Chasing the Lans

[halfmoanut]

I have heard this phrase and I think it means after shooting a certain amount of rounds because of the bullet pounding against the lans they receed,is there a rule of thumb after how many rounds must the bullet be moved out to keep in touch with the lans?

 

[Mikem]

I dont know of any 'rule of thumb', but your right, they do move out with erosion. I use a Stony Point tool to get my reading, to just touching the lands with all bullets I shoot, and record this info. Then recheck the measurements about every 250 to 300 rounds, and they will grow a little.
Mike.