Cast bullet over size .

.001-.002 oversize usually isn't a problem for cast, it's actually preferred. Have you slugged your barrel to see actual size?

I have a T/C Encore in 454 it was one of the last barrels to come out of the custom shop I'm sizing to .452 G/C this is at 100 yards

The mold is from MP the hp boolit is right at 300gr if I flip the pins to make a solid boolit it's 330 ish I have same mold but for my 44 were the hp
is right at 265 ish gr and the solid is pushing right around 300gr

link to MP https://www.mp-molds.com/

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