Just a FYI. Safe amounts of powders like H4198 will get a 275gr bullet out of a 45/70 conversion at well over 2300fps. You can easily break 2500fps with sabot loads. These are simple low peak pressure loads. 58gr of N120 for example is well over 2600fps with a 200gr bullet in a sabot. I dont think that load even makes 33kpsi. Small amounts of N110 are faster than max loads of BH209 and rock solid dependable in nearly any temperature.
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