Re: Whats a 5.56/.223 limits out of a 18"
<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Rprecision</div><div class="ubbcode-body">Thanks for all the replies,
I think I need to revist what I got when the temps warm up
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First, what loads are you using? Most people I know handloading a .223/5.56 for a gas gun don't get the loads up to snuff for a 77gr. bullet to stabilize. The 68/69/70's should all stabilize. Most loads I see for sale are loaded to .223 pressures.
IMO, if you are going to push these hard with a 77 gr. bullet, you need a 5.56 chamber or at least a Wylde chamber. In most cases the .223 chamber won't allow enough pressure before popping primers to get the 77's to work.
If you do change barrels, all you need to do is go to a 1-8" twist. That will stabilize the heaviest bullet you can run through an AR15 magazine. If you want to go heavier then go to a 1-7" twist. But, count on single feeding them.
Anyways, as you noted the keyholing means the bullets aren't stabilizing. With a 1-9" twist, I'm thinking it's because they aren't pushed hard enough. Change the speed factor first if you can. If not go to the 1-8" twist barrel.
You can at that point, make up whatever excuse you want to, to go as expensive as you want to. But, any of the standard names will serve you just fine.