5.56 to .300BLK What is the best way to do it?
- Thread starter Tikka223
- Start date
Just need a barrel to do it, Well a barrel and a shorter handguard and a gas block and tube if your going shorter since it's probably going to be a pistol length gas block over the carbine length you probably have now.
I went with an superlative adjustable gas block for my 10.5" blackout build. To be safe tho check with a Headspace gauge to make sure the barrel works with your bolt. You can do a rent thingy with true North arms where you buy the go/no go gauges then return them after and they refund you all but $20 for the rental. That's what I did for mine. I ordered a BCM forged upper and put my 556 barrel on it then use same bolt carrier group and charging handle for both so its easier to switch back and forth if I wanna shoot 556
I went with an superlative adjustable gas block for my 10.5" blackout build. To be safe tho check with a Headspace gauge to make sure the barrel works with your bolt. You can do a rent thingy with true North arms where you buy the go/no go gauges then return them after and they refund you all but $20 for the rental. That's what I did for mine. I ordered a BCM forged upper and put my 556 barrel on it then use same bolt carrier group and charging handle for both so its easier to switch back and forth if I wanna shoot 556
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So with that comes the question of component quality. For example, Radical Arms complete uppers run the 600-1000$ mark but you get a Colt IUR and you are over 1000$. I’m not super familiar with all the AR brands out there and don’t want to get something of questionable quality. A decent barrel in my DD upper was my first idea.
If you have both calibres, make sure you paint the mags for 300 blk a different colour than any mags used for 5.56, and do not mix them - it isn't necessary unless you you have both, but loading one into the other because you can't tell them apart can be.......interesting.
I guess that depends on what you mean by questionable quality. Fit and finish. Function. Accuracy?
I don't consider the AR platform as a precision instrument, and the 300 blackout even less so.
For the hassle of changing barrels every time i wanted to shoot a different caliber, i would just get an upper.
I look at the AR as lego, everything should work together unless there has been some major screw up. I've never had anything fail except from being completely shot out by many many many 1000's of rounds.
Hope you reload because this is a serious fun round! I built my upper and it’s been really good however if you plan on running subsonic ammo be sure you have a reduced power spring on standby, The only problem that I had was bolt hold open. And was quickly sorted out with the low power spring. they are available from Brownells.
