Revolver forcing cone angle/reamer

[218bee]

I have heard of pistolsmiths changing the angle of a revolvers forcing cone (I think thats what you call the end of the barrel where boolit enters) for improved accuracy. I was wondering if anyone has tried this and was looking at Brownells but could not find a tool for a do it yourselfer. They do have cylinder chamber reamers and muzzle crown cutters. Maybe I did not look hard enough.
Anyway does anyone think this a benefit? Is a certain angle better than another. I shoot some pretty old revolvers and was thinking they might benefit from at least a "cleaning up" in this area. What ya think???

[Scrounger]

Looks to me like the barrel would have to be removed to work on the forcing cone. That would take it out of the evil clutches of most of us bubbas...

Shows how much I know...Wrong again.

[Bret4207]

Brownells sells a kit for just that. I'll see if I can locate it for you.

[Bret4207]

Here ya go- http://www.brownells.com/aspx/ns/store/catsearch.aspx?c=1306&p=4810 That's the critter IIRC.

[mtgrs737]

I have an interest in this area too, any of you guys have any experiance in this area?

[JMax]

I have done it many times BUT do not ream the forcing cone if if passes the no go gage. Then yo need to set the barrel back.

[lathesmith]

The forcing cone seems to be one of those neglected areas in revolver manufacture. I have polished more than a few of mine--I've had several guns of various makes that had SERIOUS burrs and ridges that shaved lead and definitely had improved performance with a good polishing. As JMax implies though, it is easy to over-do it, you don't usually have to remove much metal to clean things up.
lathesmith

[anachronism]

I do mine where needed. You do need to use the plug gauges to make certain you don't screw everything up. Early Redhawks had especially poor forcing cones, one of mine looked like it had been cut with a rat-tailed file. You"ll want to check your original forcing cone to make sure it can be recut to the angle you want. Different manufacturers use different angles.

[Larry Gibson]

I also have the Brownell's kit and have reamed numerous forcing cones on revolvers. As lathesmith mentions many just need a good polishing.

Larry Gibson

[SCIBUL]

+ 1 ! The only revolvers that didn't need it were my RUGER Blackhawk .357 and my S&W 629 DX.

[garandsrus]

I think that the forcing cone is reamed as a pull through reamer, so the barrel doesn't need to be removed.

John

[Ghugly]

I think that the forcing cone is reamed as a pull through reamer, so the barrel doesn't need to be removed.

John

Yep. I have the Brownells kit. My .44 Bulldog spit lead do to an almost non-existant forcing cone. 5 minutes with the reamer and no more lead spitting. Quick, easy, and does what it's ment to do. I can see, however, that it would be easy to over do.

[218bee]

Thanks guys I did find the kit after looking through my Brownells more thouroughly. Please tell me how to guage when to stop. I am not sure how to check.

[roger rabbit]

You need to get the forcing cone guage for the specific caliber of interest to go with the reamer.

[leftiye]

Side note, and if a Ruger rep is reading here I guess he'll just have to endure the bad press. I have a friend (Boom Boom) who just slobbers whenever he gets a new Ruger. He's brought a couple by to have chamber mouths, cylinder gap, and forcing cone checked out. How does .030" sound for a cylinder gap? What do you think of off center forcing cones? Or forcing cones that ahve a depth of 3/8" before the rifling starts (or both)? Everyone knows about how many Rugers have smaller chamber mouths than groove diameters. All of their strength, and design count for nothing to me if they're gonna have H&R quality control.

[Bret4207]

Side note, and if a Ruger rep is reading here I guess he'll just have to endure the bad press. I have a friend (Boom Boom) who just slobbers whenever he gets a new Ruger. He's brought a couple by to have chamber mouths, cylinder gap, and forcing cone checked out. How does .030" sound for a cylinder gap? What do you think of off center forcing cones? Or forcing cones that ahve a depth of 3/8" before the rifling starts (or both)? Everyone knows about how many Rugers have smaller chamber mouths than groove diameters. All of their strength, and design count for nothing to me if they're gonna have H&R quality control.

That's a factory "Taylor Throat"!!!:mrgreen:

[HeavyMetal]

The only time I've "cut" a forcing cone was after I set back a barrel. Because I shoot a lot of lead I kinda favor the 11 degree set up. Trying to re-cut a factory forcing cone, especially if you want to change the angle, is a bad idea. Basically to many compound angles and you'll only make things worse IMHO.

