+++++ 7.5x53.5 mm swiss (gp90) +++++
- Thread starter weimajack
- Start date
For SR 1889. (HAve not loaded for M93 model)
Brass:
I leave mine at 55mm length. Helps prevent blow-by and improves neck tension and powder burn.
Bullets:
.308 is fine. Prefer longer bullets 170gr+. Used 178gr Amax with VG accuracy. I prefer to keep it simple.
Powder:
Prefer medium burn rate with Jacketed bullets. H4895, IMR 3031, 4064 etc.
I use ± 80% of max recommended loads for 7.5x55 (GP11)
EG : H4895 43.75grs in 7.5x55 Gp11 loads
80% for GP90 =35grs of H4895
Brass:
I leave mine at 55mm length. Helps prevent blow-by and improves neck tension and powder burn.
Bullets:
.308 is fine. Prefer longer bullets 170gr+. Used 178gr Amax with VG accuracy. I prefer to keep it simple.
Powder:
Prefer medium burn rate with Jacketed bullets. H4895, IMR 3031, 4064 etc.
I use ± 80% of max recommended loads for 7.5x55 (GP11)
EG : H4895 43.75grs in 7.5x55 Gp11 loads
80% for GP90 =35grs of H4895
Loads should be safe. My only concern with the M93 is whether the throat is the same profile as the 1889.
I would load one with case length at 55mm with bullet short of the rifling, and see what , if anything happens to the case mouth.
Or if you have corn meal, make a blank case forming load with a 12 or 13 gr fast pistol powder, corn meal on top of powder, and melt a candle over the cornmeal in the case mouth, fire it in rifle and see if the chamber is shorter than the 55mm case length.
M93 rifle itself should be much stronger than the 1889.
I would load one with case length at 55mm with bullet short of the rifling, and see what , if anything happens to the case mouth.
Or if you have corn meal, make a blank case forming load with a 12 or 13 gr fast pistol powder, corn meal on top of powder, and melt a candle over the cornmeal in the case mouth, fire it in rifle and see if the chamber is shorter than the 55mm case length.
M93 rifle itself should be much stronger than the 1889.
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I reload for my 1889 & 1893.
I have trimmed PPU 7.5x55 brass but as noted above it's not strictly required. If it chambers easily it should be ok. I trimmed just because I can and wanted proper ammo.
30 grains Varget under a 220 grain Hornady .308 long nosed bullet. This is about as close as you can get to Gp90 without paper patched bullets!
Very accurate from my 1889.
I have trimmed PPU 7.5x55 brass but as noted above it's not strictly required. If it chambers easily it should be ok. I trimmed just because I can and wanted proper ammo.
30 grains Varget under a 220 grain Hornady .308 long nosed bullet. This is about as close as you can get to Gp90 without paper patched bullets!
Very accurate from my 1889.
