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Posted: 6/12/2007 11:09:33 AM EDT
I have heard alot about the 6.5 and the 6.8 and have yet to see either one do anything serious in the matches around the country, although I did hear a marine sniper unit did well at a match out west. I suppose it's time to challange all the 6.5 and 6.8 owners to get in on the badlands tactical sniper match in september that should show if it can cut the mustard, ( better know your dope from 10 to 1000 yds though )
Link Posted: 6/12/2007 11:26:20 AM EDT
[#1]

Quoted:
I have heard alot about the 6.5 and the 6.8 and have yet to see either one do anything serious in the matches around the country, although I did hear a marine sniper unit did well at a match out west. I suppose it's time to challange all the 6.5 and 6.8 owners to get in on the badlands tactical sniper match in september that should show if it can cut the mustard, ( better know your dope from 10 to 1000 yds though )


The 6.8 isn't nor was it intended to be a sniper rifle or to shoot out to 1000 yards.
Link Posted: 6/12/2007 11:41:29 AM EDT
[#2]
Snipe, a guy named Bruce Gordon posted his sniper match results with his 6.5 Grendel on my forum. He did quite well.

The beauty of the Grendel in a "sniper match" format is combining semi-auto capability with low recoil for fast shot recovery in dealing with multiple targets. Sound useful in a military setting?

John

P.S. And what Paul said about the 6.8 also applies to the Grendel. It was not designed to be a dedicated 1000-yard cartridge shoehorned into the AR platform; it was designed to be an AR cartridge with out to 1000-yard capability (if you call matching the performance of Black Hills 7.62 175 SMK Match as having "1000-yard capability").

| 6.5 Grendel: World's Best Combat Cartridge |
Link Posted: 6/12/2007 12:34:27 PM EDT
[#3]
From what I have been able to learn, snipers and long range shooters spend years developing their guns and loads to shoot at matches, and the 6.5 hasn't been around hardly long enough for that process to take place.

There are a few guys shooting them and working them up for that purpose, and one or two are posting, but it is hardly a landslide yet!

The 6.8 just isn't suitable beyond 400-500 yards because you can't load high BC projectiles and make them short enough for the mags.

Bill
Link Posted: 6/12/2007 12:58:00 PM EDT
[#4]

Quoted:

The 6.8 just isn't suitable beyond 400-500 yards because you can't load high BC projectiles and make them short enough for the mags.

Bill


 On that we agree, but no such claims were made by its devolpers that I'm aware of.
No doubt the 6.5 is a better long range ctg. But its not everything its cracked up to be.
Its probrably an adequate 6 to 7 hundred yd ctg. It ain't a 7.62. Its probrably the best long range ctg suitable for a M16. Its just how suitable it is for an M16 that concerns me. M9
Link Posted: 6/12/2007 2:06:44 PM EDT
[#5]

Quoted:

Quoted:

The 6.8 just isn't suitable beyond 400-500 yards because you can't load high BC projectiles and make them short enough for the mags.

Bill


 On that we agree, but no such claims were made by its devolpers that I'm aware of.
No doubt the 6.5 is a better long range ctg. But its not everything its cracked up to be.
Its probrably an adequate 6 to 7 hundred yd ctg. It ain't a 7.62. Its probrably the best long range ctg suitable for a M16. Its just how suitable it is for an M16 that concerns me. M9


Well, NEITHER one is suitable for Full Auto and service in the US military in an M16 from what you have posted, so it doesn't matter much.

I'm just answering his question about why there are so few out there in competition.

As far as the Grendel, we've been through this before, but it essentially matches the .308 data out to 1000 yards or so, and though neither would be my choice at that distance, (I'd prefer the .50 or at least the .338 Lapua) it will shoot and hit things out there at that range. Heck, at 900 yards it hits almost as hard as the 6.8 at 500.

Is it a 1000 yard cartridge? Depends on if you think a .308 is. If you do, then the Grendel is essentially the same. If you don't, well it's not, but that isn't the question, so I don't want to derail this thread anymore than we have, so I'll stay out of it from here on out.

Bill
Link Posted: 6/12/2007 2:53:35 PM EDT
[#6]

The 6.5 Grendel did pretty well at the Snipers Hide Cup 2007. It beat out all but one .308 and finished 18th out of 60. Of course most of this is due to the outstanding shooter (Bruce Gordon) but it does show that the Grendel can be very competitive (it beat out 29 of the 30 .308 rifles there).

