When I got my Rock Chucker, I primed my cases with it, same as you are doing. I had to inspect each primer after seating, to ensure they were seated properly and to look to see if they were crushed. There is so much power there that you do not have a good "feel" to tell when a primer is properly seated. When I found a high primer, I would just stick it back in and give it a little more push on the handle to seat it all the way down. Some times I would crush a primer. You do learn to work with it after a while, I primed a lot of cases that way. I eventually got a priming tool. Lee makes a good one, but I got a RCBS tool and it has served me well. Later down the road (much later) I got a RCBS Trim Mate. When I did, I took all of my new brass and run them over a pocket uniformer. Stubborn primers to seat became thing of the past. The uniformer will cut the sides a little too if they are small and the square up the bottom of the primer pocket so it is the same diameter all the way down. I have used a hand tool to do this with, but it was a lot of work and I got sore hands trying to hold it. In every thing that is made, there are tolerances plus or minus so much for each component. If you get cases with tight primer pockets and primers that are on the high side(diameter wise) they can be pretty hard to seat. I had a batch of Winchester 223 cases that I had a real hard time seating in some Remington 7 1/2 primers. After I uniformed the pockets, they were much easier to seat. It was after that experience that I started to uniform all primer pockets; first with that dang nab hand tool, then with a Trim Mate (much easier). Just my 2 cents Good Luck and good shooting