parabarbarian
Member
A while back I asked if anyone had tried Alliant's new 300MP powder (http://smith-wessonforum.com/reloading/172692-alliant-300mp-powder-357-magnum.html). About four weeks ago one of the local suppliers had some in stock so I bought a pound to try it out. Alliant lists 18.6 gr as the maximum charge for a 158 gr GDHP which I reduced by 10% to 16.7 gr for a starting load and 17.7 as an intermediate load if the lower load did not indicate any excessive pressure.
I finally got the range to test them today.
Gun = Marlin 1894C 18.5" barrel
Bullet = Magtech 158 gr JSP
Case = Federal 357 magnum
Primer = Winchester Small Pistol
Powder = Alliant 300 MP
Ambient temperature = 90F (prox)
Results from five measurements (feet/second):
16.7 gr: average = 1675, SD = 23, Max = 1684, Min = 1635
17.7 gr: average = 1765, SD = 24, Max = 1792, Min = 1736
None of the primers or cases showed any more indication of pressure than normal for a 357 magnum. In fact the Amercan Eagle 158 gr JSP (which clocked at almost exactly 1800 fps) had much flatter primers than the 300MP reloads.
All in all I am pretty impressed with the potential of this powder in a carbine.
No accuracy reports yet. About the time I was getting ready to try some guy started banging away with a civilianized version of an M1919 and kicked up so much dust I just packed up and went home.
I finally got the range to test them today.
Gun = Marlin 1894C 18.5" barrel
Bullet = Magtech 158 gr JSP
Case = Federal 357 magnum
Primer = Winchester Small Pistol
Powder = Alliant 300 MP
Ambient temperature = 90F (prox)
Results from five measurements (feet/second):
16.7 gr: average = 1675, SD = 23, Max = 1684, Min = 1635
17.7 gr: average = 1765, SD = 24, Max = 1792, Min = 1736
None of the primers or cases showed any more indication of pressure than normal for a 357 magnum. In fact the Amercan Eagle 158 gr JSP (which clocked at almost exactly 1800 fps) had much flatter primers than the 300MP reloads.
All in all I am pretty impressed with the potential of this powder in a carbine.
No accuracy reports yet. About the time I was getting ready to try some guy started banging away with a civilianized version of an M1919 and kicked up so much dust I just packed up and went home.