Here is the breakdown of the top 20 from a post on SH:

Top 20

1 260 Rem
2 6 mm XC
3 243 Win
4 243 Win
5 243 Win
6 243 Win
7 308 Win
8 260 A I
9 243 Win
10 243 Win
11th 243 Win
12th 260 Rem
13th 6 XC
14th 6 XC
15th 260 Rem
16th 243 Win
17th 243 Win
18th 6.5 Grendal
19th 260 Rem
20th 260 Rem



Totals

308 Win - 30, 260 - 13, 243 - 9, 6xc - 3, 6 x 47 - 1, 6.5 x 47 - 1, 223 IMP - 1, 6.5 Grendal - 1, 30x338 Win - 1
Link Posted: 6/12/2007 3:00:33 PM EDT
[#7]
Well Foob that is an interesting line up of ctg's.  9 243's and they place in the top 20.  
Link Posted: 6/12/2007 3:08:55 PM EDT
[#8]

Quoted:

The 6.5 Grendel did pretty well at the Snipers Hide Cup 2007. It beat out all but one .308 and finished 18th out of 60. Of course most of this is due to the outstanding shooter (Bruce Gordon) but it does show that the Grendel can be very competitive (it beat out 29 of the 30 .308 rifles there).

Here is the breakdown of the top 20 from a post on SH:

Top 20

1 260 Rem
2 6 mm XC
3 243 Win
4 243 Win
5 243 Win
6 243 Win
7 308 Win
8 260 A I
9 243 Win
10 243 Win
11th 243 Win
12th 260 Rem
13th 6 XC
14th 6 XC
15th 260 Rem
16th 243 Win
17th 243 Win
18th 6.5 Grendal
19th 260 Rem
20th 260 Rem



Totals

308 Win - 30, 260 - 13, 243 - 9, 6xc - 3, 6 x 47 - 1, 6.5 x 47 - 1, 223 IMP - 1, 6.5 Grendal - 1, 30x338 Win - 1


Well, from those stats, I guess it's a good thing it ain't a .308! But those 6-7mm guns seem to be kicking butt on pretty much everything! Everything in the top 20 is from 6-7mm except for that one .308, and it had more than twice the competitors as any other contestant!

I am surprised at the success of the .243, everyone of them placed top 20! Maybe we are all missing something!

Bill
Link Posted: 6/12/2007 3:26:47 PM EDT
[#9]

Quoted:
Well, NEITHER one is suitable for Full Auto and service in the US military in an M16 from what you have posted, so it doesn't matter much.

Bill


 No that's not what I said. I said its not as controllable in F/A as 5.56. I said its not suitable as a general issue service ctg. That doesn't mean that the 6.8 or the 6.5 isn't suitable as limted issue. The 30 carbine is not a general issue service rifle ctg either, but it has seen a lot of use by the US military.  The US military has used a lot of ctgs that are not a general issue service ctg. 22LR, 38 special, 7.62X39, 44 henry, 50 Spencer, 30-338, 300 mag, 6mm Lee, 45 AR, 45 S&W, 12 gauge, 30 carbine & I'm sure some others. As a matter of fact I think they are using 6.8 right now.M9
Link Posted: 6/12/2007 3:35:05 PM EDT
[#10]
I should have qualified that with the "general service issue" caveat, but I knew what you meant, and actually agree to some extent while we have 100 pound teenage girls shooting.

As a matter of fact, I think they are also using 6.5 right now. Of course it is also limited issue!

Bill
Link Posted: 6/12/2007 3:44:41 PM EDT
[#11]

Quoted:

As far as the Grendel, we've been through this before, but it essentially matches the .308 data out to 1000 yards or so, and though neither would be my choice at that distance,

Bill


Thats right the data matches. I'm not going to dispute that data, but a few people that I know are competant & were originally big fans of 6.5 say they can't match 7.62 with the 6.5. They say it's more like the 6.5 redlined, maxed out to the point it's busting bolts matchs mediocre 7.62 NATO loads. There is a disconnect between their experence & published data. M9
Link Posted: 6/12/2007 3:58:49 PM EDT
[#12]

Quoted:

Quoted:

As far as the Grendel, we've been through this before, but it essentially matches the .308 data out to 1000 yards or so, and though neither would be my choice at that distance,

Bill


Thats right the data matches. I'm not going to dispute that data, but a few people that I know are competant & were originally big fans of 6.5 say they can't match 7.62 with the 6.5. They say it's more like the 6.5 redlined, maxed out to the point it's busting bolts matchs mediocre 7.62 NATO loads. There is a disconnect between their experence & published data. M9


That's understandable, experience trumps calculations!

I don't shoot .308 except in a SOPMOD with red dot, so I can't personally compare them. I don't care to use one for long range, since when I get to that distance, I'll have to decide on using a .243 or ?

