[fabsroman]

Okay, I think I made up my mind. I am going to get the AR-10(T) Ultra from Armalite which uses the .300 RSAUM cartridge because I think I can get it for around $2,000. Trying to find AR-10 lowers and custom uppers is pretty tough, but I did happen to find some uppers from Accuracy Systems for $1,600 in .270 WSM, 7mm WSM, and .300 WSM. Actually, I just found those uppers a couple of minutes ago, and am now debating whether or not to buy one of those uppers and a $400 lower, or to buy the entire Armalite AR-10(T) Ultra. Buying a complete gun from Accuracty Systems will cost me $2,200 or more.

Along with the AR-10, I am going to get a Rock River AR-15 lower from adcofirearms.com. Then, I am going to get a custom upper in .25 WSSM from Dedicated Technology. I really like what I saw on the limited website for Dedicated Technology. He uses Oly barrels and he provides the WSSM magnums in .25, .243 and .223. I figure I can buy a couple more uppers for the AR-15 as time goes by (i.e., I can afford the uppers and additional scopes).

How hard is it to change uppers on an AR-15, and does it affect the scope's zero on them? The latter is the more important question of the two.

Last but not least, does anybody use the picattiny rail on the gas block for anything. I wouldn't mind mounting a laser sight on the AR-15, but it looks as though mounting it on the gas block would get in the way of the scope.