Black rifle help!!

[checkmate19]

I am trying to figure whats worth keeping and what to pass along. I have no history on these rifles and know little about them. I have been looking on line and there are so many different makers and different uppers and so forth. The black one is 556 with a mag tactical lower MG-G4 the hand guard is Midwest industries with a palmetto barrel . the lower one is 5.45X39 with a YHM receiver . Are there a big difference in the receivers value or quality? Thanks

[Imgur](http://i.imgur.com/gREZ50x.jpg)

[checkmate19]

How about Aero Precision Inc. 762X39 X15 ?

[checkmate19]

What would you guys suggest between 762X39 or 5.45X39?

[checkmate19]

Headed to the range in a few guys. I wil be shooting the 762X39 AR , 556 AR , and a 5.7 and will see how they function. They have lots of additional goodies and I am not sure if thats always a good thing. I wonder if these are less desirable than a Colt sporter out of the box or a nice Rock River ?

[timshufflin]

I have a few different maker lowers and uppers and can't distinguish any difference in quality at all. The finish looks a little different but nothing else. On the x39 question, I have no clue but my first inclination would be 7.62 as you can find ammo easy and can hunt with it. I'm going 6.8spc.

[r-p reloader]

I've had a few black rifle calibers, my favorite is my 6.5 Grendel. It actually started life as a 6.8 spc, but after lack luster accuracy I rebarrelled. Blach Hole Weaponry is my choice of barrels. I resize 7.62x39 brass then fire form it for cheep reloading.

[musketjon]

Pass them ALL on. Don't you know black rifles are EVIL??!!??!!??!!
Jon

[canes7]

I've had a few black rifle calibers, my favorite is my 6.5 Grendel. It actually started life as a 6.8 spc, but after lack luster accuracy I rebarrelled. Blach Hole Weaponry is my choice of barrels. I resize 7.62x39 brass then fire form it for cheep reloading.

That's pretty brave. From what I've seen and read the Grendel cartridge has had a reputation for breaking bolts. Have you had this trouble?

[jbkf1003]

My new man crush is 300 AAC Blackout... Got a build planned..

[checkmate19]

I believe I will keep the Colts and 556 rifles and on the fence about the others. The X39 has been jamming but I think I found the problem. Thanks for the advice and opinions . I live pretty far from the range so its kinda tuff to do trial and error. I have so much X39 ammo that I want one to work out. Thanks