Trying to work up a load for my 7mm Rem Mag using 140 gr. Barnes Triple Shocks I used some brass that I had pulled bullets from. The necks did not get resized after pulling the bullets and before I seated the TSX's. I was a little disappointed with the results I got with these rounds, so I'd like to know if I screwed up by using this brass. In other words, should you resize the necks of brass that you pulled bullets from before seating new bullets?

These were reloads I pulled the bullets from, not factory ammo. They were not crimped. Out of this rifle I'm pretty much used to 1/2 to 1" groups at 100 yards. I was getting 1.5" groups. I'll try this same load in newly neck-sized brass and see if that helps. The Triple Shocks have been very accurate in my other rifle. Thanks for your comments, guys.

What were the results you were so disappointed in? If they were 3/4-1" at 100yds, I would say it's doing well for that caliber and bullet. If you're trying to get .25 out of a stock gun in that caliber, you're expectations may be a bit high. Let us know...

Curious if this was factory ammo you pulled the bullets from....if so you may have to removed the crimp to get the bullets to seat correctly. Why not load those bullets in a new brass loaded up from scratch ? When ever I tried pulling bullets (for whatever reason)it always appeared to me to reduce the neck tension if I didn't at least neck size them before reloading them.
I am just now getting ready to work with my first batch of triple shocks.....wondering how the grooves line up with the top of the neck. In my particular chambering I suspect they will be exposed as opposed to located down in the neck. How did yours end up?

Neck tension DOES affect accuracy. How much, it really depends on the load. If I'm looking for consistency and accuracy and not just pulling the trigger and making noise, I always neck size the brass after pulling bullets. The neck of the brass is like a rubber band. It stretches and doesn't quite return to its former size after each stretch. I just pull the bullets, put the propellant in a pan, then neck size without the decapper. Leave the ball on there. If you have a bushing die you don't even have to dump the powder.