need for a piston set up if you can get a middy on a 16" barrel.
cmjohnson
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Posted: 4/24/2009 9:25:46 AM
I've mentioned this before, but Reed Knight doesn't even believe that gas piston systems are right for the AR platform, and you probably know that Mr. Knight had
a bit more than a passing acquaintance with Eugene Stoner, inventor of the AR system.


Upon careful evaluation, it's apparent that gas piston systems are wrong for the AR platform. Examine the functional dynamics of how the bolt system operates
in the direct impingement system. The gases are directed through the gas tube, through the snorkel, into the chamber BEHIND the bolt in the bolt carrier, and gas pressure forces
the bolt FORWARD, ensuring that it remains fully closed and in battery, while at the same time starting the carrier on its rearward journey.

With a gas piston system, there is no gas-assisted pressure on the bolt to keep it in battery while chamber pressures taper off.

Also, with the direct impingement system, the action of the gas pressure on the bolt and carrier is straightline axial force. The bolt and carrier are not
subject to bending, twisting or torqueing forces and neither is the upper receiver.

With a gas piston system, the off-axis thrust of the piston on the top section of the carrier results in heavy downward pressure on the rear bearing surfaces
of the bolt carrier, and hence faster wear on them, plus on the contacting surfaces of the upper receiver. The entire carrier system is being forced
downward at the rear in a bending movement. This is hardly optimal.


Gas piston sytems for ARs look like a good idea until you stop and analyze how the system on an AR actually operates.


CJ


"Now they will know why they are afraid of the dark.
Now they will learn why they fear the night."....Thulsa Doom

"My body is a temple."
"No, it's an amusement park. Have a beer."
Texkaw
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Posted: 4/24/2009 9:41:37 AM
[Last Edit: 4/24/2009 9:43:20 AM by Texkaw]
For those of us who are driven to keep our weapons well oiled and spotless, and still like to shoot, a piston gun is well worth it IMO. Hours of cleaning saved. Don't know about the off axis thing on a AR15, but the Sig556 works just fine imo. Then again it was designed as a piston gun from it's inception and has a 55x upper.
Cohibra45
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Posted: 4/24/2009 10:14:05 AM
Originally Posted By brian41527:
I have been looking at a gas piston ar. Are they really worth the extra price? YES!!! What are the pros and cons of them, what is the purpose of a gas system. Pros like them, Cons don't!!! Sorry, it's probably a dumb question, but im a newbie.




Since everyone else here is giving their own 'OPINION', there's mine!!! I actually have one...........LMT MRP CQB Piston. I don't have carrier tilt!!! I don't have unusual wear anywhere I can see!!!! It runs well and is more accurate than I am!!! It is definitely easy to clean and doesn't require that 'wet' look!!!!!

Anyone else that has one can speak up now!!! All the rest can keep blowing hot air (gases just like in your own DI version) for experience!!!
God Bless and good shootin'!!!
SOC
"Sarg... I'm Crazy, not stupid."
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Posted: 4/24/2009 10:37:41 AM
Originally Posted By Cohibra45:
Originally Posted By brian41527:
I have been looking at a gas piston ar. Are they really worth the extra price? YES!!! What are the pros and cons of them, what is the purpose of a gas system. Pros like them, Cons don't!!! Sorry, it's probably a dumb question, but im a newbie.




Since everyone else here is giving their own 'OPINION', there's mine!!! I actually have one...........LMT MRP CQB Piston. I don't have carrier tilt!!! I don't have unusual wear anywhere I can see!!!! It runs well and is more accurate than I am!!! It is definitely easy to clean and doesn't require that 'wet' look!!!!!

Anyone else that has one can speak up now!!! All the rest can keep blowing hot air (gases just like in your own DI version) for experience!!!


Do you also own a DI AR?
MGI: Can your AR do this?
Saiga: Can your 12 gauge do this?
LAR Grizzly: Can you 1911 do this?
Originally Posted By Aimless: They'd be so deep up your ass they'd be looking out your nose. Dumbass.
jhud
theres no way to control it, its totally automatic
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Posted: 4/24/2009 10:45:52 AM
Dont even bother with a conversion.
Any manufacturer who relies on selling conversions is going to be broke in a few years. The owners of their conversions terrible idea will be stuck with a rhino.

If you want to hear a GP conversion failure story, call me on a friday night and be prepared to hear a man rant for 30 minutes.
The mfg did return my $, andlet me keep the crappy POS parts which i sold instead of tossing into the Atlantic Ocean. I literally considered driving to the Atlantic Ocean and doing it.

