Loaded my 32-20 with too much Bullseye

by Bob Hatfield , Sunday, September 24, 2023, 17:34 (424 days ago)

Went to load some 32-20 with a new batch of Bullseye and a 100 grain Vance .313 RNFP bullet. Normally use a No. 5 RCBS little dandy rotor and dump 3.5 grains of Bullsye. I weighed it and it was really low. So I tried a #6 rotor and it was under 3.5 so I thought this is a less dense batch. Like a dumba$$ I used the No.7 rotor and my RCBS 505 scale said "3.5 grains" without double checking on another scale.

I shot about 20 of these the other day and they using a Smith & Wesson M&P 32 (Winchester) revolver made in the late 1920's so it should be heat treated. They shot to the point of aim at 15 yards and shot around a 2-1/2 inch group at 25 yards just a little high. I noticed they felt sort of peppy. I proceeded to blast down 6 plates at 50 yards. When I got home I checked the powder weight on an electronic scale and they have 4 grains of Bullseye in them. Just like the little dandy chart says a #7 dumps LOL.
So I guess I'm probably over 20,000 psi in this old Smith. I'm going to chronograph a few to get an idea as to what the velocity was before I dismantle the other 80 of them. The cases didn't show any signs of stress and leading was very little. Those chambers are pretty thick on the 32-20 Smith but the gun is over 95 years old.

My RCBS scale was out of whack and the powder is OK.............Dang

Bob