My first attempt was to paper patch my smooth shank 0.378" as cast bullets. This did not go well, the casualty rate amongst the paper patched bullets was very high, and it took a long time to get just six bullets right for testing.

Using a 0.378" bullet, paper patching it, and trying to size it back down to 0.377", caused the paper to be scraped away from the bullet shank in the bullet sizing die. Firstly, the bullet was not the best as cast size for paper patching.

The sizing die I used was a Lyman .377 lube sizer die, in a push through configuration. It has holes in the sides. My paper was being pressured into the holes, and tearing off. Secondly, the sizing die was not the best for sizing paper patch bullets.

Marginal accuracy results were achieved with the 245 grains with two wraps of paper. not as good as with three wraps at higher velocity, but much better than the smooth shank 0.378 lead.