6mm x 39mm?

[Rookie]

Is there a standard reamer for the 7.62x39mm necked down to 6mm with a 20 degree shoulder? What name does it go by? I have 2500 Lapua 7.62x39 brass and an AR15 6mm barrel blank.

 

[DCRYDER]

Not my area of expertise, but we seem to be the only two online right now. My inexperienced opinion?

Sounds like a 6mm/220 russian.

Problem is boltface size. 223 boltface needs to be opened for 7.62 or ppc boltface.

My inexperienced advice: sell or trade 7.62 brass for Lapua 223 brass and do a 6x45mm (223 necked up to .243)......

OR

Go on to a 6PPC....I've heard they shoot pretty good.

Hopefully some more EXPERIENCED people will chime in.

 

[Rookie]

Not my area of expertise, but we seem to be the only two online right now. My inexperienced opinion?

Sounds like a 6mm/220 russian.

Problem is boltface size. 223 boltface needs to be opened for 7.62 or ppc boltface.

My inexperienced advice: sell or trade 7.62 brass for Lapua 223 brass and do a 6x45mm (223 necked up to .243)......

OR

Go on to a 6PPC....I've heard they shoot pretty good.

Hopefully some more EXPERIENCED people will chime in.

Should have stated that the AR15 I have is already chambered for 7.62x39 so the bolt face is not an issue.
Are the 220 russian and 7.62x39 the same length?
Thought about a 6ppc but I want a 20 degree shoulder angle for easier feeding from the magazine.

 

[DCRYDER]

Again I am no expert on this because I have never necked 7.62 to 6mm, I know this is a long way to go and needs to be done in more than one pass.

But if it were me I would do a 6ppc no turn chamber since it is a semi-auto. If I'm not mistaken about all of White Oak Armory's cartidges have a 30* shoulder and they say that they cycle just fine. One pass with 220 russian Lapua brass with a 6mm expander and bang away.

Hopefully someone with more first hand experience will chime in.

 

[Laurie]

Sorry, not more experienced in this matter, but I do remember there being a chapter in Glen Zediker's original AR15 book 'The Competitive AR15' in running one as a poor man's 6PPC using IMI 7.62X39mm brass as the starting point.

http://www.zediker.com/books/ar15/ar15main.html

Zediker says, or maybe I read it elsewhere, that the AR15 bolt-head design at its dimensional limits with this larger diameter case-head and lug cracking usually appears after a few thousand rounds, sometimes not so many in fact, and requires regular and careful checks on bolt condition.

He writes that the results were good, but using this brass and cartridge even in no-turn form involved a great deal of work as it's not a simple neck-down and use. Whether there is a plain wildcat necked-down 7.62X39 form, and if so whether that creates its own problems is beyond my ken. If there is, you would wonder why he didn't use that rather than go the PPC route.

 

[Eddie Harren]

6mm Beggs?

 

[CJ6]

What DocEd said +1

 

[DHD]

Is there a standard reamer for the 7.62x39mm necked down to 6mm with a 20 degree shoulder? What name does it go by? I have 2500 Lapua 7.62x39 brass and an AR15 6mm barrel blank.

Go here (6mmAR) and read that (6mmAR).

 

[jonbearman]

I would post on ar15.com,they will likely have the answer. I would call dave kiff at ptg and ask him If he has ever made a reamer.By the way it sounds like a neat idea.

 

[Kenny474]

Maybe see if you can contact Gene Beggs? He is supposed to sell 6mm Beggs reamers and dies, and I believe, not positive by any means, it is possibly the same or very similar to what you are proposing.

Little more info on it: http://bulletin.accurateshooter.com/2008/05/beggs-develops-radical-rig-in-west-texas-tunnel/

His E-Mail is at the bottom.

On a side note, his skeleton rifles are awesome. Very simple in design, but very accurate.

 

[Rookie]

Is there a standard reamer for the 7.62x39mm necked down to 6mm with a 20 degree shoulder? What name does it go by? I have 2500 Lapua 7.62x39 brass and an AR15 6mm barrel blank.

Go here (6mmAR) and read that (6mmAR).

Thanks! That's just what I wanted.
http://www.6mmbr.com/gunweek068.html

 

[DHD]

Yeah, me too. I plan to order one in January. I already have a Grendel so brass ain't an issue.