Maybe 6.5 x 47 Lapua bolt gun, since then I'd only have to buy one projectile.

Bill
Link Posted: 6/12/2007 3:59:33 PM EDT
[#13]

Quoted:
Is it a 1000 yard cartridge? Depends on if you think a .308 is. If you do, then the Grendel is essentially the same. If you don't, well it's not, but that isn't the question, so I don't want to derail this thread anymore than we have, so I'll stay out of it from here on out.

Bill


 Well a 308 with a 26" barrel is a "it'll work in a pinch 1000 yd ctg". More like a good 800 yd ctg. A 22" M14 won't reliably stay supersonic at a 1000, some will some won't. A 26" bolt gun will stay supersonic at a 1000, but its still a long way from optimal. And I'm not willing to take that data that it meets 7.62 as gospel. I'm not disputing it either, but I consider it suspect. M9
Link Posted: 6/12/2007 5:18:42 PM EDT
[#14]

Quoted:
Thats right the data matches. I'm not going to dispute that data, but a few people that I know are competant & were originally big fans of 6.5 say they can't match 7.62 with the 6.5. They say it's more like the 6.5 redlined, maxed out to the point it's busting bolts matchs mediocre 7.62 NATO loads. There is a disconnect between their experence & published data. M9


Well you must know some boobs.  

Bruce Gordon shot the 6.5 Grendel and said it did match his former .308 loads for drop and windage.  Actually, the Grendel handled the wind a bit better than the .308.

       
Link Posted: 6/12/2007 6:36:36 PM EDT
[#15]

Quoted:

Quoted:

The 6.5 Grendel did pretty well at the Snipers Hide Cup 2007. It beat out all but one .308 and finished 18th out of 60. Of course most of this is due to the outstanding shooter (Bruce Gordon) but it does show that the Grendel can be very competitive (it beat out 29 of the 30 .308 rifles there).

Here is the breakdown of the top 20 from a post on SH:

Top 20

1 260 Rem
2 6 mm XC
3 243 Win
4 243 Win
5 243 Win
6 243 Win
7 308 Win
8 260 A I
9 243 Win
10 243 Win
11th 243 Win
12th 260 Rem
13th 6 XC
14th 6 XC
15th 260 Rem
16th 243 Win
17th 243 Win
18th 6.5 Grendal
19th 260 Rem
20th 260 Rem



Totals

308 Win - 30, 260 - 13, 243 - 9, 6xc - 3, 6 x 47 - 1, 6.5 x 47 - 1, 223 IMP - 1, 6.5 Grendal - 1, 30x338 Win - 1


Well, from those stats, I guess it's a good thing it ain't a .308! But those 6-7mm guns seem to be kicking butt on pretty much everything! Everything in the top 20 is from 6-7mm except for that one .308, and it had more than twice the competitors as any other contestant!

I am surprised at the success of the .243, everyone of them placed top 20! Maybe we are all missing something!

Bill


Yes the .243 can spit bullets out dam@ fast but there are some disadvantages that come with that.  Also, all the 6XC placed in the top 15 with only 3 competing.  The single 6.5 Grendel placed in the top 20.  

I think the Grendel can do well in many competitions but really gains an advantage in competitions where recoil is a factor and primary shooting is 600 yards or less and if semi-auto gives an advantage (very big advantage when there is MPF category).

The nice part about the Grendel is its great flexibility - from being able to do such competition work to being good for medium game hunting to having decent barrel life to being a cartridge you can start you kids on - all in the AR15 platform.
Link Posted: 6/12/2007 6:39:37 PM EDT
[#16]
The other real condition accomplishment with the 6.5 Grendel is the 2005 International Silhouette Pistol Competition (Unlimited Class) where the only 6.5 Grendel competing took 1st place.  Again, the advantage was power to knock down the largest silhouettes at distance with minimal recoil while having great accuracy.
Link Posted: 6/12/2007 6:42:43 PM EDT
[#17]
Not controllable in F/A..... Seems perfectly controllable to me.

F/A 6.8
Link Posted: 6/12/2007 7:31:46 PM EDT
[#18]
Thank you, Jesse, and if the 6.5 Grendel has similar weight bullets at similar velocities (or heavier bullets but slower), then it's handling characteristics under recoil will be similar.

I can agree with the critics that the recoil of both is on the edge of what an average guy can handle. I certainly wouldn't recommend a bigger cartridge (read: bigger bullets + higher velocity = badder recoil) as a general-purpose assault rifle cartridge.

