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mblat
01-08-2006, 12:50 PM
Which one of the AR conversions to choose?
6.8 seems to be much more powerfull carthride, but it is still in question if it will ever take off.
7.62x39 is cheap ammo, available everywhere, but it's BC is crap and bullet is outdated...

Stanze
01-08-2006, 12:53 PM
Buy a SKS, get your 7.62x39mm jollies, then buy the 6.8mm SPC and be cutting edge futuristic. Barrett is embracing it, that's reassuring.

http://www.barrettrifles.com/rifles.htm

pidooma
01-08-2006, 1:13 PM
I've heard that the 7.62x39mm conversion can be a little finicky due to the AR magazine well design, which doesn't allow for the taper associated with AK mags/ammo.

Based on that, I'd probably choose to go with the 6.8 SPC instead as there seems to be more development happening in that arena than the 7.62x39mm AR arena.

delloro
01-08-2006, 1:50 PM
why do you want something besides 5.56? let your objective make your choice. just remember that nothin' will be as cheap as 5.56 or M43 to shoot.

MicronuT
01-08-2006, 3:15 PM
i also have heard nothing but bad experience with the 762 calibers.. id probably try the 6.8's and see how that works

atek3
01-08-2006, 3:53 PM
If you want an AR conversion with CQB viability but also good retained energy and wind drift beyond 500 yards consider the 6.5 grendel (http://www.65grendel.com/forum/). It isn't as 'tacti-cool' as 6.8 SPC, but ammo for the 6.5 grendel is readily available now, also Wolf's "Wolf Performance Ammo" division is coming out with two loads, a 123 gr softpoint for hunting, and a 120 gr OTM for tactical uses. Also after a long run of problems, the 6.5 grendel has reliable high caps, which I suppose is an irrelevant concern living in the PRK.

atek3

mblat
01-08-2006, 4:02 PM
If you want an AR conversion with CQB viability but also good retained energy and wind drift beyond 500 yards consider the 6.5 grendel (http://www.65grendel.com/forum/). It isn't as 'tacti-cool' as 6.8 SPC, but ammo for the 6.5 grendel is readily available now, also Wolf's "Wolf Performance Ammo" division is coming out with two loads, a 123 gr softpoint for hunting, and a 120 gr OTM for tactical uses. Also after a long run of problems, the 6.5 grendel has reliable high caps, which I suppose is an irrelevant concern living in the PRK.

atek3


I thought about Grendel. My main objection to it is that it is single source equipment. You have to buy everything from Alex. Arms, while 6.8 uppers avalable from varaety of sources.

metalhead357
01-08-2006, 4:04 PM
oK, SO NOW YOU GOT ME CURIOUS!

sO what else IS AVAILABLE THEN as an upper besides the 6.8, 5.56, and x39????????????????
Would be nice to have a choice.... I know I've seen the .22 uppers:rolleyes: but what else is there?? 5.45???????

Am I correct in assuming that .308 is just simply too large for the standard AR frame????????

TonyM
01-08-2006, 4:12 PM
The overall length of .308 is too long for the magwell.

Other than the ones listed in this thread already I've seen .45, 9mm, .40S&W and 50 Beowulf.

ETA:

Oh yeah, Rhineland is planning to release a 5.7x28 upper for ARs, but that will be a challenge for us, right now it looks like there are only 50 round mags for it.

http://www.rhinelandarms.com/57/pics/57proto3.jpg

bu-bye
01-08-2006, 4:20 PM
oK, SO NOW YOU GOT ME CURIOUS!

sO what else IS AVAILABLE THEN as an upper besides the 6.8, 5.56, and x39????????????????
Would be nice to have a choice.... I know I've seen the .22 uppers:rolleyes: but what else is there?? 5.45???????

Am I correct in assuming that .308 is just simply too large for the standard AR frame????????

Yeah 308 is to long. 50 cal Beowulf seems to be the hardest hitting thing around but drops like a brick past 200 yards. I'm sure it makes a great urban tac gun. Had the chance to shoot one and it felt nice. Anything you hit with that bad boy IS GOING DOWN!!!! Think of it as a shotgun slug. There is also the 460 Socom which I have been looking at as it takes USGI 30rd mags which I have.

delloro
01-08-2006, 4:54 PM
oK, SO NOW YOU GOT ME CURIOUS!

sO what else IS AVAILABLE THEN as an upper besides the 6.8, 5.56, and x39????????????????
Would be nice to have a choice.... I know I've seen the .22 uppers:rolleyes: but what else is there?? 5.45???????

