Nope, they aren't oversize that much, and I'd think are too close for a rebore job. The 44 shoots fine, just needs to have proper size bullets. This is even more important when using cast bullets, but Mine shot the 300 grain Hornady XTP, a .430 bullet and the Speer 270 Gold Dot bullet at .429 just fine. Lots of folks out there offer bullets of sizes from .427-.432 for the 44 caliber Shouldn't be a problem to get a 44 Handi to shoot good, really good.