I took a good friend to the range for some plinking one day. There were two Handi rifles along. One in 357 and one in 30-30. Yep, he fired a 357 in the 30-30. Surprisingly the lead bullet swaged down enough to exit the bore and the case split like the ones pictured above. I've quit being concerned if cast bullets are a bit larger than the bore slugs if they chamber with a couple thousandths clearance Gp