I dug the following up from The Fouling Shot Archives. As usual, if it has anything to do with the “Bunny Gun” calibers, C.E. Harris has been there, done that and designed the T-shirt.
TFS 61-24 (J.K. Bair)
Update on Walther GSP .32 S&W : Update of TFS 54 article
Alberts .32 cal. 100-gr HBWC - 1.0 - Bullseye - 50 feet
Alberts .32 cal. 100-gr HBWC - 1.8 - Bullseye - 50 yds
The author was loading for match shooting, so these loads should be good.
TFS 39-23 (C.E. Harris)
Colt .32 OMT: A Pleasant Shooting Old-Timer: .32 S&W Long tested in Colt Officer's Model Target revolver
Hornady 90-gr SWC - 2.1 or 2.8 - WW231 - 720 fps or 859 fps
H&G 65 (98 gr) - 3.5 - Unique - 982 fps or 2.7 - Bullseye - 966 fps or 8.5 - WW296 - 1202 fps
Alberts 100-gr HBWC - 2.4 - Unique - 830 fps
Alberts 154-gr Schuetzenplinker - 2.8 -WW231 or 7.0 - WW296 - 820 fps or 1008 fps
90-100 gr bullets over 850 fps for large-frame revolvers only
TFS 40-11 (C.E. Harris)
.32 S&W Long is a Rifle Cartridge Too: 154-gr bullets in Remington 788 rebarreled (1-10” twist) to .32 S&W Long (.32 S&W Long Rifle, .32 S&W LR)
Alberts 154-gr Schuetzenplinker, Welsh 15-309B (154 gr) - 10.5 - RL7 - 1.5” COL - 1100 fps
Lyman 311291 (175 gr) - 8.5 - RL7 - 1050 fps
Alberts Schuetzenplinker - 8.0 to 9.0 - WW296 - 1150 fps - 10” Contender
150-gr plain-base - 7.0 - WW296 - 1150 fps approx.
"”¦I then took the154-gr. Alberts Scheutzen plainbased bullet and seated it way out to 1.5” overall and stuff(ed) the case with all the RL-7 it would hold. The charge was 10½ grs. This gave ragged hole accuracy a t 25 yds. and gave better accuracy than any rifle to date with this Alberts bullet."
"I'm calling this load the .32 Long Rifle, because of its greater overall length, and to distinguish it from .32 S&W loads intended for revolvers."
"Although most of my testing to date has been with the 154-gr. Alberts bullet, the .32 LR should work well with plainbased or GC cast bullets of less than 180 grs. Limited trials of the #311291 and NEI 182-308 gave good results with charges from 8½ - 10 grs. of RL-7. Also good is a caseful of 4198 or SR-4759. These powders are bulky enough you can't cram enough in the case to get into any trouble."
”With the heavy bullets you get higher pressure and velocity than in shooting the 154-gr. Alberts. The 10½ gr. load of RL-7 gives about 1100 f.p.s. with the Alberts bullets, and I got no perforations of Federal 100 pistol primers. When substituting the #311291 with the same charge, velocity jumped to 1220 f.p.s. and I got a few pierced primer cups. Therefore, I'd suggest using rifle primers with the heavier bullets, or cutting back the load, preferably the latter. An 8½ gr. charge of RL-7 will give about 1050 f.p.s. with the #311291 or similar."
The only problem I see with using the above .32 S&W LR loads is that they might produce enough pressure to bulge or permanently expand the chamber adapter. If that happens, you might be able to resize the adapter in a standard .303 resizing die, but I wouldn't bet on it. Maybe Mr. Harris will weigh in on the subject. I personally don't see any problem with using the pistol loads listed above. The .303 has a 1-10” twist, so at the velocities you will be getting, stability probably won't be an issue. If I could scrounge some range pick-up .32 S&W or .32 H&R Magnum brass, I'd probably give this a try.
I originally chose the Speer wadcutter because it was a 0.314” diameter island in a sea of 110-gr., .308” Carbine bullets. I was amazed at how well it shot at 50 yards. The hollow base might expand to give a better bore fit, but I never recovered a bullet to look at and the landing probably messed it up.
Whatever happens, write up your experiences and submit them to The Fouling Shot.