7.62x39ARI... Stanag mag compatible

[JGSFAB]

For years now I've been trying to come up with something that fits standard (ish) AR15 magazines (or some variant), takes LRP and 308 dia bullets (I've been blessed with loads of both). Easy to form would be good as well. The 30ARX comes really close being a necked up grendel (I feel like the 442 rim is a good compromise of strength an size).
But then my weird brain asked - what if we make a 7.62x39imp that blows the body out to Stanag mag taper? Give it a 30deg shoulder to still feed but slow the brass flow... 308x39ARImp?
.311 will shoot from a .308 bore so brass 7.62x39 would fireform convert. Necked up grendel dies? Have not whittled out my own dies but why not a Die/resize reamer to go along with my custom finish reamer. A 300Blk barrel would a good victim, I shoot 300Blk and its fine just 7.62x39 def has more sauce.

Comments>? Does it just seem like I want a project?

Read More

 

[Nosferatu]

Not a horrible idea, but not one I'd suspect would catch on either.

I'd personally rather see the 6mm Wolverine catch on or a version of the 6mm ARC that uses STANAG mags.

 

[JGSFAB]

Not a horrible idea, but not one I'd suspect would catch on either.

I'd personally rather see the 6mm Wolverine catch on or a version of the 6mm ARC that uses STANAG mags.

Not really concerned with marketing, kind of the opposite.
The 30 ARX really is a good idea, simple neck up. But this ARi would be more capacity and thats kind of the name of the game as far as 30cal AR15s I guess.
Closer to that 308w thump in a small package.

 

[JGSFAB]

So the Grendel reamer I had instock had some issues, 1-carbide , pricey for my junk project. 2 - oil grooved bushing pilot, the plan was to use a oil groove pilot on a std journal so I could have a 30cal pilot on a 6.5mm reamer.
So in chats somebody brings up the PPCs. Same shoulder diameter, same shoulder angle... and I have some 6.5mm ones so old they're in old stock. Also have an old 30cal neck and throater lol. Let's go Mutt special!
Went to Bimart and grabbed some brass boxer primed 7.62x39 , $8.29 / 15 on sale lol.
I have a random 300blk barrel in the white , no gas port... looks like a good fire form barrel to me.

 

[JGSFAB]

Had loads of fun deepening the neck then sending the oversized bushing 6.5PPC reamer to 7.62x39 junction... Then finding I didn't send the neck reamer deep enough... so swap, check swap check etc. Finally got to a barrel that could chamber 7.62x39.
Fireforming is fun stuff, had SMACK the charging handle (might have been better if I had a gas tube lol).

Its really just temp barrel to get some samples. No Pressure signs , didn't really get enough pressure to square the shoulders either.
They felt plenty hot tho prob just the bolt action ar lol.

 

[JGSFAB]

Made my first sizing die... some success. Will make a better one with the real resize die reamer instead of a 6mm PPC resizer then punched out to 0.328. Oh well got my sample round to check my reamer print against.

 

[DirectDrive]

What about a SOCOM case necked down to .308 ?
It would single-stack in a USGI mag.

Here's a 375 SOCOM

 

[JGSFAB]

What about a SOCOM case necked down to .308 ?
It would single-stack in a USGI mag.

Here's a 375 SOCOM
View attachment 1479698
View attachment 1479699

It comes down to bolt if you want speed, more capacity won't do much good if the bolt won't take the pressure. They don't double stack either.
Also pretty sweet shooting std 7.62x39 to make your brass. Neck forming is tedious.

 

[Stomper]

You should stop wasting so much of your time and watch more TV!

 

[JGSFAB]

You should stop wasting so much of your time and watch more TV!

I guess this is what happens then there's a writers strike and the old TV is just old.

I've been searching for the most powerful/ double stackable 30cal AR15 cart for a while.
First attempts where like a 30 sabercat/rem 30AR/etc. But the .473 doesn't stack in a Stanag mag without lots of issues.
It sucks shortening the 308w that much anyhow.

 

[JGSFAB]

Hmmm....

 

[JGSFAB]

Well reamers and gauges are done, popped the extension off a 300blk barrel so I'm ready to make chips I suppose.

 

[JGSFAB]

It locks, it loads, the GO goes, the NOGO does NOT.
Stacks in the mag great, manually feeds no issue.

 

[JGSFAB]

Well it's finally time to resize the fire formed 7.62x39 which in the proper mag fed and shot just fine. 7.62x39 is so low pressure it didn't care about the 308 size BO barrel.
Good plinking rounds lol.
Decided on IMR4227 because I had it and quickload gave the best velocity and best fill %. 99.7 burnt as well.
18gn 1667fps - 19gn 1774fps - 21gn 1987gn
Had 1 hot one that hit 2025fps, thinking it had an 1/2 grain. No pressure signs at all , next is 21.8gn which should give 2050fps.
165 Nosler BTSP 30-06 bullets that I have bins of.
A very satisfying recoil impulse and low gas blow back with the banish46 (just received last week, signed/ordered at SHOT ).
The package seems to work, buy brass case 7.62 have fun plinking with it then reload.