Experimenting with old sixguns.....
A while back, I traded for a S&W Model 1917 that he had that was done up by Hamilton Bowen. Bowen took a 4" .38/44 Heavy Duty barrel and re-bored it to .452" with a 1 in 16" twist, mounted it on the M1917 frame, and then put a half-moon front sight blade on the barrel that was regulated for hard-ball, then re-marked the barrel and re-finished/re-blued the whole gun. This is one very sweet little N-frame!
The only problem is, it has the original M1917 cylinder on it. Chambers are OK, but the throats run .455"-.456" (and on the M1917 the throats are l-o-o-o-n-g, so an undersized bullet has plenty of time to rattle around before it finds the stability of the lands/grooves). 200s shoot a couple inches low, and accuracy is so-so (bullets were "sized" .454", but they are not really that big, so this is a something of a fantasy). It is logical to expect heavier bullets to shoot higher, so I have some 220 grain TC-HPs loaded up, as well as some 454424 (Keith SWC). For the Keith SWC, I used the published load data for the 260 grain JHP (Hogdgon and Speer, 5.8 or 6.4 grains of Unique max) and used that as a guideline for the 247 grain cast bullet and went with 5.5 grains of Unique. I'm expecting something like 750-800 fps. And this bullet is truly sized .454" (and drops from the blocks fat enough that it can be sized larger, if need be). Let me tell you guys, the Keith SWC looks extremely business-like when loaded into the .45 ACP case....