Re: .45-70 Question
The 405 gr. Bullets were developed for the short barreled Trapdoor Springfields which had slow 1:22 twist barrels. The Buffalo Rifkes such as the Harps and Rolling Blocks had slower twists in the 1:18-1:20 range to handle the heavier 500+ grain. My Shilo Sharps 45-70 has a 1:18 twist. I shoot almost exclusively 525 gr.cast bullets and it's quite accurate. I have also shot Hornady 400 gr. Jacketed bullets in it and while the twist was fast, it shot them well with no key holing. An important factor if using 405 gr would be to make sure "hard cast" lead bullets have at least 1:20 tin content. Soft lead will strip in fast twist barrels. Also, if your bullets are cast, you need to check the diameter sizing. The fit has to be right and the molds, and finished bullets have come in varied sizes. If you want a great reference for shooting these rifles and how to load for them get, "Shooting Buffalo Rifles of the Old West" by Mike Venturino.
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