I bought a Mike Rock barrel blank with 5R rifling. I put it on a Rem 700 L.A. Now I want to turn it down to about the dimensions of the Rem. varmint barrels. It is only slightly smaller than the diameter of the original blank. My Gunsmith says I shouldn't do that. He says he will not guarantee the accuracy if I cut much steel off the diameter. Has anybody on this site ever lightened a Mike Rock Barrel? Was it detrimental to accuracy? Does it cause an increase in the inside diameter of the bore?