McFred
07-03-2020, 03:05 PM
I spent the weekend working up a load for a Glock 31 in 357SIG using the LEE 358-125-RF. The alloy is air-cooled wheel weights, sized to .358" and tumble lubed with 45/45/10.
https://i.postimg.cc/CMbXCk2f/358-125-RF.jpg
I used weight-sorted Federal .40 S&W range brass with Remington 5.5 primers. I was surprised to find that these small cases vary by nearly 500mg (~8gr). I cherry-picked a set of 150 that weighed within 50mg at an average weight of 4.140 grams. I care about this as I am using a *full* case of WC297 surplus ball powder to set the bullet on. Variation in case capacity affects the seating depth. Bullet setback from the short neck is a non-issue.
https://i.postimg.cc/V6MsPcZq/castG31.jpg
In my G31, these bullets' ogive touch the end of the chamber at 1.130" overall cartridge length. At 1.130" with my selected Federal cases, I can fit 12.75gr of WC297, which burns cleaner the more you put in. In testing, I ran up to 14gr jamming the projectile into battery and got no signs of over pressure, yielding 1377fps average, unfortunately, this OAL will not function reliably in this semiautomatic.
With 12.75gr the pistol seems to function well from a magazine and after 50 rounds the polygonally-rifled bore is as shiny as new. Average velocity is 1135fps. With 12.75gr commercial Win 296 it leaded the bore and yielded 1113fps average as a point of comparison.
Primers look fine:
https://i.postimg.cc/jS5sdfkd/cast-primers.jpg
Some considerations:
• I'm actually using the projectile, neck tension and the powder column to control headspace, not really the case mouth or the shoulder.
• I'm bumping the shoulder on the cases back about .010" from fired cases. This may seem excessive, but it gives enough slop that any powder-fouling in the chamber affects function less than with tighter chamber tolerances.
• Different alloys or lubes may permit different loading procedures, this is what's worked for me. 12.75gr W296, 12.3gr AA#9, 6gr-7gr Unique, and 4.5gr Bullseye all leaded the bore at similar low pressures and velocities. In an aftermarket cut-rifled barrel I never was able to keep it from leading the bore.
Lastly, the fireball seems appropriate for Independence Day weekend:
https://i.postimg.cc/qBx0swPv/cast-fireball.jpg
https://i.postimg.cc/CMbXCk2f/358-125-RF.jpg
I used weight-sorted Federal .40 S&W range brass with Remington 5.5 primers. I was surprised to find that these small cases vary by nearly 500mg (~8gr). I cherry-picked a set of 150 that weighed within 50mg at an average weight of 4.140 grams. I care about this as I am using a *full* case of WC297 surplus ball powder to set the bullet on. Variation in case capacity affects the seating depth. Bullet setback from the short neck is a non-issue.
https://i.postimg.cc/V6MsPcZq/castG31.jpg
In my G31, these bullets' ogive touch the end of the chamber at 1.130" overall cartridge length. At 1.130" with my selected Federal cases, I can fit 12.75gr of WC297, which burns cleaner the more you put in. In testing, I ran up to 14gr jamming the projectile into battery and got no signs of over pressure, yielding 1377fps average, unfortunately, this OAL will not function reliably in this semiautomatic.
With 12.75gr the pistol seems to function well from a magazine and after 50 rounds the polygonally-rifled bore is as shiny as new. Average velocity is 1135fps. With 12.75gr commercial Win 296 it leaded the bore and yielded 1113fps average as a point of comparison.
Primers look fine:
https://i.postimg.cc/jS5sdfkd/cast-primers.jpg
Some considerations:
• I'm actually using the projectile, neck tension and the powder column to control headspace, not really the case mouth or the shoulder.
• I'm bumping the shoulder on the cases back about .010" from fired cases. This may seem excessive, but it gives enough slop that any powder-fouling in the chamber affects function less than with tighter chamber tolerances.
• Different alloys or lubes may permit different loading procedures, this is what's worked for me. 12.75gr W296, 12.3gr AA#9, 6gr-7gr Unique, and 4.5gr Bullseye all leaded the bore at similar low pressures and velocities. In an aftermarket cut-rifled barrel I never was able to keep it from leading the bore.
Lastly, the fireball seems appropriate for Independence Day weekend:
https://i.postimg.cc/qBx0swPv/cast-fireball.jpg