I am sorry if i missed replying to anyone.
The brass that came with the factory Seekins rifle was not resized. I was under the impression that if i kept the same brass it would create consistency with measuring throughout all reloads with my 6.5 PRC. They way i understood shoulder bump was, you take a fired brass and put it in the comparator gauge. than you zero that one out. Than you take the brass you want to resize and it should measure .000 but mine was measuring -.002. I do not have a neck resizing die only so i used my FL resizing die. after that i was getting -.001 and some cases where -.003.
It seems one error is using once fired brass as my control and not using brass from the batch of 3 times fired.
As far as measurements, I will try to measure with my calipers but i do not have any other way to measure my brass at this time.
I hope this helps, and i apologize for confusion. I am trying to explain a problem over the internet that i personally do not understand myself. I did not have this issue when they were 2x fired brass.
I am still rather confused by your explanation.
Shoulder bump is simply that. Bumping the shoulder back to ensure the rounds chamber. With a FL die that will also constrict the brass at the shoulder and near the rim of the case. Assuming the die is set up properly.
When I am setting up my die it can be broken down into a couple simple steps.
1. Screw die down until it meets the shell holder.
2. With a comparator gauge, measure the fired brass. I look for consistency so if several read the same number I zero the calipers to that number.
3. Lube cases. I like Redding sizing wax.
4. Run cases into the die. If the number is anything other than a negative number the die is screwed in a little deeper. Don't size the same piece of brass over and over. Set the ones that did not get bumped back enough to the side and resize them once the die is set correctly.
5. Keep adjusting die down until desired bump is achieved. I aim for .002-.003 for most bolt actions.
I am not a pro level shooter or benchrest competition guy. I load ammo for my hunting rifles and want to ensure rounds chamber at all times so a neck sizer is worthless to me. A properly set up FL sizer that bumps the shoulder back .002-.003 is the only way to go for hunting ammo in my opinion.
This is my process and I know folks do things a little different. I also load for a Seekins 6.5 PRC and doing this process works well enough for me and achieving accurate and consistent ammo is pretty straight forward.
