300BlkTalk

Well, on a whim, and after getting some really good prices on parts. I built a 7.62x39 AR15. I have built numerous AK47s over the years. I had always avoided the 7.62x39 AR15 because of magazine feed issues and bolt breaking issues. But things have improved a lot in both of those areas. I am going to get a increased power hammer spring for the steel cased 7.62x39. I have mostly fired brassed case reloads thru it, but did fire 20 rounds of wolf and did have 2 fail to fire. I believe this is a known problem using standard hammer spring, because of the nature of the berden primers.

You might also look at getting an enhanced firing pin.

That took care of the issues I had with Russian ammo.

I think this is in my near future. It just makes sense to me to have a firearm that can shoot 7.62x39. I have an SKS but a modern rifle would be a better choice. I sometimes think it would have been a good idea to build a grendel in 264LBC since they use the same bolt as the AR-47.

It seems like when everyone went to the 9310 steel the broken bolt thing became a thing of the past for both the AR-47 and the 6.5 Grendel

Nothing wrong with a steel case range blaster for the kids if nothing else.

Anyone have a suggestion for a barrel with good feed ramps ?

TTF

I was inspired to make one a while back, I remembered shooting one of the old Colt 7.62x39 rifles during the "ban" years. They were awesome.

Mine has a cheap clearance sale barrel. It's always functioned great, very accurate and fun to shoot suppressed. The only drawback to them are the magazines. Good ones aren't cheap, and cheap ones aren't good....

I got my barrel from BCA. I wanted one with a .311 grove diameter so I could shoot .311 or .308 bullets.

brutis wrote: ↑Mon Sep 23, 2019 7:14 pm I got my barrel from BCA. I wanted one with a .311 grove diameter so I could shoot .311 or .308 bullets.

I looked at their barrels, description didn't specify .308 or .311. Just curious where did you find that info?

TreeTopFlier wrote: ↑Fri Sep 27, 2019 9:35 pm

brutis wrote: ↑Mon Sep 23, 2019 7:14 pm I got my barrel from BCA. I wanted one with a .311 grove diameter so I could shoot .311 or .308 bullets.

I looked at their barrels, description didn't specify .308 or .311. Just curious where did you find that info?

I must have been suffering from a very bad case of brain fartyness the day I posted that.

I actually got it from Anderson Mfg. Saw the grove diameter in the reviews, an Anderson rep responded to someone when they asked what the grove diameter was.

I just went to their site but can't find the barrel I got or any reviews for the ones they have now.

You could contact BCA or Anderson to find out for sure.

Thanks,
I have casually wondered how barrel manufacturers approached this. .308 so you can use standard bullets or .310 so you can shoot cheep steel cased metric ammo. I suspect they make sure they are compatible with the most common ammo.

If you don’t have an enhanced firing pin, that’s a must for an AR in 7.62x39. And will usually eliminate any light strike issues with imported steel ammo. I think they’re like $8 from places like PSA. I’ve not had an issue using a std. single stage fire control group and std. weight hammer spring with Commercial or surplus 7.62x39.

If you still have issues with primer strikes, a stronger hammer spring is the next cheapest option. But on a single stage GI trigger, something like a Wolff xtra power spring will touch off everything but give you a 10lb pull.

I have a 5.45x39 upper and it only runs reliably with an enhanced pin and xtra power spring. But I hated the heavy pull so I swapped in a RRA NM 2 stage trigger from another lower and kept the Wolff xtra power spring and that was reliable and still gave me a super light trigger pull, since you’re not overcoming the hammer spring to fire.

If you’re looking for a good cheap 2 stage trigger, and the RRA is too pricey, check out the Larue MBT-2S for under $90.