John

| 6.5 Grendel: World's Best Combat Cartridge |
Link Posted: 6/12/2007 7:37:48 PM EDT
[#19]

Quoted:
Thank you, Jesse, and if the 6.5 Grendel has similar weight bullets at similar velocities (or heavier bullets but slower), then it's handling characteristics under recoil will be similar.

I can agree with the critics that the recoil of both is on the edge of what an average guy can handle. I certainly wouldn't recommend a bigger cartridge (read: bigger bullets + higher velocity = badder recoil) as a general-purpose assault rifle cartridge.

John

| 6.5 Grendel: World's Best Combat Cartridge |


I think the average GUY can handle it, I think the average 100 pound teenage female recruit would have problems. Since those are part of the group who must qualify, then it becomes an issue.

Bill
Link Posted: 6/12/2007 7:44:38 PM EDT
[#20]
But we are also talking 3 round burst with the current M16/M4 platform.  With a 6.8 SPC or 6.5 Grendel fielding you might also consider 2 round burst as implemented by the Germans in some of their H&K systems.

Rapidly firing 2 round bursts could then be regulated by the shooter as to how much they can handle and keep on target.
Link Posted: 6/12/2007 7:50:38 PM EDT
[#21]
John,

I was trying to get on your forum to find the 6.5 Grendel POF on full auto video to post here as well.  Can't seem to get there right now....locking up IE.  Can you post that video to go along with the 6.8 vid?

Rob
Link Posted: 6/12/2007 9:23:23 PM EDT
[#22]
height=8
Quoted:
I have heard alot about the 6.5 and the 6.8 and have yet to see either one do anything serious in the matches around the country, although I did hear a marine sniper unit did well at a match out west. I suppose it's time to challange all the 6.5 and 6.8 owners to get in on the badlands tactical sniper match in september that should show if it can cut the mustard, ( better know your dope from 10 to 1000 yds though )here
Link Posted: 6/13/2007 5:59:35 AM EDT
[#23]

Quoted:
The nice part about the Grendel is its great flexibility - from being able to do such competition work to being good for medium game hunting to having decent barrel life to being a cartridge you can start you kids on - all in the AR15 platform.



 I wholeheartedly agree with that assesment. With one cavet: How does it treat that AR 15 Platform? How reliable is it going to be in that platform compared to 5.56 under adverse conditions? How controllable is it in that platform in real F/A? M9
Link Posted: 6/13/2007 6:01:22 AM EDT
[#24]

Quoted:
Not controllable in F/A..... Seems perfectly controllable to me.

F/A 6.8



 I've never said either of them absoulutely weren't controllable in F/A. I said they are less controllable than 5.56. M9
Link Posted: 6/13/2007 6:17:59 AM EDT
[#25]

Quoted:
But we are also talking 3 round burst with the current M16/M4 platform.  With a 6.8 SPC or 6.5 Grendel fielding you might also consider 2 round burst as implemented by the Germans in some of their H&K systems.

Rapidly firing 2 round bursts could then be regulated by the shooter as to how much they can handle and keep on target.



 That is correct & it would make these calibers more controllable to a novice. But from a competant rifleman's POV, 3 rd burst is an abomination that should have never happened. If you want to fire short bursts of 2 to 5 rds you do it through trigger control not through some overcomplicated gadget that totally screws your semi trigger which is the perfered firing method 90% of the time. The 3 rd burst cam continues to rotate even when the switch is set to semi. That means you have 3 different contact surfaces & 3 different trigger pulls on semi. Most novices can't tell the difference. The more experence you get the more trigger sensitive you will become. Bottom line. A M16A-1 trigger gives a much nicer more consistant semi trigger pull than a M16A-2 3rd burst abonination & its tunable, the 3 rd burst isn't.

 So while 3 rd burst works for novices, it comes with a price. You get a horrendous trigger that your experenced riflemen hate & will switch out for the older M16A-1 trigger & you sacrifice true F/A for the rare circumstance that you might want it. Its a decent set of training wheels. Some of your newer iterations of M16 & M4 have gone back to the M16A-1 trigger mechanism because of this. M9
Link Posted: 6/13/2007 9:08:07 AM EDT
[#26]

Quoted:

Quoted:
I have heard alot about the 6.5 and the 6.8 and have yet to see either one do anything serious in the matches around the country, although I did hear a marine sniper unit did well at a match out west. I suppose it's time to challange all the 6.5 and 6.8 owners to get in on the badlands tactical sniper match in september that should show if it can cut the mustard, ( better know your dope from 10 to 1000 yds though )


There's a challenge.  Have you got the details of the Badlands sniper match?  I might be up for this match....anyone else interested?


