BiknSwans
Member
I’ve been getting higher than expected speeds using BE-86. I’m using an M&P Pro, which has a 5 inch barrel and using a Caldwell chrono. For my latest load, I wanted to go to a reasonably high power factor. I want to use these rounds as a practice round that approaches major (165 power factor), but safely. I have been shooting .40 S&W at USPSA matches, in Limited Major, but it will be less expensive to shoot 9mm in practice. And I’m not good enough to worry too much about shooting exactly the same round in practice and matches.
For the 124 grain Acme, OAL 1.125 I got the following:
grains speed PF
4.5 1047 130
4.7 1100 136
4.9 1142 142
5.1 1173 145
Load data at Alliant’s website for 125 gr lead RN, 1.120” OAL, 4 inch test barrel, 5.7 grains BE-86 yields 1,179 fps. Power factor is 146. This data most closely matches my load.
I’m getting about the same power factor at 5.1 grains as Alliant does at 5.7. I think I’ll stop at 5.1 for now. I don’t feel comfortable exceeding the maximum power factor that Alliant data indicates.
I reviewed all the 9mm data for BE-86 at Alliant’s website, and the maximum power factor for 8 different bullets ranged from 140 to 150.
I have been loading for about 5 years now, and have always gotten speeds that were about what I expected. I have checked my electronic powder scale (Frankford Arsenal) against a beam scale and a friend's more expensive electronic one and they were in agreement. I’ve also checked my chrono, a Caldwell, against the same friend's LabRadar, and they agreed. I also got higher than expected speeds loading Precision 147s and Acme 145s in earlier testing. In fact, I got a power factor of 156 using the Acme 145s over 4.5 grains of BE-86.
Have any of you noticed a higher than expected velocity using BE-86?
Can a one inch longer barrel make that much difference?
My only theory right now is that BE-86 is slower than some of the other powders I’ve used and is still at a decent pressure when the bullet is in the last inch of the barrel, giving the bullet an additional speed boost.
For the 124 grain Acme, OAL 1.125 I got the following:
grains speed PF
4.5 1047 130
4.7 1100 136
4.9 1142 142
5.1 1173 145
Load data at Alliant’s website for 125 gr lead RN, 1.120” OAL, 4 inch test barrel, 5.7 grains BE-86 yields 1,179 fps. Power factor is 146. This data most closely matches my load.
I’m getting about the same power factor at 5.1 grains as Alliant does at 5.7. I think I’ll stop at 5.1 for now. I don’t feel comfortable exceeding the maximum power factor that Alliant data indicates.
I reviewed all the 9mm data for BE-86 at Alliant’s website, and the maximum power factor for 8 different bullets ranged from 140 to 150.
I have been loading for about 5 years now, and have always gotten speeds that were about what I expected. I have checked my electronic powder scale (Frankford Arsenal) against a beam scale and a friend's more expensive electronic one and they were in agreement. I’ve also checked my chrono, a Caldwell, against the same friend's LabRadar, and they agreed. I also got higher than expected speeds loading Precision 147s and Acme 145s in earlier testing. In fact, I got a power factor of 156 using the Acme 145s over 4.5 grains of BE-86.
Have any of you noticed a higher than expected velocity using BE-86?
Can a one inch longer barrel make that much difference?
My only theory right now is that BE-86 is slower than some of the other powders I’ve used and is still at a decent pressure when the bullet is in the last inch of the barrel, giving the bullet an additional speed boost.