Back about 1980 when I was involved with metallic silhouette ,M29s like mine had a habit of shaving bits of metal from the bullet.They redesigned the forcing cone and I had mine redone which solved the problem.

I realize the purpose of the "forcing cone" in a pistol barrel is to funnel a bullet down the barrel after it has jumped from the cylinder. But as I understand it, if the forcing cone is too large (however big is too large) then the pistol's accuracy goes to hell.

My question is, if you get a pistol with an oversize forcing cone, what can you do about it? Shoot oversized bullets? What does a guy do about this issue?

Several people have complained about cylinder throats in Ruger revolvers that were too small thus causing the forcing cone/bbl diameter to be too large for best accuracy. The solution was to open up the cylinder throats, and shoot cast bullets of proper fit to the bbl.
One of the main advantages of the Freedom Arms revolvers is that they are built "right".

NE, I hadn[t thought of a cone being TOO SMALL. That would be a problem.

I don't think the forcing cone being on the tight side will create much havoc. Reason I say this is; that for experimental purposes only (don't try this at home) Jim Taylor and I put a .45 Colt cylinder in my .44 Ruger Bisley and fired five rounds into one tight group at 25 yards. Swaging the bullets down from .452" to .430" did not seem to adversely affect the accuracy.

By the same token, firing a .44 cylinder from a .45 Colt revolver gave us a group of about 2.5" at 25 yards. This is as good as some of the groups I've seen shot from a revolver having the proper cylinder installed.

Much of the improvements I've seen regarding forcing cones is to ream the throat to 11� to improve alignment when the bullet enters the barrel. Most, if not all, of the damage I've heard of with forcing cones has been on the Fredaom Arms revolvers and horribly overdriving bullets in the .454 Casull. This is the reason Freedom Arms offers the forcing cone replacement option on the .454 chambered revolvers.

I have seen Ruger Super Blackhawks that would not shoot accurately enough for silhouette competition until cast bullets sized to .432" were used. The revolvers would shoot sccurately enough for plinking and most likley "minute of deer" out to 100 yards, but not to the level needed.

MS Hit, I feel better after reading of your testing. How much lead splatter did you notice from the undersized forcing cones with 45/44?

Shooting oversized bullets wouldn't really be a problem if the cone were a bit too big. I just want to know that will solve the issue.

The forcing cone is meant to direct a misaligned bullet into the rifling. I think Ruger uses an 18* forcing cone. The old colts had virtually no forcing cone to speak of.

Forcing cones do not come in sizes but are measured in terms of degree.
Forcing cones and throats are different things and should no be confused with each other.


I seriously doubt a forcing cone with to great of a degree would cause any measurable difference in accuracy.
Proper alignment with cylinder and barrel, throat size, tight spots in the bore, and ammunition (including bullet size) would all play a much bigger part in accuracy or lack thereof.

MS Hitman,
That is some pretty cool results with the 45 cylinder in the 44. How hard of an alloy were yall using? Pure lead or non-hardened WW?



David

If the cone is too large, the barrel can be set back a few threads and then the cone can be recut. This is a job for a gunsmith.

What makes you think the forcing cone is too big? What problem are you experiencing?

I suppose that if your forcing cone was too long it could lead to excessive gas blow-by and cause leading in your barrel which would decrease your accuracy.
If that is the problem using a bullet that is oversize might help, but might not "cure" the problem all together. You could still have lower than optimal velocities due to gas escaping and the gas blow-by may only be reduced, not eliminated.

A sure fix is to rebarrel or set that barrel back and cut a new forcing cone as was already suggested by Mountaingun.

David

This will not make it smaller but will tell you if it is the proper size "Barrel Chamfering Plug Gauge" Available from www.brownells.com

If you need to rechamfer your barrel throat they sell a "Complete .38-.45 Chamfering Kit".

If it is to big the barrel will need to be removed and cutback a thread or two then the forcing cone refaced and recut.

Thanks one and all for the wealth of information on my topic. I now feel I'm just about a "forcing cone" expert.

No splatter to speak of, and the bullets were just run of the mill wheelweights and commercial cast bullets. Nothing fancy at all.

One of the things that really impressed me was how well the cylinders matched up on different revolvers.

We just fired a cylinder full for that demonstration. No leading problems in my barrel. Jim told me he has done this on numerous occassions and experienced no problems of any sort.