the beauty of an AR is that you can change uppers easily and make one firearm into many. I like the shorter barreled carbine with collapsible stock for it's lighter weight and ease of carrying, and a 300 yard shot is easy with them. I can ring a clanger at 300 non stop with mine. But, I also use the A2 with a 20" barrel a lot, and it does have more accuracy at longer range. Lastly, for varmints, I use a flat top upper with a 24" heavy match barrel and can set my scope up and easily make 800 meter shots on a standard police silhouette target, I can't begin to tell you how much fun it is to use on gophers and other varmints. I'd suggest that you look at MAPARTSINC.COM for your kit. I use their stuff exclusevly now. Their parts are fantastic, the kits are complete, and they send the upper with barrel already attached, head spaced and test fired.
have fun and shoot safe
Retired Police Officer
NRA certified police firearms instructor
Competition shooter (ret)
Avid hunter since age 9 with:
Black powder firearms
Trained at S&W, COLT and GLOCK Armorer schools
I specialize in building 1911 pistols and AR 15 rifles
And ran a gun shop for many years
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