It's not the .452 size giving you trouble. I shoot almost exclusivly lead in my 45's and have been sizing to .452 for many years.
You didn't mention what bullet you're using, or if you checked dimensions with a caliper. I suppose you could be seating the bullet too deep and bulging the case. I get that sometimes with revolver cartridges (without seating too deep) but never with an auto cartridge. The reason it happens with revolver cartridges (at least) is that the sizing die takes the beass to smaller than factory dimensions. I did get a box of commercial cast bullets a few years ago that were oversized at .453-.454, mistakes happen, tooling wears. I just resized to .452 and went on my merry way.
Check weight before loading a new batch of bullets, and dimensions before, during & after loading and you'll not be wondering at these things. From the lack of mention in your post about calipers...I take it you do not own any. I'm telling you, if you get some calipers and check all dimensions, the problem area will become evident! Lacking funds for calipers right now? Take your case gauge and a handful of rounds into your local gunshop and they might let you do a few checks with theirs. The case gauge might even be undersized.