Well if you read my post about Marlin barrels that might be oversized now in 44 Remington Mag , we can not assume the bore size.You might well have a 431 barrel there for require a 432 bullet to make it right. :xSpang said:I use .431 for most of my lead bullets. I size them using the BCBS sizer and measure to find .431. My Lee mold cast them at .431. I have had good luck with this size bullet in Rifle and Revolver.
Work with in what ? =or _ of what bore size the 429 or the 431.Guest said:SAAMI specifically states that the groove dimension for 44 Rem. Magnum "RIFLE" barrels is .431. This is not new and has been in place for many years. SAAMI does not recommend dimensional tolerances on bore size. I have spoken to Marlin folks and they advise that they work within +/- .001. Sounds reasonable to me.