I had a chance to go out to the rifle range yesterday to test out a few of my 505 Gibbs loads. Out of 19, I had 3 or 4 hang fires (all using the H4831SC powder)along with 4 dented necks as seen in the picture below. I've seen this on the case bodies before but never on the necks. Two of the dented necks were using IMR4831 and the other two were from H4831SC.I chronographed the loads and came up with one string that was 2021, 2036 and 1710fps.(the latter being one of hangfires. Though the IMR powder seemed to work out better than the Hodgdons, it still doesn't explain the neck dents from both powders. I'm beginning to think that it is a primer problem. When I first primed a few cases, I didn't have a large enough head for my hand priming tool for this big of case so I had to use the RCBS rock chucker primer attachment and found that I had to bang the handle a few times to seat the primers because they protruded a little. I may have crushed the primer anvil on a few of them. I finally received my new tool head and the primers seated easy.