Although the Kirst converter for the 51/61 Navy is marked 38LC, that is the cartridge it will chamber with a full length bullet load. It will chamber and fire 38 hollowbase wadcutters with ease, and that's all I shoot in mine. The Hollowbase wadcutter is seated flush with the case mouth, so it is short enough to chamber. The cylinder will actually chamber a 357 magnum case with a full wadcutter bullet as well, I tried it. Unless you shoot the hollowbase bullet, it will not shoot accurately without relining the bore to 357. Mine shoot hollowbase bullets as accurately through the 375/36bore as a modern 38 special revolver does. If the brass is relatively fresh and the load is right (3.1 or 3.2 of Bullseye, 231 or Titegroup), the cases expand and stay in the chambers without slipping back and jamming, in most guns. A friend has two that slip back every time, and mine does not. The only difference I can determine is that his chambers were polished better than mine, so are probably more slippery. We swapped ammo and it made no difference. The 38 special with a HBWC will probably expand better and stick in the chamber better than 38LC, but that's just a guess. I have designed and intend to build a loading gate for the Kirst.
