I've been thinking about fire lapping the barrel of my 1892 Winchester .32-20 since I get some rounds that keyhole, especially with the factory ammo, and there is some pitting. I know I don't have a huge amount to gain, but maybe if I can get a little better accuracy out of it, I will be happy. I slugged the barrel, and I get .312" so I still have rifling left to work with. I see quite a few people recommending valve grinding compound, just wondering if someone who has used that method, how many bullets have you fired out the gun doing it that way?
Here's what one group looks like with my 115 grain handloads and .312" bullets.
This is at 25 yards, I would say the group is about 2 inches.
Now here it is with factory Remington 100 grain bullets. I don't know what size the bullets are with this ammo if they are a smaller diameter but they were going all over the place and keyholing all the way there. Same distance. Not one of them hit the target with me shooting from a rest.