Here is what I did.
Fire Lapping is taking a bullet either cast lead or plain copper jacketed and impregnating grit into the outside of the bullet. The grit comes in three sizes. The 220 is the coarsest with 320 in the middle and 600 being the finest. The kit comes with three little tubs of grit. (This grit is like what you use to grind engine valve seats with) and two pieces of hard steel bars. In practice you set one bar flat on the table and then using a popcicle stick you put a little of the coarsest grit on the steel bar. Then you lay the bullet in the grit and take the other steel bar and press hard and roll the bullet back and forth until it becomes sort a frosty looking. Which means the grit is stuck into the surface of the bullet.
Then you prepare your empty cases just like you were going to reload a round but only put in a small charge of fast burning powder. The idea is to just get the bullet out of the barrel not to do it super sonic. I use Red Dot shotgun powder, about 8 grs. of it. That will usually push even 175 gr bullets out the end of the barrel and you can see a little puff of smoke so you know the bullet exited.
Then after you run 20 bullets with the coarse grit on them you clean the barrel very good with solvent and keep cleaning until it comes up clean.
Then you start over with the 320 grit. 20 rounds of them. Again clean the barrel very well and then go to the fine grit. 600 grt
Again you shoot 10 to 20 of those bullets that are covered with the fine grit and you guessed it clean it again.
After all that try standard factory rounds and see what your groups look like. There will be a difference.
One thing you need to know first is that the barrel needs to be CLEAN before you do this fire lap business. And that is the hardest part expecially if you have a really pitted barrel like I started with.
One thing I found was after you clean the barrel really good, take it to the range and shoot 10 rds through it. It may well be you just had a badly fouled barrel and don't need the fire lap.
In my case it definately needed the fire lap.
So now you learned something new today. And that is what this club is all about.
Too Tall I'm glad you asked.
Sarge