So I'm gearing up to build my second AR-15. This one will be specifically for precision target shooting and the occasional varmint hunt. So weight is really not a factor.

I'm going to have a Bartlein barrel made for this build so it will be customized to my specifications. It'll have a quality high powdered scope, PRS stock, etc... I will be handloading its food.

I have a few questions about this build before I put in my order.

1. What would be the perfect length, profile, and twist? I was thinking something heavy, 20", 1/7 twist, rifle length gas system.

2. Is a custom chamber possible? I was going to ask the builder to spec the chamber to where mag length rounds won't have so much jump to reach the lands.

3. Is there such a thing as a match bolt/carrier assembly? The barrel maker was telling me to send him the bolt I want to use and he'll match it to the barrel.

4. What are some tricks I can apply to smooth things out? I plan to use Lapua brass and match bullets. I wanna try to not beat the brass up as much as a combat AR does. I've read about trimming the ejector spring and employing certain types of buffers.

That's pretty much what I'm curious about. If you have any additional information that would help this build, please post it.