+1  Give us the details.
Link Posted: 6/13/2007 9:14:19 AM EDT
[#27]

Quoted:


Thats right the data matches. I'm not going to dispute that data, but a few people that I know are competant & were originally big fans of 6.5 say they can't match 7.62 with the 6.5. They say it's more like the 6.5 redlined, maxed out to the point it's busting bolts matchs mediocre 7.62 NATO loads. There is a disconnect between their experence & published data. M9


Give this man a prize.

I do have a 6.8 load that will perform well as far as ballistics go but to get the accuracy and load to mag length It will need my new reamer. 6.8DMC.
120grs 2650 fps. BC .438  I have shot 94 rounds within 30fps of this and no signs of pressure or bolt failure.
Link Posted: 6/13/2007 12:00:57 PM EDT
[#28]

Quoted:

Quoted:


Thats right the data matches. I'm not going to dispute that data, but a few people that I know are competant & were originally big fans of 6.5 say they can't match 7.62 with the 6.5. They say it's more like the 6.5 redlined, maxed out to the point it's busting bolts matchs mediocre 7.62 NATO loads. There is a disconnect between their experence & published data. M9


Give this man a prize.

I do have a 6.8 load that will perform well as far as ballistics go but to get the accuracy and load to mag length It will need my new reamer. 6.8DMC.
120grs 2650 fps. BC .438  I have shot 94 rounds within 30fps of this and no signs of pressure or bolt failure.



there was an article in Handloader titled "Pressure Guessing"

this should be required reading for everybody that's a handloader/reloader

it was VERY detailed, but basically, what it said was there is no reliable way for the average person to test pressure other than velocity. The pressure ring method has been the holy grail for a number of years now, but it's only marginally accurate

there's a lot of conjecture about the "old" reloading manuals and why some of the info has dropped so much. What they found out was that some of their loads had way high pressures but weren't giving any typical signs.
Link Posted: 6/13/2007 4:35:41 PM EDT
[#29]

Quoted:
it was VERY detailed, but basically, what it said was there is no reliable way for the average person to test pressure other than velocity. The pressure ring method has been the holy grail for a number of years now, but it's only marginally accurate.


 I think an Oheler PBL is pretty reliable, but you have to calibrate it with a known pressure factory load. It won't give an industry std PSI, but it will give an accurate reading of factory ammo & your handloads for comparision. I haven't read the article so I don't know if they mention the PBL or not. M9
Link Posted: 6/13/2007 4:36:16 PM EDT
[#30]
The grendel's put up a good showing at some hipower matches in longrange to 1000 take alot of 600yd matches but there is a guy showing up with a 6XC waiting for the grendels to show up.says they get his mojo going. hope to see some grendels there at badlands
Link Posted: 6/13/2007 5:08:06 PM EDT
[#31]

Quoted:
The grendel's put up a good showing at some hipower matches in longrange to 1000


 Well, I have shot a lot of 1000 yd hi-power & the 6.5 ain't got a snowball's chance in at @ 1000. There are some people trying to make it work @ 600. No real success so far though, just some broken bolts. At a 1000 its going to be shooting against the 6.5/284. M9
Link Posted: 6/14/2007 3:47:06 PM EDT
[#32]

Quoted:

Quoted:


Thats right the data matches. I'm not going to dispute that data, but a few people that I know are competant & were originally big fans of 6.5 say they can't match 7.62 with the 6.5. They say it's more like the 6.5 redlined, maxed out to the point it's busting bolts matchs mediocre 7.62 NATO loads. There is a disconnect between their experence & published data. M9


Give this man a prize.

I do have a 6.8 load that will perform well as far as ballistics go but to get the accuracy and load to mag length It will need my new reamer. 6.8DMC.
120grs 2650 fps. BC .438  I have shot 94 rounds within 30fps of this and no signs of pressure or bolt failure.


If some of the information here is right, they've been saying that these cases are reaching 65k before you see any pressure signs. I will say it again for the thousandth time reading primers isn't a good "sign" of pressure to make safe handloads. And running this way in the AR platform is irresponsible and dangerous.

I don't have any specific info that I've seen that specifically puts primer sign at 65K does anyone have that info? It would be interesting to know.


