WB
There was a .375 Bobcat but I think it was
Wednesday, May 18, 2022, 09:49

based on the .220 Swift which has a small rim, and is about the same size as the .30-30. I think also a shortened version of the .375 Supermag to fit a 1.75" cylinder. Both wildcat rounds.

You can make .401 Herters from .30-30 brass, it's just a bit more involved than some others. My best .401 WSL rounds are from 7.62x39mm blown straight. Some have used .30-30 brass. I also have used modified .41 Rem. cases with long seated bullets, and modded .414 SM brass to make perfect replica factory .401 WSL (0.406 - 0.408" bullet) cases.

The .375 is interesting. The .375 Win. is a good round, much better to me than the .38-55 Win. that had wildly variations in bores. Up to 0.380"! Starline makes extra thin necked cases to compensate for fat .38-55 cast bullets. It's a boon to the Reeder designed .400 GNR round and my choice for making cartridges. .30-30 brass can vary wildly as to rim "thickness" as well as neck wall thickness. I've hit many a snag goofing around. One time I even CAREFULLY deepened my Contender barrel rim recess 0.003" to allow for these variations and make my life easier on a fancy custom barrel. Not for the faint of heart or shade tree machinist.

I once made some "rimmed" 10mm Auto rounds and made them work. But it was not easy. Pawl gears necessitate very small rim diameters (on L-frame size guns) and the case is very thick on a .30-30 that far down, requiring much inside case reaming. This experiment was to make rimmed rounds so I did not need full-moon clips. Another hurdle was headspace. I had to thin the rims to a point that they could not be used for headspace, I used the case mouth for that, and simply used the rims for ejection. But the cylinder closed and they did not drag. Easier to show than explain, but it was fun to try and make some.