It is not uncommon to have tight primer pockets. If you are new and unfamiliar with the Lee priming tool, try rotating the case 90 degrees and trying to seat the primer again. Once in a while the primer will start a little bit crooked. If you rotate the case 90 degrees, it will straighten the primer out and it will go right in. I found this out when seating primers in 5.56 brass that I may not have removed all of the primer crimp.
Make sure you have a little petroleum jelly on the levers and moving mechanism of your ram prime. Makes it work lots smoother. You will also get a little better feel of what the primer is doing.
I have had cases that I had to use both thumbs to seat the primer. You can put a lot of pressure on the primer with that tool. If all of the primers are going easy, that could also be bad.
Steve