It's not paranoia if there really is somebody after you.
---------------------------------------------------------------

Adrenaline - Arfcom's drug of choice
cmjohnson
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Posted: 4/24/2009 11:28:18 AM
People who are overly concerned about how clean their rifle is should avoid joining the military. That obsessive/compulsive disorder
will get you killed in the sandbox. Your rifle is a tool. All tools are meant to get a little dirty. Shoot it, have fun, and don't worry
about a little dirt in it. Save the cleaning for when you get home, after dinner. The cleanliness issue is a bogus argument for
the gas piston. It's right up there with the guy who spends 25,000 dollars dressing up his 4x4 and you ask him, "So how does
it do in the mud?" and his answer is " ...M...m...m...m....MUD???? " Kinda silly when you stop and think about it.

If you have a gas piston upper, you DO have carrier tilt, PERIOD. Off-axis thrust guarantees it, by simple physics.
That WILL result in accelerated wear in the rear of the upper's bore and on the bearing surfaces on the bottom
of the carrier. Plus you're possibly in danger of experiencing problems associated with shell extraction while chamber
pressures are still high, as a gas piston system doesn't hold the bolt in battery for that extra millisecond.

A gas piston system is not an improvement on the AR15 action. It introduces more potential problems than it solves.

It's a solution to a problem that doesn't exist.


CJ




"Now they will know why they are afraid of the dark.
Now they will learn why they fear the night."....Thulsa Doom

"My body is a temple."
"No, it's an amusement park. Have a beer."
ftwm

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Posted: 4/24/2009 11:55:49 AM
Originally Posted By Texkaw:
For those of us who are driven to keep our weapons well oiled and spotless, and still like to shoot, a piston gun is well worth it IMO. Hours of cleaning saved. Don't know about the off axis thing on a AR15, but the Sig556 works just fine imo. Then again it was designed as a piston gun from it's inception and has a 55x upper.


Hours of cleaning? You do realize that piston guns get dirty too, right? I don't care if my rifle is spotless. I care if it goes bang every time I pull the trigger. So far, direct impingement has never failed me.

I've gone HUNDREDS of rounds before cleaning, and I know guys who have taken carbine classes and gone a couple of thousand rounds, while doing little more than oiling up the carrier.
Your proctologist called, he found your head.
Cohibra45
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Posted: 4/24/2009 12:36:58 PM
Originally Posted By cmjohnson:
People who are overly concerned about how clean their rifle is should avoid joining the military. That obsessive/compulsive disorder
will get you killed in the sandbox. Your rifle is a tool. All tools are meant to get a little dirty. Shoot it, have fun, and don't worry
about a little dirt in it. Save the cleaning for when you get home, after dinner. The cleanliness issue is a bogus argument for
the gas piston. It's right up there with the guy who spends 25,000 dollars dressing up his 4x4 and you ask him, "So how does
it do in the mud?" and his answer is "...M...m...m...m....MUD????" Kinda silly when you stop and think about it.

If you have a gas piston upper, you DO have carrier tilt, PERIOD. Off-axis thrust guarantees it, by simple physics.
That WILL result in accelerated wear in the rear of the upper's bore and on the bearing surfaces on the bottom
of the carrier. Plus you're possibly in danger of experiencing problems associated with shell extraction while chamber
pressures are still high, as a gas piston system doesn't hold the bolt in battery for that extra millisecond.

A gas piston system is not an improvement on the AR15 action. It introduces more potential problems than it solves.

It's a solution to a problem that doesn't exist.


CJ







CJ,

You do know the difference between fact and theory don't you.......Facts are PROVEN and theory is just SPECULATION due to arithmetic, physics, etc... Kinda like the good ol' evolution theory..........people all the time think that just because it seems right on paper, it's right. However, when 'TESTED', good ol' evolution theory doesn't hold water!!!

So I have to ask if you have personally tested or owned a piston AR??? I have and I can tell you by OBSERVATION that I don't have carrier tilt!!!

I really don't care that you can show me the axial rotation of the bolt by the operating rod theoretically induces tilt/wear..........In REAL LIFE, mine does not show wear!!! LMT spent over 2 years of research and development, tens of thousands of rounds, and countless thousands of dollars in REAL TESTING!!!!!!! Where's your REAL TESTING???? Any more is just what I stated in my last post............HOT GASES SPEWING FORTH FROM AN ORIFACE!!!
God Bless and good shootin'!!!
vicious_cb
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Posted: 4/24/2009 12:43:39 PM
Originally Posted By Cohibra45:
Originally Posted By cmjohnson:
People who are overly concerned about how clean their rifle is should avoid joining the military. That obsessive/compulsive disorder
will get you killed in the sandbox. Your rifle is a tool. All tools are meant to get a little dirty. Shoot it, have fun, and don't worry
about a little dirt in it. Save the cleaning for when you get home, after dinner. The cleanliness issue is a bogus argument for
the gas piston. It's right up there with the guy who spends 25,000 dollars dressing up his 4x4 and you ask him, "So how does
it do in the mud?" and his answer is "...M...m...m...m....MUD????" Kinda silly when you stop and think about it.

