Gordon's Reloading tool is free, though unsupported since Gordon died.
It's like QL for poors. I use it all the time.
I ran this with some assumptions and allowed it to go overpressure, to about 63kpsi. I try to stay at what I think are SAAMI levels myself.
All models are incorrect. Some are useful. I think GRT is useful. If you look at the top results and filter them to focus on temp-stable powders you'll end up with H4350, RL16, RL23, N550 and N560. I suspect N555 would work just as well too. N565 looks like it would be awesome if you could stuff enough into the case. I cut this off at 106% load density. It's hard to really reach 106% without a major crrrrrrunch as you seat. I prefer to stay closer to 95-103%ish. Of course if you want to try to find it, RL26 always looks great in these models too. I cut a bunch of the slower results out to stay within the board's 10000 character limit.
Anyway, here's a great wall of GRT-generated text:
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Gordons Reloading Tool 2021.2030-NIGHTLY
Parametric powder search by generic tolerance synthesis
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File : POWDER-MEASURE-TEMPLATE.grtload
Caliber : 6 mm Creedmoor (6mm CM, 6mm Creedmoor)
Projectile : Hornady, ELD-M 24561, 0.243, 108.00 grain, 1.2559 in
Seating depth : 0.4260 in
Case : 51.70 grain H2O, 1.9201 in
Cartridge length: 2.7500 in
Initial pressure: 3626 psi
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Tolerance-Window : Target Min. Max. Unit
maximum pressure : 62000 60760 63240 psi
Muzzle velocity : 2783.3 2666.4 2900.2 ft/s
Barrel Time general (BT) : - - - ms
Bullet Lead Time 10% pmax (BLT): - - - ms
Load ratio : 106.94 75 106 %
burnt propellant : - - - %
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A T T E N T I O N - A T T E N T I O N - A T T E N T I O N
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Depending on the setting of the limiting tolerance windows, the charges can
exceed the specified maximum pressures, or have no meaningful, or even
a dangerous value. Please check a load prior to use for plausibility.
The order of the list depends on the composition of the powder list.
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propellant mass load ratio pmax v0 E0 burnt eff. BT BLT recoil
grain % psi ft/s ft-lb % % ms ms ft-lb
Hodgdon H4350 (2020-12-01) 41.99 89.8 63240 2744.3 1806 98.5 23.1 1.0031 0.9055 10.86 ATTENTION OVERPRESSURE!
Vihtavuori N565 (2021-10-22) 47.49 105.8 ▼59266 2744.6 1806 87.2 19.9 1.0462 0.9473 11.95 Working pressure close to the maximum permissible gas pressure!, Attention! Press charge! Can lead to unexpected pressure peaks!, Out of spec. tolerance
Alliant Reloder TS 15.5 (2021-09-30) 39.08 91.4 63199 2745.9 1808 100.0 24.8 1.0123 0.9071 10.25 ATTENTION OVERPRESSURE!
Alliant Reloder 22 (2021-03-29) 45.83 103.2 63238 2747.7 1810 89.8 21.6 1.0009 0.9063 11.59 ATTENTION OVERPRESSURE!
Winchester 760 (2020-09-22) 42.75 93.2 63206 2750.0 1813 98.7 23.4 0.9997 0.9041 11.06 ATTENTION OVERPRESSURE!
ReloadSwiss RS 62 (2021-04-16) 44.22 97.1 63198 2750.9 1814 96.5 23.1 1.0239 0.9181 11.35 ATTENTION OVERPRESSURE!
ADI AR 2209 (2021-03-16) 42.55 91.0 63219 2751.9 1816 97.5 22.9 0.9865 0.8966 11.02 ATTENTION OVERPRESSURE!
Hodgdon Superformance (2021-10-DEV-2) 45.88 95.2 63223 2752.1 1816 88.4 21.3 0.9878 0.8986 11.64 ATTENTION OVERPRESSURE!
Alliant Reloder 19 (2021-05-01) 45.02 101.4 63242 2756.0 1821 92.2 21.7 1.0057 0.9079 11.54 ATTENTION OVERPRESSURE!
Alliant Reloder 16 (2021-08-29) 41.84 98.4 63239 2756.0 1821 100.0 23.6 1.0176 0.9124 10.90 ATTENTION OVERPRESSURE!
Accurate LT-30 (2021-10-DEV-2) 35.41 76.5 63200 2758.4 1824 100.0 25.1 1.0070 0.8995 9.65 ATTENTION OVERPRESSURE!
Vihtavuori N550 (2021-09-27) 41.42 92.3 63229 2758.5 1824 100.0 23.3 1.0132 0.9095 10.85 ATTENTION OVERPRESSURE!
Hodgdon LeverEvolution (2021-01-28) 39.75 80.5 63217 2758.8 1825 100.0 24.0 1.0489 0.9256 10.49 ATTENTION OVERPRESSURE!
Vectan SP12 (2021-01-03) 49.60 105.9 ▼59299 2760.6 1827 90.7 20.8 1.0037 0.9207 12.47 Working pressure close to the maximum permissible gas pressure!, Attention! Press charge! Can lead to unexpected pressure peaks!, Out of spec. tolerance
Alliant 2000-MR (2021-03-01) 41.07 91.5 63202 2763.2 1831 100.0 23.9 0.9977 0.9005 10.79 ATTENTION OVERPRESSURE!
Ramshot Hunter (2021-01-07) 44.05 99.2 63233 2773.2 1844 97.0 23.0 0.9927 0.8997 11.48 ATTENTION OVERPRESSURE!
Norma MRP (2021-08-29) 46.65 102.9 63206 2779.5 1852 89.6 20.7 0.9884 0.8984 12.05 ATTENTION OVERPRESSURE!
Vihtavuori N560 (2021-09-30) 46.62 103.3 63238 2781.1 1854 89.7 21.3 1.0208 0.9167 12.07 ATTENTION OVERPRESSURE!
Alliant Reloder 23 (2020-04-08) 44.46 102.3 63109 2783.0 1857 100.0 23.0 1.0237 0.9182 11.65 ATTENTION OVERPRESSURE!
Alliant Reloder 17 (2020-02-05) 42.68 90.8 62906 2783.1 1857 100.0 22.8 0.9724 0.8875 11.28 ATTENTION OVERPRESSURE!
IMR 7828 SSC (2021-11-13) 46.37 102.2 63057 2783.2 1857 86.6 21.5 0.9883 0.8984 12.02 ATTENTION OVERPRESSURE!
ReloadSwiss RS 70 (2020-09-22) 45.93 99.2 62004 2785.0 1860 92.3 21.4 1.0236 0.9223 11.95 Working pressure close to the maximum permissible gas pressure!
Ramshot Magnum (2021-01-07) 48.51 103.2 61982 2794.9 1873 98.0 21.8 1.0280 0.9260 12.60 Working pressure close to the maximum permissible gas pressure!
ReloadSwiss RS 76 (2021-01-05) 50.50 105.8 ▼59813 2799.5 1879 95.5 20.2 1.0371 0.9399 13.09 Working pressure close to the maximum permissible gas pressure!, Attention! Press charge! Can lead to unexpected pressure peaks!, Out of spec. tolerance
ReloadSwiss RS 60 (2020-08-24) 43.12 94.1 61967 2807.8 1890 100.0 22.9 0.9738 0.8899 11.57 Working pressure close to the maximum permissible gas pressure!
Alliant Reloder 26 (2021-10-30) 47.26 100.6 61981 2828.3 1918 98.5 21.8 1.0241 0.9223 12.66 Working pressure close to the maximum permissible gas pressure!
