I said wear,not run out.When you test the loaded rounds for run out,you are testing your prep,the brass,the dies,and maybe the press. If those first three are right,99 44/100% of the pressses will likely work fine.
A press is a simple machine,the two holes must be straight and line up.Since the sliding fit will the same for 1 1/4" as for a 5/8" the fit percentage of the diameter will be larger in the smaller ram,more slop.Deeper the hole for the ram, more bearing surface, less slop.Slop may not be all that bad,consider it as a self -alaigning feature.
