I am wanting to build another Grendel, but not sure which barrel to go with. I had a 24" AA overwatch upper and was very pleased with the way it shot, but I want a 20" this time for hunting and medium range target shooting. I will mostly be shooting the 123grn bullets. I talked to Alexander Arms at the NRA show and they told me the barrel and bolt kits are about 8 weeks out. I also checked midway, and they are all out of stock. So I am looking for advise and input before I order one from them. Any info would be appreciated.