When comparing powders, look at max pressure loads. You obviously would build up slowly when actually reloading, but for powder comparisons, the max loads give most calculation flexibility.
Taking your figures. the max loads (for the top dozen powders) are:
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Powder type Filling/Loading Ratio Charge Charge Vel. Prop.Burnt P max P muzz B_Time
% Grains Gramm fps % psi psi ms
--------------------------------- -----------------------------------------------------------------
Norma MRP 107.9 50.8 3.29 3146 99.1 59000 10567 1.181
Vihtavuori N560 109.4 50.5 3.27 3122 96.1 59000 10627 1.182
Alliant Reloder-25 115.0 51.6 3.35 3110 99.8 57181 10207 1.192
Accurate MAGPRO 109.8 52.7 3.42 3110 94.5 59000 10622 1.186
Alliant Reloder-22 109.8 50.1 3.25 3108 98.0 59000 10317 1.186
Raufoss RA15 109.8 50.1 3.25 3108 98.0 59000 10317 1.186
Winchester WXR 112.7 50.3 3.26 3106 97.8 59000 10322 1.186
Ramshot Magnum (Big Boy) 111.4 53.8 3.49 3099 96.8 59000 10427 1.177
SNPE Vectan SP 12 111.6 53.8 3.49 3099 96.9 59000 10405 1.177
PB Clermont PCL 517 111.8 53.9 3.49 3098 96.8 59000 10416 1.177
IMR 7828 113.6 49.9 3.23 3093 96.4 59000 10242 1.178
IMR 7828 SSC 107.5 49.9 3.23 3093 96.4 59000 10242 1.178
Given the choice of those, I would knock off:
- Norma MRP - I couldn't get it
Raufoss RA15 - I couldn't get it
Ramshot Magnum - I couldn't get it
SNPE Vectan SP 12 - I couldn't get it
PB Clermont PCL 517 - I couldn't get it
Accurate MAGPRO - only 94.5% burn
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Powder type Filling/Loading Ratio Charge Charge Vel. Prop.Burnt P max P muzz B_Time
% Grains Gramm fps % psi psi ms
--------------------------------- -----------------------------------------------------------------
Vihtavuori N560 109.4 50.5 3.27 3122 96.1 59000 10627 1.182
Alliant Reloder-25 115.0 51.6 3.35 3110 99.8 57181 10207 1.192
Alliant Reloder-22 109.8 50.1 3.25 3108 98.0 59000 10317 1.186
Winchester WXR 112.7 50.3 3.26 3106 97.8 59000 10322 1.186
IMR 7828 113.6 49.9 3.23 3093 96.4 59000 10242 1.178
IMR 7828 SSC 107.5 49.9 3.23 3093 96.4 59000 10242 1.178
From those, I'd choose Alliant Reloder-25 as my first choice as it will give a full case even at lower charges and burns nearly all the powder. N560 and Alliant Reloder-25 would be a close second.
The difference in getting a full case of powder is consistency of ignition and burning - no matter if you are shooting uphill or down, the powder contact with the primer is the same. A compressed load will always be the most consistent, but to be fair, if you are above 90% fill, you should have few problems.
Kev.