ETA: Bolt failure doesn't occur instantaneous with 1 or 200 rounds, but prolonged exposure to overpressure rounds will shorten your bolt life considerably. Each bolt is unique if you get a good one it may last several thousand rounds of high pressure loads, if you get a bad one it may only last several hundred rounds. Your gamble.
Link Posted: 6/14/2007 3:50:02 PM EDT
[#33]

Quoted:

Quoted:
The grendel's put up a good showing at some hipower matches in longrange to 1000


 Well, I have shot a lot of 1000 yd hi-power & the 6.5 ain't got a snowball's chance in at @ 1000. There are some people trying to make it work @ 600. No real success so far though, just some broken bolts. At a 1000 its going to be shooting against the 6.5/284. M9


I agree that the 6.5G is going to have very stiff competition at 1000 yards, the 6.5/284 is a heck of of rnd. I would think that the 6.5G would do well at the 0-600 yard matchs though, it will be interesting to see in the end when all the bugs are worked out of both the 6.8 and 6.5 what their final performance will be.
Link Posted: 6/14/2007 4:41:00 PM EDT
[#34]

Quoted: I would think that the 6.5G would do well at the 0-600 yard matchs though, it will be interesting to see in the end when all the bugs are worked out of both the 6.8 and 6.5 what their final performance will be.


 It should do well if it matched the data listed for it. It's not done so well so far. One thing to keep in mind though. Even if a Grendel matched the optimistic data, it would still be an underdog at 600. What people are betting on, is that the advantage of it & a semi-auto platform, will put it even at 200 yd standing slow fire &  ahead at 300 Rapid fire & maybe it won't lose so much at 600 that it will lose the match overall. I don't think thats a winning bet. But some people will bet on anything. M9
Link Posted: 6/14/2007 5:29:51 PM EDT
[#35]
Curt you mentioned the 6.5-284, that certainly is a hot rod, but just one little thing wrong with it...recoil.  Now I'll tell you one that's pretty good all the ways around, the 260 Rem.  The recoil isn't too bad on this round, about like a 243 Win, definately less then the 7mm-08.

You're absolutely right about reading primers is a bad way to judge primers. I have some mild casst bullet loads for the 7.62x39 that a CCI primer shows nothing, in fact very rounded corners, while Winchesters show flat right to the corners.  If you have a primer that is flat flat flat, like you put molten lead in the primer pocket and troweled it smooth...then you're talking pressure.  A better way is miking the head of the case and comparing it with a normal pressure fired one.  Remember ole Shotgun over on 6.5 that broke his bolt recently? He was getting the ejector hole mark on his case. That was definitely high pressure, but unfortunately he missed it before the damage was done.  On a bolt action rifle, a hard to open bolt is a sign, but we regrettably don't have that option on an AR15.

That's scarey what you said about pressure and 65K
Link Posted: 6/14/2007 5:51:53 PM EDT
[#36]

Quoted:
Curt you mentioned the 6.5-284, that certainly is a hot rod, but just one little thing wrong with it...recoil.  


 Not for LR highpower, which is what we were discussing & the reason for the ctg's existence. The most successful ctg in this game prior to the 6.5/284 was the 300 Win mag or 30-338 mag. Those two are very very simular. This is a single shot match. The reason for a 6.5/284's popularity isn't that it outshoots the 300 maggies, its that it does about as good with much LESS recoil & barrel heating. M9
Link Posted: 6/14/2007 5:55:22 PM EDT
[#37]
Joe, the 260Rem is a great performer for sure, and your right the "hotrod" is more in the recoil department.

Shotgun was getting ejector hole marks on his cases??? YIKES, I've been there before only with bolt guns. I've seen the ejector slot marks on the head of a 243 case coming out of a Ruger M77........not good!

In my personal experience with bolt guns, I've seen very few that exhibited stiff bolt opening before exhibiting primer signs, but bolt guns are a different critter altogether. You can equate some of your reloading signs over to the AR but not all by a long shot. Especially when we are all pushing the limits of the AR's capability with the 6.5 and 6.8, its great to get all that performance from the AR15 but you have to be careful with it.

As far as the primers not showing signs until 65K, that is what I've heard, I've never seen any data to back that up. I would be very interested in any info that could be had pertaining to that though.

M9, Is the factory grendel loads not reaching published data? The one that sticks out of course is the 123g Lapua running at 2650 from a 24" barrel. I hadn't heard what the accuracy of these velocities are. As far as from the 600 line, doesn't it have less wind drift  than the 5.56? I would think that the 65G would be an advantage in 2-3-6 comp. But I could be wrong, wouldn't be the first time.
Link Posted: 6/14/2007 5:55:41 PM EDT
[#38]
I have an acquaintance that's shooting 1000 yds with his 6.5-06 and he loves it.  Pretty damn much the same as the 6.5-284
Link Posted: 6/14/2007 6:07:02 PM EDT
[#39]

Quoted:

M9, Is the factory grendel loads not reaching published data? The one that sticks out of course is the 123g Lapua running at 2650 from a 24" barrel. I hadn't heard what the accuracy of these velocities are. As far as from the 600 line, doesn't it have less wind drift  than the 5.56? I would think that the 65G would be an advantage in 2-3-6 comp. But I could be wrong, wouldn't be the first time.



