I've spent a ton of time going over the same dilemma, and put together a spreadsheet to compare parts. The biggest factors in the weight of the rifle will be the barrel and the optic. Since you already have a 42oz barrel, there really isn't much weight to be saved there. Based on my build, using standard Aero parts, you should be right around 9 pounds (probably less) before optics. I think that's pretty dang good for a reasonably priced 22" big boy AR! The Aero Precision handguards are already pretty light as-is. The Atlas R-One 15" is 13.79 oz with nut, and the S-One is maybe an ounce or two less. If you have the Enhanced M5 receiver, you're kind of locked in with the integrated mounting system. But I remember that being within a few ounces of the Atlas handguards anyway, so let's call it a wash for practical purposes. You can spend $50-100 to save a couple ounces on the stock, $300 to save a couple ounces on a handguard, and $250 to save 4-5 ounces on a lightweight bolt carrier. That's $600 to save MAYBE half a pound? I'd rather put that towards a scope and shoot the damn thing. Besides, at 22" this is probably a bench gun anyway. Sent from my Pixel 2 XL using Tapatalk
