Valve grinding compound

Re: Valve grinding compound

Valve grinding compound will screw your barrel for good. Just use it to lap rings, lugs. Don't put it in the barrel. On thed other side, if your tring to use JB Bore paste to lap in rings
its going to take a while
 
Re: Valve grinding compound

Valve lapping compound contains a harder cutting material than JB, which IIRC Aluminum oxide/Alumina and supposedly does not imbed into the steel. The harder abrasives like silicon carbide can imbed themselves into the steel, and must be carefully removed.

I know of a least one custom barrel maker who uses a fine grit valve lapping compound to lap the blanks prior to rifling...
 
Re: Valve grinding compound

I have used valve grinding compound to recrown a barrel and it worked perfectly. It took a while though. I chucked a carriage bolt in my drill and used the head of the carriage bolt. Make SURE you plug the barrel with paper towel or tp at the muzzle to keep the valve grinding compund out of the bore. Once you are finished, spray degreaser from the chamber end to get any compound that may have gotten into the bore. The clean the muzzle carefully.
 
Re: Valve grinding compound

KM7, the method you described is pretty much exactly what a very reputable gunsmith hass recommended to me. he siad to use a 5/16 brass round head wood screw. keep a agnifying glass handy to closely look at your progress and to make sure you finsh with a 360 degree perfect ring around the muzzle
 
Re: Valve grinding compound

I did the brass screw and used the 400grit compound from a fire lapping kit on a horrible looking crown that had chatter marks and was giving horrible accuracy. It actually goes pretty quick and the results were very impressive.

JB or Fitz will take a long time unless your just trying to lightly polish it.