Help and Advice for an AR-47 build

[batmunch]

Hey guys, I've been looking into doing an AR-47 build. I was hoping that someone had done one and would be willing to share their experiences.

Some things regarding what I'm looking to get out of this build:

• this is just for plinking
• I want to stick with a regular AR-15 lower instead of a mutant lower/upper
• I would prefer to build rather than just buy complete uppers/lowers

A lot of people seem to shy away from this build because there can be a lot of feed issues and gas issues. I read that Bushmaster once did an AR-47 variant where they took the feed ramps and pretty much sanded out the middle part so that it was one large "U" shape. I've also read that shaving off a couple thousandth off the shoulder of the firing pin can help with light primer strikes.

Anyway, just hoping to get some advice from those who are far more experienced than I am. Thanks in advance!

 

[cop car]

Uh.. I wouldn't do anything to a firing pin. You could puncture the primer. Not good. Stronger hammer springs are sometimes needed. I would get the psa or MGI lower that takes ak47 magazines and run nothing but magpul magazines. I know that the MGI upper is wider, because the ak mag goes into the upper. I don't know how psa does theirs, but if it's a regular upper just machined, it will be VERY thin. Keep in mind that the bolt is very modified and very thin, prone to breaking lugs off the bolt.

 

[batmunch]

Uh.. I wouldn't do anything to a firing pin.

I wouldn't be doing the modifying myself. I don't trust myself enough to do that. But I do know that some companies like DPMS and Model1Sales have done modified 7.62x39 firing pins. That's more along the lines of what I was talking about.

I'll definitely take a look at the PSA and MGI lowers, but I was hoping to stick with a regular lower since I have a couple of them laying around.

 

[Trigger Time]

Here's my advice. Don't do an AR47.
it wasn't meant to be. They **** up. Buy an ar or an ak or a cmmg mutant if you must

 

[cop car]

I wouldn't be doing the modifying myself. I don't trust myself enough to do that. But I do know that some companies like DPMS and Model1Sales have done modified 7.62x39 firing pins. That's more along the lines of what I was talking about.

I'll definitely take a look at the PSA and MGI lowers, but I was hoping to stick with a regular lower since I have a couple of them laying around.

The 7.62 firing pin is different. Much bigger diameter. It's not just a modified 5.56 pin.

 

[tradertator]

Here's my advice. Don't do an AR47.
it wasn't meant to be. They **** up. Buy an ar or an ak or a cmmg mutant if you must

Bingo

 

[HamsterStyle]

When I considered this venture, I very quickly took the advice of, "if you want a 7.62 ar, build a 300aac." If you dont plan on reloading, that will take away the cheap plinking ammo pretty quickly. If you are a reloader, you can load up 300aac pretty reasonably. The feed issues are too common for me to mess with. I am a tinkerer but that really pushed me away from the platform.

 

[DapperDan]

I have one that I built a few years back, I've never personally had an issue out of the rifle itself in around the 200-300 rounds I've put through it. I know that isint a lot but it's a start I suppose. I bought a complete upper from alpha shooting sports, started with a stripped lower and added a spikes tactical lpk and also added a wolff extra power hammer spring. The one issue I had was with 1 out of the 5 mags I have had a feeding issue. I haven't looked into and just used the other ones, asc mags. Running steel cased ammo

 

[batmunch]

Dapper, thanks for your input!

And thanks to everyone else as well. I knew coming into this that the AR47 is a pretty controversial build: people either love it or they avoid it like the plague. I'm definitely going to do my research before starting anything.

 

[cop car]

Dapper, thanks for your input!

And thanks to everyone else as well. I knew coming into this that the AR47 is a pretty controversial build: people either love it or they avoid it like the plague. I'm definitely going to do my research before starting anything.

Just build one. But I wouldn't make it a gun that I'd bet my life on. It's just a fun range gun. They can be reliable if you put time and effort in it. It's not any cheaper than shooting 300blk, in fact might be more expensive, simply because brass 7.62x39 isn't that common. The mutant is probably the best buy and shoot gun. It's use of an ar10 based bolt is much stronger.

 

[DapperDan]

7.62x39 can be had for $250 shipped for 1k rounds, good luck finding 300blk for anywhere near that.

 

[cop car]

7.62x39 can be had for $250 shipped for 1k rounds, good luck finding 300blk for anywhere near that.

.. For steel cased rounds.. That aren't reloadable or subsonic.. Look up brass 7.62x39 that's able to be reloaded for subsonic...

 

[tmschuller]

.. For steel cased rounds.. That aren't reloadable or subsonic.. Look up brass 7.62x39 that's able to be reloaded for subsonic...

Why? enlighten me. I want to build one and 2 of my friends have them for just grin and cheap fun factor.. most guys are not going to a range and what I have seen or heard definitely not sub sonic. I respect your shooting desire and opinion: but for most folks they buy bulk steel case is what they shoot to paint steel, coyote hunt or put holes in paper... Thanks. tim

 

[Webster-dl]

7.62x39 AR Platform - Long Guns - TNGunOwners.com

Check out R1100R's post from 1/16/2012. There is a good picture of a bushmaster feed ramp, if you have never seen it.

My 7.62x39 AR is very accurate and fun...when it works. For me, I have gotten a lot of failure to feeds, and occasionally light primer strikes (I have the modified firing pin). Still working on it...it is something of a project gun for me.

Still, if I were to do it again, knowing what I know now, I would probably just want to get a KS-47 from PSA.

 

[cop car]

Why? enlighten me. I want to build one and 2 of my friends have them for just grin and cheap fun factor.. most guys are not going to a range and what I have seen or heard definitely not sub sonic. I respect your shooting desire and opinion: but for most folks they buy bulk steel case is what they shoot to paint steel, coyote hunt or put holes in paper...

Thanks. tim

becauee the main point of 300 blackout is that you can make it an sbr, and it still function fully. As well as how quiet it can be with subsonic ammo and a suppressor. if you want to shoot 7.62 I'd just build an ak. Folding stock and mags that work. No problems to chase. Or build a 300 blackout ar15. Ar15s that take ak mags are mainly out there for the challenge of it, and to just have it.