I shoot a lot of .223 in several bolt guns. There are a lot of AR's out there with 1 in 7 twist. My rifles are 1 in 9 so I shoot 55 grn Hornady FMJBT. A faster twist will like heavier bullets.

I shoot mixed head stamp range brass. LC is probably the best but it's tough stuff. Most of it has crimped primers also. You will need a way to swag or ream those primer pockets. I swag mine but you can cut them out also. Get a case gage and check your brass after you size it. An out of adjustment sizing die may leave your cases too large to chamber in your rifle. Been there, done that. A gage will also tell you if you need to trim your brass. I haven't trimmed any yet because it's all once or twice fired. It might stretch tho after a few more loadings, don't know.

I don't crimp.

I'm using 23.5 grns of AR Comp powder and 55 grn bullets as I previously stated. That's the load I worked up and it does everything I need it to do. I've heard that AR Comp is Alliants answer to Varget. Both are extremely versatile rifle powder.

I just use small rifle primers but some say a harder primer should be used with an AR. Don't know anything about that.

.223/5.56 is a piece of cake to reload.

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