 It doesn't shoot against 5.56. 5.56 competes in sevice rifle category since its a US service ctg. 6.5 competes in Match Rifle since its not a service ctg. There are no limits on allowable ctgs in Match Rifle as long as the redhats assume its safe. So the sky is pretty much the limit. Its competition is the 260 & 6X47 & a myriad of other ctgs. There are limits of physics, but not of rules generally. Any oddball wildcat you can come up with can usually compete in this category. M9
Link Posted: 6/14/2007 6:09:15 PM EDT
[#40]

Quoted:
I have an acquaintance that's shooting 1000 yds with his 6.5-06 and he loves it.  Pretty damn much the same as the 6.5-284


 Yea, its been used for over 20 years. M9
Link Posted: 6/14/2007 6:14:40 PM EDT
[#41]

Quoted:

M9, Is the factory grendel loads not reaching published data?



 I don't think its velocity that is nessasarily coming up short. Its wind drift mostly. Most suspect the BCs are optimistic at least at the velocity this ctg is capable of. Thats just a guess. M9

 PS In this game ( NRA High-Power Match rifle) factory loads are irrelavant. It takes custom crafted handloads to be competitive.
Link Posted: 6/14/2007 6:21:25 PM EDT
[#42]
well think about this M9Powell, the less amount of time a bullet is in flight to the target, the less amount of time the wind has to act on it.....so bc and time and velocity all play a part in this.  Many shooters overlook time, which is velocity.
Link Posted: 6/14/2007 6:44:44 PM EDT
[#43]

Quoted:

Quoted:

Quoted:


Thats right the data matches. I'm not going to dispute that data, but a few people that I know are competant & were originally big fans of 6.5 say they can't match 7.62 with the 6.5. They say it's more like the 6.5 redlined, maxed out to the point it's busting bolts matchs mediocre 7.62 NATO loads. There is a disconnect between their experence & published data. M9


Give this man a prize.

I do have a 6.8 load that will perform well as far as ballistics go but to get the accuracy and load to mag length It will need my new reamer. 6.8DMC.
120grs 2650 fps. BC .438  I have shot 94 rounds within 30fps of this and no signs of pressure or bolt failure.


If some of the information here is right, they've been saying that these cases are reaching 65k before you see any pressure signs. I will say it again for the thousandth time reading primers isn't a good "sign" of pressure to make safe handloads. And running this way in the AR platform is irresponsible and dangerous.

I don't have any specific info that I've seen that specifically puts primer sign at 65K does anyone have that info? It would be interesting to know.


ETA: Bolt failure doesn't occur instantaneous with 1 or 200 rounds, but prolonged exposure to overpressure rounds will shorten your bolt life considerably. Each bolt is unique if you get a good one it may last several thousand rounds of high pressure loads, if you get a bad one it may only last several hundred rounds. Your gamble.


I hear you guys.  I posted on this forum, the grendel forum and 6mmBR .com.  Has anyone related primer signs to pressure. No one answered.  It seems like someone when doing pressure test would have made some notes.  I use Federal primers for sign because they will show sign first.  I load up till I see the smallest sign then back off the load .5 gr and shoot it. I work down until I get .5moa or better.  I've been doing this since 92 with the 5.56 using 69 gr sierras mostly.

Now I ve shot the 6.8 and the grendel the same way.  I've had  some stress cracks develop on a 7.62 bolt after about 200 rounds.  After reading the bolt thread I think there was too much bolt thrust with the grendel. A combination of bolt thrust and a weakened bolt because of the machining required to open up the bolt to fit the grendel.
I have not had any problems with the 6.8.  When working up loads I inspect and mic every case after every shot. I take chances but I'm careful about it.
I'm not saying everyone should do what I do. I take chances racing bullet bikes and off-road buggies. It's not for everyone. I have a dodge diesel that dynoed 482 hp.
I have it when I want it but I don't use all of it to pull a 9000lb trailer.
Sure it's hard on my drivetrain but I'll take that chance.
Link Posted: 6/14/2007 6:58:11 PM EDT
[#44]

Quoted:
well think about this M9Powell, the less amount of time a bullet is in flight to the target, the less amount of time the wind has to act on it.....so bc and time and velocity all play a part in this.  Many shooters overlook time, which is velocity.


