Yep, I have Lyman 49th, Lee, and Nosler books, and all the handouts. I also check the websites. My Nosler book is old, so there is no Varget or Benchmark in it.
The Nosler site had max load for .223 Rem, Varget and their 55gr BT below the min the Hodgdon site had with 55gr Speer and Varget.
I have been using AA2230, and R10x for the lighter bullets. But, I wanted to try Benchmark. Then I found a bunch of Varget, and got some cannisters of that as well.
I'll start with 2.26in OAL to fit the mags. I then build up, in 5 round groups, from min to max in .5gr increments. If none of those work, I'll move to a different powder and/or change OAL.
Much thanks.