I got excellent accuracy with IMR4350 in my 270wsm with 150g bullets and also with my son's 6.5 cm and 140g bullets. RL26 gave about the same accuracy with more velocity in both.
I'm good as well with my 24" regular 280 Rem.
2950 fps-160g PT over RL26
3045 fps-150g AB blems over RL26
3100+fps- 140g Hammers over IMR4350
All with excellent accuracy.
Welcome to the forum! My adult son is shooting 120g Ballistic tips in his 6.5 cm, he shot a 3/8" group at 200y, I wouldn't have believed it if I hadn't been watching through my spotting scope. He then shot a nice Arizona mule deer buck last month, DRT.
I started my son with a 243 Win 23 years ago, he practiced a lot, then shot several deer, most were bang flop using 95g and 100g various bullets. Then we were required to use lead-free bullets, the first time was a Barnes TSX, he heart shot the buck luckily as the bullet just penciled through...
If you are not happy with the results of those 2 bullets try the regular 180g Accubonds, my M70 300wsm shoots them into bughole groups.
Wow, that muley buck in your avatar is a dandy! What state did he come from?
I have the exact same rifle and love it! I have worked up a good load with the 70g RDF's over CFE223 that average about 3250 fps, but I have only shot paper. We have to use lead-free bullets here, so I'm using 63g Hammers for coyotes and 50g BTLF for ground squirrels, both have the same point...
I sent Alliant an email and ask, here is their reply.
It is still being made and by no means discontinued.
Currently the bulk of the issue with powder (all powder companies) is the Lack of Nitrocellulose. Nitrocellulose is a key component in double base powders. All our powders are double...