Well I thought I had settled on a bear load for my 300RUM but I recently changed the stock so I figured I better do some checking.
My old load was
200 AB OAL just clears mag
GM215M
94.0 Retumbo 3050fps
Av. Velocity for 10 shots today was 3125. I don't really believe it though because I used my same drop chart as before set to 3050 and was on at 100, 500 (7.5), and 820 (17).
Today I also tried:
200 AB OAL just clears mag(lots off)
GM215M
91.0 RL25
Av Vel for 10 shots today was 3129. Once again same thing, original drop chart works fine.
Nearly the same 5 shot groupings at 100 yd 3/4 to an inch but at 500 the difference started to show.
94 Retumbo did a 6 high 10 wide 5 shot group at 500. 91 RL25 did 1 3/4 x 7. I was grinning for sure.
94 Retumbo then did a 12 high by 15 wide 5 shot at 820.
RL25 load 8x11.(Didn't get as lucky as the 500 yd) But it definately has turned my attention over to the RL25 for playing a bit more.
Had a 10 shot 39 ES for the Retumbo, 28 ES for the RL25 but here again I don't have much faith in the Chrony numbers. I do however have faith in vertical bullet holes.
Another load that mine likes at 100yd is 100gr Retumbo, same primer and a 180 Btip. 3312 AV vel. Cuts holes but I have learned that don't mean much. Will have to see what she does when I stretch her legs.
Good Luck Tommy,
HPA