Thoughts on IMR 7977?

[rtraverdavis]

Does anyone use IMR 7977 for a 7mm Rem Mag? I'm looking to load 160 grain Accubonds. I've fooled around with this powder a bit with 140 grain bullets, but none of the variations grouped, and I ended up finding a sweet load for the 140s with 4350, so I quit messing with it. I'm thinking the 7977 might do better with the heavier bullet, I'm curious if anyone has some words of wisdom to add.

 

[Corax]

I can't help you with the 7977, although I am curious as to how it turns out. I also shoot a 7 mag. I have been using H-4831 for 140 gr copper bullets, and mostly shooting my stash of factory ammo with the 160 gr Accubonds. 4 boxes takes a while to go through. Based on the penetration with the copper bullets, I have tended to use them for everything from antelope to elk. I know they do not retain energy at long range as well as the 160s.

Back when everything was un-obtainable, I wound up with a collection of different powders. I am trying to standardize, and seem to be settling on H-4831 and Varget.

Good luck.

 

[belly-deep]

I've only tried 7977 with 140's. I got decent accuracy but velocity was a little low.

When in doubt I always turn to RL22 in a 7 mag. The new RL26 is on my list to try though.

 

[rtraverdavis]

Thanks guys. I've got a jug of RL22 that I'm going to start messing with soon as well. Headed to the range this weekend, I'll let you know how the 7977 goes.

 

[N2TRKYS]

RL26 gives me more velocity than RL22 in my 7 SAUM. I'm getting 2950 fps(could get more but stopped there) with 160 grain Accubonds in a 22" factory barrel.

 

[sn.outdoors]

I can't speak for 140's, but with heavier bullets 7977 is the most consistent powder in both of my 7RM's. It is not the fastest powder, but I'm getting single digit SD's and 1/2 moa or better out of my factory rifles. I've shot it with 160 accubonds, 168 berger classic hunters, and 160 SGK's, and 180vld's and I was able to find an awesome load with each of them pretty easily. The Classic Hunters were the easiest to dial in.

 

[rtraverdavis]

After trying a few different variations at the range this weekend, the best group I got was about 1" at 100 yards with 68.5 grains of the 7977. I'm going to keep working on it, and try some RL22 loads until I can get under that 1" mark with 160 grain Accubonds. Anyone have a RL22 pet load for a 7mag?