If you have a gas piston upper, you DO have carrier tilt, PERIOD. Off-axis thrust guarantees it, by simple physics.
That WILL result in accelerated wear in the rear of the upper's bore and on the bearing surfaces on the bottom
of the carrier. Plus you're possibly in danger of experiencing problems associated with shell extraction while chamber
pressures are still high, as a gas piston system doesn't hold the bolt in battery for that extra millisecond.

A gas piston system is not an improvement on the AR15 action. It introduces more potential problems than it solves.

It's a solution to a problem that doesn't exist.


CJ







CJ,

You do know the difference between fact and theory don't you.......Facts are PROVEN and theory is just SPECULATION due to arithmetic, physics, etc... Kinda like the good ol' evolution theory..........people all the time think that just because it seems right on paper, it's right. However, when 'TESTED', good ol' evolution theory doesn't hold water!!!

So I have to ask if you have personally tested or owned a piston AR??? I have and I can tell you by OBSERVATION that I don't have carrier tilt!!!

I really don't care that you can show me the axial rotation of the bolt by the operating rod theoretically induces tilt/wear..........In REAL LIFE, mine does not show wear!!! LMT spent over 2 years of research and development, tens of thousands of rounds, and countless thousands of dollars in REAL TESTING!!!!!!! Where's your REAL TESTING???? Any more is just what I stated in my last post............HOT GASES SPEWING FORTH FROM AN ORIFACE!!!


Its hard to take you seriously after reading this...
Cohibra45
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Posted: 4/24/2009 1:19:10 PM
Originally Posted By vicious_cb:
Originally Posted By Cohibra45:
Originally Posted By cmjohnson:
People who are overly concerned about how clean their rifle is should avoid joining the military. That obsessive/compulsive disorder
will get you killed in the sandbox. Your rifle is a tool. All tools are meant to get a little dirty. Shoot it, have fun, and don't worry
about a little dirt in it. Save the cleaning for when you get home, after dinner. The cleanliness issue is a bogus argument for
the gas piston. It's right up there with the guy who spends 25,000 dollars dressing up his 4x4 and you ask him, "So how does
it do in the mud?" and his answer is "...M...m...m...m....MUD????" Kinda silly when you stop and think about it.

If you have a gas piston upper, you DO have carrier tilt, PERIOD. Off-axis thrust guarantees it, by simple physics.
That WILL result in accelerated wear in the rear of the upper's bore and on the bearing surfaces on the bottom
of the carrier. Plus you're possibly in danger of experiencing problems associated with shell extraction while chamber
pressures are still high, as a gas piston system doesn't hold the bolt in battery for that extra millisecond.

A gas piston system is not an improvement on the AR15 action. It introduces more potential problems than it solves.

It's a solution to a problem that doesn't exist.


CJ







CJ,

You do know the difference between fact and theory don't you.......Facts are PROVEN and theory is just SPECULATION due to arithmetic, physics, etc... Kinda like the good ol' evolution theory..........people all the time think that just because it seems right on paper, it's right. However, when 'TESTED', good ol' evolution theory doesn't hold water!!!

So I have to ask if you have personally tested or owned a piston AR??? I have and I can tell you by OBSERVATION that I don't have carrier tilt!!!

I really don't care that you can show me the axial rotation of the bolt by the operating rod theoretically induces tilt/wear..........In REAL LIFE, mine does not show wear!!! LMT spent over 2 years of research and development, tens of thousands of rounds, and countless thousands of dollars in REAL TESTING!!!!!!! Where's your REAL TESTING???? Any more is just what I stated in my last post............HOT GASES SPEWING FORTH FROM AN ORIFACE!!!


Its hard to take you seriously after reading this...



I understand cb.....It was just hard to take CJ seriously when it seems that he doesn't have anything other than opinion. I come from a very analytical background and testing is what determines real world conclusions for me. I can look at things all day long and say, it should happen that way, but in testing, the results speak for themselves. I'm not saying I have 'tested/owned' any other brands. I am saying I have an LMT MRP CQB Piston 16" and I've yet had any issues with it.

