I was shooting a match yesterday and had a few rounds make an oblong entry. Two rounds that I know of, possibly more. The holes were quickly pasted over so I didn't get to have a good look. I also had three consecutive misses on a steel target at 10 yards that I cannot account for.
I slugged the bore and the groove diameter measures .355" and my bullets were sized .356" The rifling is somewhat different on the gen 5 17.
Load is Lee 356-120-TC over 4.5 gr. Auto Comp, COAL: 1.030". Hardness is around 11. I'm getting moderate leading but nothing a copper chore boy over a brush doesn't fish out. Has anyone else had a chance to play around with the gen 5?