 True enough, they all play a part. M9
Link Posted: 6/14/2007 7:01:45 PM EDT
[#45]
Constructor

Back in the early 80's I bought what is now called the preban Colt HBAR.  I noticed with factory ammo and with reloads (that I knew were well below maximum) that the primers were flatter then could be.  Then it wasn't too long ago I was on David Tubbs website reading about his bolt carrier weight and what I just described was exactly one of his selling features.  He showed a fired case, primer view, without his weight, then same load and everything with his weight.  The one without the weight had a very flat primer just like I was getting and the other one looked normal with very rounded corners.  So...I made myself one being I have a lathe and all.  Viola!!!! My primers started looking normal.  I talked to Randall about this and he said that Colt had a tendency to make their gas ports on the large side to insure that their rifles would function under all conditions.

What am I saying? Primer signs in an AR15 aren't a good  way to go.
Link Posted: 6/14/2007 7:03:10 PM EDT
[#46]

Quoted:
I hear you guys.  I posted on this forum, the grendel forum and 6mmBR .com.  Has anyone related primer signs to pressure. No one answered.  It seems like someone when doing pressure test would have made some notes.  I use Federal primers for sign because they will show sign first.  I load up till I see the smallest sign then back off the load .5 gr and shoot it. I work down until I get .5moa or better.  I've been doing this since 92 with the 5.56 using 69 gr sierras mostly.

Now I ve shot the 6.8 and the grendel the same way.  I've had  some stress cracks develop on a 7.62 bolt after about 200 rounds.  After reading the bolt thread I think there was too much bolt thrust with the grendel. A combination of bolt thrust and a weakened bolt because of the machining required to open up the bolt to fit the grendel.
I have not had any problems with the 6.8.  When working up loads I inspect and mic every case after every shot. I take chances but I'm careful about it.
I'm not saying everyone should do what I do. I take chances racing bullet bikes and off-road buggies. It's not for everyone. I have a dodge diesel that dynoed 482 hp.
I have it when I want it but I don't use all of it to pull a 9000lb trailer.
Sure it's hard on my drivetrain but I'll take that chance.



 For the above reasons I'm considering rebating the 6.5 PPC or a simular ctg to fit a 6.8 bolt. I'm not normally a big fan of rebated ctgs, but this wouldn't be a drastic rebate. I'd actually rather do it in 257" but I already have a suitable 264" barrel. M9
Link Posted: 6/14/2007 7:23:01 PM EDT
[#47]

Quoted:

Quoted:
I hear you guys.  I posted on this forum, the grendel forum and 6mmBR .com.  Has anyone related primer signs to pressure. No one answered.  It seems like someone when doing pressure test would have made some notes.  I use Federal primers for sign because they will show sign first.  I load up till I see the smallest sign then back off the load .5 gr and shoot it. I work down until I get .5moa or better.  I've been doing this since 92 with the 5.56 using 69 gr sierras mostly.

Now I ve shot the 6.8 and the grendel the same way.  I've had  some stress cracks develop on a 7.62 bolt after about 200 rounds.  After reading the bolt thread I think there was too much bolt thrust with the grendel. A combination of bolt thrust and a weakened bolt because of the machining required to open up the bolt to fit the grendel.
I have not had any problems with the 6.8.  When working up loads I inspect and mic every case after every shot. I take chances but I'm careful about it.
I'm not saying everyone should do what I do. I take chances racing bullet bikes and off-road buggies. It's not for everyone. I have a dodge diesel that dynoed 482 hp.
I have it when I want it but I don't use all of it to pull a 9000lb trailer.
Sure it's hard on my drivetrain but I'll take that chance.



 For the above reasons I'm considering rebating the 6.5 PPC or a simular ctg to fit a 6.8 bolt. I'm not normally a big fan of rebated ctgs, but this wouldn't be a drastic rebate. I'd actually rather do it in 257" but I already have a suitable 264" barrel. M9


I think that will go a long way toward reducing bolt failures.  If you don't want to turn the rims down  I hear Jamison will make custom brass with your own headstamp for $15K/5000  

After that long bolt thread Did anyone decide what the maximum loads for the 6.8 or 6.5 are?
55000 psi?  7000lbs bolt thrust? in whos barrel? With what reamer? With what twist?
At this point in the game who is to say what the maximum loads are?
Back in the 60s they thought 350hp was hot and your engine would blow if you tried to get anymore out of it. Now  they are twin turboed with nitrous and make a 1000hp.
It sure would be boring if someone hadn't  pushed the limit.

Link Posted: 6/15/2007 3:43:05 PM EDT
[#48]

Quoted:
I think that will go a long way toward reducing bolt failures.  If you don't want to turn the rims down  I hear Jamison will make custom brass with your own headstamp for $15K/5000  


    I think I'll turn some rims. M9

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