I too can understand where and how people jump to conclusions. I am also aware of others here that have tried different 'piston kit retrofits' on their ARs and have had very bad results. It's just that there are others here also that have purchased LMTs, LWRCIs, POFs, and Barretts without having any issues. This whole piston vs di argument has gone on way too long and it's tiring to the nth. I am getting a little tired of the rhetoric being parroted here from hearsay, mirrored just to hear yourself talk. New guys come on here all the time looking for sound advice. I give them my experience and I'm lumped in with the 'Piston' crowd. These are all AR's to begin with.......not military M4s or M16s for goodness sake. I would be willing to wager that for the vast majority of people here, they use their rifle as a fun thing to shoot on weekends, or to impress others with their EBR. I, like everyone here was new once and asked a lot of questions. It's up to the people with experience to give their experiences. If you want to give your opinion, then say so......nothing wrong with opinions other than they are just that....opinions/thoughts/hearsay.

I asked a simple question to CJ......Does he or has he ever owned a piston operated AR??? It's not a hard one, but just like politicians, some people don't usually like to have the spotlight shown directly at them.

And for the answer to the other persons question........no, I don't own a DI version of the AR. I have shot them, taken them apart, cleaned them, and enjoyed them. I wanted and waited 8 months for my Piston LMT. The very day I placed my order/got put on the waiting list, I could have purchased the exact same model LMT except it was their DI version. I chose to wait and I chose to spend my money the way I wanted to. Thank God I live in a free America!!!

Now if it's for the 'evolution' comment..........well, all I can say is please do your due diligence before making up your mind.


God Bless and good shootin'!!!
Munition
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Posted: 4/24/2009 1:23:11 PM
Nothing is ever proven in the scientific world my friend. There are only disproven or confirmed hypothesis's. You can only prove a hypothesis false, but you can never prove it, only confirm it. The more you confirm it, the higher probability you have of finding the truth about the situation. Water freezes at 32 degrees F; not a fact, just a confirmed hypothesis. Though its been confirmed enough that we just call it fact in the normal world.

In regards to the piston system, I think its the way to go. I've never shot a piston AR, but I do know that every application that was tested for the replacement of the m16/m4 was a gas system. All the new guns are gas systems, for a reason. I'm sure that reliability and dependability issues have come up, but the Gas system to me obviously has the upper hand. Every new rifle issued to the military today is a gas gun, go figure. The Knights Armament m110, FN SCAR, H&K 416, Bushamster ACR, all gas guns. Though I could be wrong about the m110.
ftwm

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Posted: 4/24/2009 1:34:59 PM
Originally Posted By Munition:
In regards to the piston system, I think its the way to go.


The guys at KAC don't. In fact, they think a short-stroke piston on any M4/M16 is a bad idea.

That's probably why the SR-15/16/25 all come with gas tubes.

I believe pistons have their niche. But putting a piston on a 16" unsuppressed upper on a semi-auto only lower makes no sense to me, at all.
Your proctologist called, he found your head.
_DR
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Posted: 4/24/2009 1:41:11 PM
Originally Posted By cmjohnson:
People who are overly concerned about how clean their rifle is should avoid joining the military.


I was Infantry for 8 years, I can tell you there is a difference between battlefield cleaning and in garrison cleaning.
There is still no excuse for putting away your weapon dirty, that is just plain lazy.
Munition
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Posted: 4/24/2009 1:50:28 PM
Originally Posted By ftwm:
Originally Posted By Munition:
In regards to the piston system, I think its the way to go.


The guys at KAC don't. In fact, they think a short-stroke piston on any M4/M16 is a bad idea.

That's probably why the SR-15/16/25 all come with gas tubes.

I believe pistons have their niche. But putting a piston on a 16" unsuppressed upper on a semi-auto only lower makes no sense to me, at all.


In regards to KAC, I don't have any knowledge on the matter, so I could be wrong and you could be totally right... well put.
cmjohnson
Master Luthier and flight sim junkie
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Posted: 4/24/2009 1:52:28 PM
No, I don't own a gas piston AR nor do I intend to do so.

As for the carrier tilt issue, it can't actually tilt if it doesn't have the clearance to do so, but the force that
would induce that tilt, if room were available, is still there. If you were to place force sensors on two
ARs that started out identical but one was converted to a gas piston system, you WOULD be able to
measure the downward force borne on the rear of the lower receiver, and the carrier. It is certainly
quite a bit more than on the direct gas system example.

I don't have any interest in putting things on my rifle that will cause faster wear on anything.

