I loaded two separate rounds both based on 48 grains of H4895, I used 400 hard cast lead RN and speer 350 grain jacketed FN. Published velocity for the 350 was 1450FPS, I would need to check what the velocity on the 400s but I would guess a 100 fps less.

My sp22 is equiped with the NECG ruger peep.
Recoil was mild with no flat primers or stuck cases, most times the cases fell out when the gun was tipped.
I left the targets at my shooting place but i shot a total of 50 rounds. There was little difference in point of impact between the two bullets most patterns of 10 bullets hit in the same area which was under 10". Many bullets keyed holed previous shots and when I was checking between shots I would guess both barrels hit under 2" of each other. When I moved out to fifty the pattern stayed pretty much the same probably because the smaller target made me concentrate a little more. The shooting was done offhand or on a single shooting stick so the pattern should improve on a triple stick or rest.

Likes/dislikes
The failure of the action to stay open enough to drop out or load the shells
The trigger pull on forward (right) barrel needs to be shortened
The peep site is the way to go
The stock pistol grip must be made for a orangutan since you need finger 7" long fingers to grip the stock and touch the trigger
No trigger guard impacts on the shooting hand but if you hot load the rounds it probably will.
The weight of the gun makes it feel like a 410, as a matter of fact a friend of mine originally thought it was

Thanks for the imformation. I'm about to shoot mine and have some 4895 on hand. Now I have a place to start. My goal is to get a 405 fast enough to be downright deadly, but preassure low enough for the cases to fall out.

The biggest thing I found to help getting the gun to stay open are the cocking tabs. Grind/file them down until the hammers cock as close to the end of travel as possible. THat combined with lightening the main springs will allow the gun to stay open.

I said the same thing to myself when I first saw the pistol grip. Can't even grip at the checkering when shooting it.

I added lead to the butt stock on my 30-06 and it balances well. I don't think it will work on my 45-70 because it feels muzzle light compared to the '06. Maybe some weight under the ribs????

If you don't mind, I would really be interested in hearing any future results of your loading/shooting.

Mike