Home Forums Hunting & Shooting AR and Tactical Rifles 7.62X39 AR-15 upper: do they work?

Thinking of this or a 300 BO.

Pros and cons of each?

My Colt AR 7.62x39 worked. Accurate with .308 bullets.

The 7.62x39 uppers work, the problem is the magazines as the 7.62x39 likes a very curved magazine and they AR's mag well doesn't lend itself to the curved magazine. This is why CMMG came out with the Mutant so you can use AK magazines.

Does the magazine issue make it worth buying a mutant?

midway has stoner mags that work with the current standard lowers.
reason i went 7.62x39 was $$$$ . much cheaper for surp 7.62
over 300bo.
of course David you can always get both!!!
and then a 458 socom....etc.

Mag issue is an issue if you intend to shoot high volume rounds and require high volume mags and perfect function...

as I recall we run a 10 or so round mag in my nephews gun.. I've not seen it make a mistake yet, but its not a 30 rounder...

300 BO uses standard .556 magazines

So does the 7.62x40 WT.

The two issues with the 7.62x39 are the bolt and magazines. The Stoner mags work well, I use the 10 round mags for hunting. I wouldn't buy a mutant because of magazines!

The bolt is another specific part, and because the diameter of the case is about as big as the AR15 can handle, it has a reputation for breaking bolts. I haven't broken mine yet, but I don't run it hard though.

The Blackout is a good compromise, but it is not quite as powerful, and not nearly as cheap as steel cased 7.62x39. It does have a better selection of factory hunting ammo. Brass can be made from .223, but it is a chore.

I built my 7.62x39 upper before the Blackout was available, I reload for it for hunting. Today I'd buy a Blackout if I reloaded, and convert ,223 brass if I felt really cheap.

Mags now are quiet a bit better than they were 8-10 years ago but some may need a little tweeking. Make sure the spring supports the follower front and rear. You can always bend the feed lips up a small amount to to make the bullet tips hit higher on the feed ramps.
Over-gassing has always been a problem. Mid gas barrels work better but an Adj gas block will help barrels that cycle too quick. If you are shooting super sonic the 7.62x39 will be 100-150fps faster than the 300 and the ammo will be cheaper.

they really pushed the 300 when it first came out, I remember that Silver fellow was all over defending the BO and trashing everything else. Now after the smoke has cleared its real mission is subsonic and when supersonic is about a 30 carbine power but twice as expensive to shoot. Definately get the AK round and not the BO.

The reason to run a 300 bo is due to the fast twist barrel which allows the use of heavy for caliber bullets and to use a supressor.

The reason to run a 7.62X39 is to burn cheap milsurp.

I always agreed... super means x39, sub means 300.221

supersonic the BO is a .30 carbine on 'roids, and conveniently uses the same bolt and mags as the 5.56. I like it, myself.

I've got a 7.62x39 AR and have had no problems using ASC short straight mags. Can't remember if they are five or ten round but they are the same length as my ten round 6.8spc mags. Makes a handy short range thumper for deer drives in the thick stuff. Shoots the surplus ammo very well.

Even in the USA there's a bunch of AK mags out there, so it would be kind of nice to have something accurate & reliable that uses them. Preferably something that doesn't cost a pile of money. May be unobtainium

I was real interested on the Rock River AR-47, but it earned poor reviews. CMMG has the Mutant of course, but they're of uncertain parentage and are not cheap.

I run 20 rd ASC mags and have a ball with my 7.62x 39
Its my favorite AR by far

Hank

Who,s x39 upper do you have?

PTR 32, I believe uses ak mags and drums. That's what I would get if it had to be fed by ak mags.

I have been very pleased with my PSA 762x39 upper and ASC 10 and 20 round mags. I have also heard about the bolts breaking, but that has not been a problem so far. Watch PSA's sales, I bought mine black Friday for $349 with free shipping. Go for it and never look back.