IMR 7977 & 7mm Rem Mag - School Me

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blauber

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So IMR 7977 and 162 gr ELD-X are on the way. I settled on H4831 and 162 gr SSTs, but struggled with 0.5 MOA and fliers. As a one off, I tried IMR 4350 with better results-typically 0.25 MOA at 200 yds. Both these loads achieved best accuracy at book max plus 1 grain.

Great accuracy with a stock 700 but velocity went from 2750 fps to 2780 fps with above swap..not bad but I want more. So, with the new IMR7977 and ELD-X offering I am hoping for the best I can do from my 1976 sweetheart in 7mm Rem Mag.

School me on what IMR 7977 is able to do with 154 to 168 gr class bullets compared to other powders, specific to the 7 mm Rem Mag please.
 
With the 7mm Remington Magnum and bullets from 160 - 175 grains, IMR 7828 or Norma MRP are your friends.

With the 160 Accubond or Partition in my 7 mag, I easily reach 3050 with either powder, and they shoot ragged holes at 100M

I have IMR 7977 here, but have not tried it in my M700 - 7mm Mag yet.
 
Those loads seem really watered down to me. Data shows that 7mm-08 will do just over 2700 with 162gr amax. Should be Niping at the heals of 3000fps with a 7mag
 
There is so little information out there on IMR7977 at the moment. For my situation, I'm looking for at least 100 fps more with same 0.25 MOA accuracy as with my IMR 4350 load.

I'll post IMR7977 results in 7mm Rem Mag eventually on this thread, maybe EE will beat me to it? For comparison sake, I am going to stick with the 162 SST to see if I can improve on velocity before switching over to the ELD.

Any other velocity improvements over standard fare in other calibers with IMR 7977?
 
Update: I worked up some loads with IMR 7977 in the 7mm Rem. Velocity has improved by 140 fps from 2760 fps to 2900 fps over the IMR 4350 load. This is with a stock M700 with 24" barrel. Accuracy is good too.

Hope this post may help others as there is still little information on the merit of 7977.
 
I settled at 70.1 gr with a circa mid 70's bdl. It didn't take much to find the sweet spot with 162 gr SST 15 thousands from lands. Fill volume is better..about 10 gr more than IMR4350 and 5 gr more than H4831. This rifle was slow compared to other posts but I'm happy at 2900 fps with stellar accuracy out to 500 yds.
 
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