Hi all.
I am hoping to leverage someone's knowledge and experience to help advance my load development methodology for a non-SAAMI wildcat cartridge. Specifically, this is for a Kimber 8400 with a 23" Pac-Nor 1/10 barrel chambered in 257 WSM (not to be confused with 25 WSSM). I had this built back in approximately 2005.
I have achieved fair results with RL22, IMR 4831 and most recently MagPro with some TTSX monos. I don't believe that I have reached the ceiling yet for any of the loads. I used to use some software titled "Load from a Disc" but it doesn't appear to be supported anymore at least for the platforms that I use. Absent software, I compared other similar type cartridges in terms volume, bore diameter, and projectile BCs to get me in the ballpark. Is it reasonable to compare to a cartridge like 257 Weatherby Mag and adjust for case capacity to create a starting load?
E.G. - If the Weatherby case has 12% more capacity, can I reduce the theoretical starting load for the 257 WSM by 12% and be in the same starting range? Is Ramshot Hunter or RL19 is too fast? My supply of RL22 is nearing its end...
Guy - I believe that I read your article and saw a previous post about you trying Hunter with a 244 REM. That seems to be a relatively similar comparison in terms of high powder volume to bore size but not necessarily charge weights. Were you happy with the results?
Ultimately, I am pleased with what I have accomplished so far but it's been painfully slow and many trips to the range. I am curious if there is a more efficient way of doing this other than buying more software. If not, that's ok too. I think that my current loads behave more like a 25-06 on steroids which ain't bad. I have only killed 2 whitetails at approximately 150 yards with this rifle and 115gn NOS BT and the terminal performance was excellent; however, I don't think that distance is a true test of its capability.
Since I was operating in uncharted waters, I believe that I stayed conservative in all of the loads and didn't experience significant pressure signs other than primers starting to flatten out a little on one of the loads. I don't remember exactly which one without my notes in front of me.
Example Loads/Velocities:
1. Norma Brass
58 gns RL22
NOS 115 BT and NOS 110 AB
AVE Velocity - 3200 FPS
Average group (3 shot) - 1"
2. 60 gns IMR 4831
80gn Barnes TTSX
AVE Velocity - 3679 FPS
Average group (3 shot) - .9"
3. 63 gns MagPro
100gn Barnes TTSX
AVE Velocity - 3300 FPS (seems a little slow)
Average group (3 shot) - .9"
Sorry for the lengthy and tedious post and please humor my glamour shot. Have a good weekend and stay safe.
Respectfully,
JMRhino
I am hoping to leverage someone's knowledge and experience to help advance my load development methodology for a non-SAAMI wildcat cartridge. Specifically, this is for a Kimber 8400 with a 23" Pac-Nor 1/10 barrel chambered in 257 WSM (not to be confused with 25 WSSM). I had this built back in approximately 2005.
I have achieved fair results with RL22, IMR 4831 and most recently MagPro with some TTSX monos. I don't believe that I have reached the ceiling yet for any of the loads. I used to use some software titled "Load from a Disc" but it doesn't appear to be supported anymore at least for the platforms that I use. Absent software, I compared other similar type cartridges in terms volume, bore diameter, and projectile BCs to get me in the ballpark. Is it reasonable to compare to a cartridge like 257 Weatherby Mag and adjust for case capacity to create a starting load?
E.G. - If the Weatherby case has 12% more capacity, can I reduce the theoretical starting load for the 257 WSM by 12% and be in the same starting range? Is Ramshot Hunter or RL19 is too fast? My supply of RL22 is nearing its end...
Guy - I believe that I read your article and saw a previous post about you trying Hunter with a 244 REM. That seems to be a relatively similar comparison in terms of high powder volume to bore size but not necessarily charge weights. Were you happy with the results?
Ultimately, I am pleased with what I have accomplished so far but it's been painfully slow and many trips to the range. I am curious if there is a more efficient way of doing this other than buying more software. If not, that's ok too. I think that my current loads behave more like a 25-06 on steroids which ain't bad. I have only killed 2 whitetails at approximately 150 yards with this rifle and 115gn NOS BT and the terminal performance was excellent; however, I don't think that distance is a true test of its capability.
Since I was operating in uncharted waters, I believe that I stayed conservative in all of the loads and didn't experience significant pressure signs other than primers starting to flatten out a little on one of the loads. I don't remember exactly which one without my notes in front of me.
Example Loads/Velocities:
1. Norma Brass
58 gns RL22
NOS 115 BT and NOS 110 AB
AVE Velocity - 3200 FPS
Average group (3 shot) - 1"
2. 60 gns IMR 4831
80gn Barnes TTSX
AVE Velocity - 3679 FPS
Average group (3 shot) - .9"
3. 63 gns MagPro
100gn Barnes TTSX
AVE Velocity - 3300 FPS (seems a little slow)
Average group (3 shot) - .9"
Sorry for the lengthy and tedious post and please humor my glamour shot. Have a good weekend and stay safe.
Respectfully,
JMRhino
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