I just received a new 38 Super upper for my Witness and thought I'd start a thread regarding 38 Super and 9x23 loads in the Witness pistols.
First of all, I'm not suggesting that the Witness pistols are designed to shoot 9x23...they aren't. 38Super runs about 35,000 psi, while 9x23 runs about 46,000 psi... a significant difference. Also the 38Super is a straight walled case, while the 9x23 is a tapered case, so the chambers are not the same. SAAMI shows shooting 38Super in a 9x23 chamber to be an unsafe practice, but does not show shooting 9x23 in a 38Super to be an unsafe practice. Does that mean it's safe? NO. If you go down this path, you do so at your own risk. Also, there is not much published data on 9x23 loads, so anything listed here should be considered experimental and used at your own risk.
I look forward to the input from others.
If the moderators feel this thread is inappropriate, please remove it.
First a picture showing cross sections of various 38Super brass versus Winchester 9x23 brass:
Wanting to see what the effects of the lower case volume would be, I started with a mild 38Super load of 4.9gr of VV N320. All cartridges were loaded to an OAL of 1.250 with a Hornady HAP 125gr JHP (.356) and Federal Small Rifle primers.
Remington 38Super +P nickel:
868.5 fps
354.3 ES
132.6 SD
Not enough pressure for efficient burn.
Starline 38SuperComp:
1083 fps
130.6 ES
45.33 SD
Better, but not great.
Winchester 9x23:
1139 fps
52.64 ES
16.67 SD
Now we're getting a more efficient burn, but I'm also almost at case capacity. No bulging or case deformation. If it wasn't for the dented primer, powder residue, and chamber scratches, you wouldn't even know it was a fired case. Lighter recoil than factory Remington 38Super 130gr FMJs.
For comparison, factory Remington 38Super 130gr FMJ load:
1145 fps
81.78 ES
25.76 SD
I should also note, I had three restrikes in 100 rounds on the Federal Small Rifle primers with a 15lb mainspring. I'll be increasing to a 16lb mainspring. At this point I think the Small Rifle primers were overkill, but I was playing it safe.