SmallCaliberCentral

I now have a 24" heavy barrel Ar that is 1in12".Any good loads in Benchmark or Tac? Tomorrow starts the search at the range,any info is greatly appreciated.I shoot a Ruger Target Grey bolt gun,but never fooled with this round in the AR platform.Thanks.

First, welcome to the .204um. Hopefully, you'll find out what you need here, for your successful answer to your questions. There's a sticky at the top of this forum that offers a lot of "favorite loads" and I know some of them feature Benchmark, and possibly TAC, too. If not, there's a wealth of loading info in the data section, at the top of the page, plus, I'm sure the AR shooters here will chime in eventually.
As always, start low and work up carefully, and no doubt something will make your rifle say "Yep, I like that one".

I've never worked with the powders you listed, but did find some pretty decent groups using X-Terminator an some great groups using Winchester 748 with CCI 450 primers and 39gr Sierra BKs. (.219" @ 100) And, I don't crimp for the AR

My only reservation about the X-Terminator is lack of verification and experimentation on seating depths due to changes in the weather. The Winchester powder, I've used quite a bit and am really confident in it.