Well first of the gun is a Savage 12 LRP and I am disabled so I'm currently benching at 100yds and want to go out to 1000 eventually. I am starting with new Lapua brass.

I am unfortunately limited to bench. I'm using a full length Hornady Custom Grade two die set. This is the only one rifle of mine in 260 so I could neck size only, but not sure if that is a 100% advantage or not from all that I have read, I know your brass will last longer, but in my case don't know if that is the number one priority. I have a Hornady Headspace Comparator that I have used for the first time and have set the sizing die to bump the shoulder about 1-1/2 - 2 thousands from a fire case. I don't remember for sure what the O/D was on the neck of a fire case (next time will document) but I think it was either between .297 & .298 or between .298 & .299. It seems like I read somewhere that when resizing with a neck bushing die set you wanted to be around 4-5 thousands under your fire brass.

I remember thinking that .292 was good and that was what the new brass was, and when I first got the new brass somewhere I read to run the expander through the brass for concentricity so I did. Also when I re-sized the once fired brass, the first few rounds that I checked with the calipers were around .292 so I just ran the whole 100 out and then proceededed priming and reloading. The first reloading went ok and had some developmental loads that did less than 1/2 MOA which is what I duplicated this time when I noticed the tight tension. So after about the sixth tight tension is where I stopped and discovered most of the O/D's were running .291-.291.5.

I decided (not sure if it was a good decision) to just run the expander in and out of the mouth, and in doing so that changed them to around .292-.292.5, and then started loading and it everything seemed fine like it did the first reload.

Let me know what you guys think.