One more thing; DON'T USE A DREMEL TOOL! They can get away from you and do a tremendous amount of unrepairable damage to your lock inlet and the surrounding area. Now, if you are very experienced with the dremel and have the right bit in it you can get away with using one, I do but I was once a serious power duck decoy carver and carved very fine detail with my Dremel and Fordom tools.
I use an 1/8" cylinder shaped diamond bit in my dremel when I relieve inlets. I use a skew chisel where I have room after cutting stop lines with the right sized gouge.
Here is one I did the other day, I used a dremel, forstner bit, skew chisel, riffler files, gouges and lots of soot. My lock wouldn't come close to going in the inlet and wouldn't cock after I got it in, it does now.