Am I correct in assuming that .308 is just simply too large for the standard AR frame????????

yes, the 5.45 is called the 21 genghis. you can also get 22 and 6mm PPC, some will do the 22, 6 and 7mmBRs, (KKF in Fl IIRC), there's more, but it's all either bux or a PITA.

atek3
01-08-2006, 5:03 PM
Jury's still out on 6.5 Grendel through a 14.5"-16" bbl.

What do you mean, terminal effectiveness from a short barrel?

pidooma
01-08-2006, 5:38 PM
Here's something for those folks that want something with a little more power to it than the .458 SOCOM or .50 Beowulf in an AR-15 platform: The .500 Phantom (from the guys that brought you the .458 SOCOM). Looks like they're actually doing a limited group buy on it.

A picture of the .500 Phantom rounds next to some .458 SOCOM rounds:
http://img.photobucket.com/albums/v617/martytw/DasPhantom.jpg

Some threads:

http://www.ar15.com/forums/topic.html?b=3&f=121&t=255883


http://www.ar15.com/forums/topic.html?b=7&f=121&t=319770

mblat
01-08-2006, 5:53 PM
Here's something for those folks that want something with a little more power to it than the .458 SOCOM or .50 Beowulf in an AR-15 platform: The .500 Phantom (from the guys that brought you the .458 SOCOM). Looks like they're actually doing a limited group buy on it.

A picture of the .500 Phantom rounds next to some .458 SOCOM rounds:
http://img.photobucket.com/albums/v617/martytw/DasPhantom.jpg

Some threads:

http://www.ar15.com/forums/topic.html?b=3&f=121&t=255883


http://www.ar15.com/forums/topic.html?b=7&f=121&t=319770


More power than .458 SOCOM?? Well... Hmm.... I don't really see myself trying to shot down helicopters.:)
I am looking to something more practical. 6.8 would fit it purfectly, but uncertainty with very future of this platform makes me uneasy.

atek3
01-09-2006, 5:17 AM
Then there is the lack of US made 6.5mm bullets that have good performance in gelatin testing. Dr Roberts was telling me that there is military requirement to use US made projectiles. Therefore, testing of foreign projectiles is not included in official tests because the bullets could never be selected to use.


I smell BS to me. The fact is, they didn't say, lets find the most effective bullet, then design a cartridge around it. They started with a case in mind, the 30 remington, then found the most effective bullet from that case. The 43 mm case was so long that the most effective bullets that could be within magazine length were 270. A case that long can only fit stubby bullets like the .264 hornady V-max (not a great performer in man) or the 115 gr hornady .277 OTM. I'm curious to see whether the SPC team tried the hornady 129 gr SST or any of the mid weight nosler or sierra offerings.


When Chris Murray (one of the 6.8 SPC designers) was looking at different caliber options, they first thought the SPC would be a 6.5 or 7mm, but they ended up with slightly better accuracy from the 270's so now we have the 6.8 SPC...


Quick someone call the thousand yard benchrest community, apparently they've been shooting the wrong caliber.

atek3

atek3
01-09-2006, 8:00 AM
roger... argument over.

atek3

BigAL
01-09-2006, 8:43 AM
While I am interested in chambering the AR in something in between 5.56x45 and 7.62x51 the long term availability of these cartridges has me a bit leery to drop my money into them. I'm not so much interested in the inherent long range accuracy of these rounds as I am an advantage in terminal ballistics over 5.56. Until something gets standardized on or gains widespread popularity i'll just stick to shooting and stockpiling the heavy OTM .223 rounds.

mblat
01-09-2006, 9:59 AM
Contrary to popular belief 6.8 SPC never was meant to be an across the board replacement for 5.56 or 7.62.


That is intresting..... What is it for then? I can't see that Remington says:
"Let's develop new load that we are going to sell only to SpecOps."
Where is the profit in this?

lostark374
01-09-2006, 10:20 AM
id like to see and upper in .223 wsm i think that would be cool