Cuttihg Threads For A Cone Comp

[San_Esteban]

A friend of mine wants to get an EGW Cone Comp and install it himself on his 5 inch Para barrel. He has a couple of questions. Should he have the threads cut by a machinist friend (very friendly price) or get the die and cut it himself? Also, how is the index accomplished? Set screw, pin or does the threading determine the index? OK, the questions are piling up. Is there a book or set of instructions for this work he can obtain? I did a search for this stuff, but the end answer is always “give it to your gunsmith.” Our local gunsmith says he can get at it in 6 months or so. Thanks for any direction on this.

Later, Steve

[L9X25]

Steve,

Have him take it to the machinist friend and the results will be much better. It is difficult to cut the threads perfectly square with a die, even using a bore guide. I have done it many times and messed up a few new barrels in the process.

You index the comp by removing metal from the rear of the comp face (that mates with the slide and that is best done on a lathe. The farthest the clearance can be out is .020" since that is the distance the comp travels with one full turn.

Hope that helps,

Leo

[San_Esteban]

Leo

Thanks, that answers the question. This is a great place, all the answers are here.

Later, Steve

[Flatland Shooter]

Depending on the barrel, you may also need to have it trimmed to fit. A 5" barrel usually works well with a cone comp, but if the comp uses a conversion cone, a 5.25" barrel may be needed.

Also, the bore of the comp will need to be aligned with the barrel and reamed to .008" over the bullet diameter. EGW comps are intentionally bored undersized to allow the gunsmith to accurately ream the comp out to get the most out of it.

Bill

p.s. And its getting tough to find a good barrel to comp alignment reamer. Mine disappeared in a move back to Texas and I'm having trouble finding a new one. Anyone with a 9mm reamer in good shape want to get rid of it?