You're still ignoring the difference in how the bolt is held in place by gas pressure with the direct gas
system, vs. not at all in the piston system. This is potentially an issue of much greater importance
as nobody should feel comfortable firing a 60,000 CUP pressure rifle cartridge with what is essentially
an unsupported bolt!


I formulated my opinion following the highly educated opinion of C. Reed Knight. There is no greater living
authority on the AR-15/M16 platform. If you disagree, go argue with him. You'll lose badly.


CJ
"Now they will know why they are afraid of the dark.
Now they will learn why they fear the night."....Thulsa Doom

"My body is a temple."
"No, it's an amusement park. Have a beer."
Strongbow
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Posted: 4/24/2009 2:09:45 PM
Originally Posted By cmjohnson:
I've mentioned this before, but Reed Knight doesn't even believe that gas piston systems are right for the AR platform, and you probably know that Mr. Knight had
a bit more than a passing acquaintance with Eugene Stoner, inventor of the AR system.


Well, to be fair, Mr Knight has a motive here.... he sells Stoner Rifles. I doubt you'll ever see an SR-XX with a piston on it.

OTOH< I don;t think there's anything wrong with the DI system, per se.


Upon careful evaluation, it's apparent that gas piston systems are wrong for the AR platform. Examine the functional dynamics of how the bolt system operates
in the direct impingement system. The gases are directed through the gas tube, through the snorkel, into the chamber BEHIND the bolt in the bolt carrier, and gas pressure forces
the bolt FORWARD, ensuring that it remains fully closed and in battery, while at the same time starting the carrier on its rearward journey.

With a gas piston system, there is no gas-assisted pressure on the bolt to keep it in battery while chamber pressures taper off.


That's true... but so what? You might expect to see reduced accuracy from a piston system because of this... but we don't. You might expect to see more wear on the bolt lugs. But again, we don't. I am unaware of any problems of Piston AR's coming out of battery too soon. And I suspect the lower operating temperature of the bolt probably offsets the increased friction during the unlock.

Also, with the direct impingement system, the action of the gas pressure on the bolt and carrier is straightline axial force. The bolt and carrier are not
subject to bending, twisting or torqueing forces and neither is the upper receiver.

With a gas piston system, the off-axis thrust of the piston on the top section of the carrier results in heavy downward pressure on the rear bearing surfaces
of the bolt carrier, and hence faster wear on them, plus on the contacting surfaces of the upper receiver. The entire carrier system is being forced
downward at the rear in a bending movement. This is hardly optimal.


Again true... but so what? Such things matter ONLY if they contribute a failure mode. I'm not aware of any problems caused by this. Most of the problems I've heard of with Piston AR's are related the usual engineering bugs you see in a new product... it's a matter of working out the problems.




Gas piston sytems for ARs look like a good idea until you stop and analyze how the system on an AR actually operates.


And yet, they seem to do just fine. Do I think DI AR owners need to scrap 'em and get a Piston AR? No. But there is nothing wrong with pistons on an AR either.




Strongbow
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Posted: 4/24/2009 2:14:36 PM
Originally Posted By Cohibra45:
Originally Posted By cmjohnson:
People who are overly concerned about how clean their rifle is should avoid joining the military. That obsessive/compulsive disorder
will get you killed in the sandbox. Your rifle is a tool. All tools are meant to get a little dirty. Shoot it, have fun, and don't worry
about a little dirt in it. Save the cleaning for when you get home, after dinner. The cleanliness issue is a bogus argument for
the gas piston. It's right up there with the guy who spends 25,000 dollars dressing up his 4x4 and you ask him, "So how does
it do in the mud?" and his answer is "...M...m...m...m....MUD????" Kinda silly when you stop and think about it.

If you have a gas piston upper, you DO have carrier tilt, PERIOD. Off-axis thrust guarantees it, by simple physics.
That WILL result in accelerated wear in the rear of the upper's bore and on the bearing surfaces on the bottom
of the carrier. Plus you're possibly in danger of experiencing problems associated with shell extraction while chamber
pressures are still high, as a gas piston system doesn't hold the bolt in battery for that extra millisecond.

A gas piston system is not an improvement on the AR15 action. It introduces more potential problems than it solves.

It's a solution to a problem that doesn't exist.


CJ







CJ,

Kinda like the good ol' evolution theory..........people all the time think that just because it seems right on paper, it's right. However, when 'TESTED', good ol' evolution theory doesn't hold water!!!


Ahem... THAT is a game you DO NOT want to play (especially in this forum). If you do, contact me and I'll be glad to school you on why evolution is the truth. 'nuff said!


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