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Wally
09-05-2008, 10:24 AM
Have been told that on revolvers that shoot CBs that one should have a FC cut to a 11° taper for the best accuracy. Brownells sells the tool cutter for $50 that works for calibers from .38 to .45--has anyone tried this? It is a bit daring to me to try it and I'd like to read about the experiences of others that have already tried it.

Wally

S.R.Custom
09-05-2008, 10:56 AM
This only works on a new barrel, or if you set the old barrel back... Factory forcing cones are typically cut at 18°, which is wider than the 11° of the Brownells tool. (In other words, you can't put back what already has been cut away.)

As for the efficacy of the 11° cone itself... well... it varies. In and of itself, I've not found it to enhance accuracy at all. What it does do is leave more meat at the barrel throat-- which is a good thing in the magnums. But that's about it.

In revolvers with mis-aligned chambers/bores, the 11° cone actually has to be cut deeper into the barrel than an 18° cone to yield the same throat diameter sufficient to 'capture' all of the bullet diameter as it transitions from the chamber to the bore. This deeper cone creates more freebore in the barrel throat, which in turn diminishes accuracy.

I've found the most accurate forcing cones are the 18° ones, cut no deeper/wider into the throat than is absolutely necessary to capture the bullet as it leaves the chamber. Of course, this assumes that any bore/chamber alignment maladies have been corrected first.

Char-Gar
10-17-2008, 03:33 PM
I have had one of the Brownell forcing cone (11 degree) cutters for over a dozen years and have recut the factory forcing cones on over 30 Smith and Wesson, Colt and Ruger handguns with 100% sucess. The long taper will clean up the factory cone, without resulting in a two step cone.

Follow the directions and don't remove any more metal than necessary to remove the factory cone. Lube, cut, clean, inspect and then relube the cutter and do it over again. Go slow, use the right size bushings and everything will be alright.

Done right, it will do no harm and often will improve the performance of the pistol.

anachronism
10-17-2008, 04:08 PM
Brownells also sells plug gauges for identifying how deep to cut your throat.

KCSO
11-04-2008, 10:54 AM
What I have found is that for Cast bullets smooth is more important than any specific angle. Most factory forcing cones are a little rough and some Uberti and Ruger forcing cones have annullar rings like a rotted tree stump. I made a set of brass laps and have used Brownell cutteres in both 18 and 11 degrees. i cut the rings out and then lap the forcing cones to shine like a mirror. This does wonders for shooting cast. if you then ream the cylinder mouths to a uniform dimension and use the right size bullet leadig will be a thng of the past.