Polishing, while staying within the factory cone angle, is a different story. Find out which angle is used on the specific gun your trying to polish, Brownell's has them listed in the catalog, and use the finest grit compound you can find and a real light touch because this can be overdone as well!

[218bee]

Yeah I guess I'm more interested in "polishing" them then changing the angle. It looks like Brownells sells a "soft brass" cone shaped gizmo that you can imbed some polishing compound into it for polishing.

[S.R.Custom]

Polishing an existing forcing cone is a good thing, but if you have to re-cut it or modify it in such a manner as to correct spitting or accuracy problems, you have a chamber/bore misalignment or a timing problem that needs fixed.

[McLintock]

Just be sure to note that they have cutters with different angles, so be sure you're matching the right angle to the gun you're doing. Seems like Smith's like a 5 degree and Colts and Ruger single actions are usually done to a 11 degree.
McLintock

[Snapping Twig]

IIRC, S&W uses 18 degrees from the factory, at least on the 686 I sent in for a barrel repair.

I have all my revolvers recut to 11 degrees for lead. I've got a 586-1 recently aquired that shoots so well that I don't know if I'll be sending it off for the change. Tempting, but I'm going to wait a while.

[Ghugly]

Polishing an existing forcing cone is a good thing, but if you have to re-cut it or modify it in such a manner as to correct spitting or accuracy problems, you have a chamber/bore misalignment or a timing problem that needs fixed.

In my particular instance, I was correcting a factory defect. The start of the forcing cone was so small that a boolit sized to groove diameter (.430) could not be started into it as the front driving band was larger than the opening of the forcing cone. The lands extended all the way to the opening of the forcing cone. All I did was ream the cone until the front driving band could comfortably enter the opening. I should ream it even farther, as the opening of the forcing cone is still smaller than chamber diameter. I believe the timing and alignment is, at least, reasonable, as all lead spitting ceased and accuracy was improved. Of course, decent accuracy is difficult to achieve when you're trying to dodge the lead hitting you in the face.

[S.R.Custom]

In my particular instance, I was correcting a factory defect.... I should ream it even farther, as the opening of the forcing cone is still smaller than chamber diameter. I believe the timing and alignment is, at least, reasonable, as all lead spitting ceased and accuracy was improved.

Good show. Although the forcing cone should, as you say, be opened up to catch all of the chamber throat opening, and then some. How much more would be contingent upon the particular gun in question...

The forcing cone picture below is on a Ruger SBH I'm currently working on. I regard it as ideal for this gun, which has more or less perfect alignment and timing. I go a little deeper and wider on S&Ws, as they tend to not carry up as well after they have a few thousand rounds through them. Particularly if the shooter is left handed.

Revolvers have enough free-bore as it is, so I'm not a big fan of 11° forcing cones or, gasp, Taylor throats. In my mind, these are measures that merely treat the symptom, and do nothing to address the real issue. Defective forcing cones like yours not withstanding, I get much better results, accuracywise, by addressing the core problem. In the case of the SBH I'm working on now, there was a slight chamber/bore alignment problem that was easily fixed by "moving" the bolt hole a bit...

http://www.castboolits.gunloads.com/picture.php?albumid=70&pictureid=481

[cajun shooter]

The Rugers have used the 5 degree forcing cone since the early 80's. If a beginner trys to use one of the kits with the 11 degree tool, he will cut what is known as compound angle and have all kinds of problems. When shooting PPC in the 80's I would use the 11 degree tool on all of the pistol teams guns. This will stop the shaving and spitting of lead. The guy next to you will thank you. The tool kits by Brownell's are very good in the hands of a good armorer or smith.

[DJWright]

I've done several forcing cones at 11 degrees for cast bullets. Without exception every one shot 100% better after reaming. In the case of one S&W .44 spl. results were amazing. It does not matter what angle the factories use, an 11 degree will work fine with all of them for shooting cast. You just go very slowly by hand with lot's of oil. Takes about 3 minutes.

[Swede44mag]

Have you checked your cylinder throats for correct size if they are too small the gun will spit lead and accuracy will suffer.

I bought a Brownell kit for a S&W 10 shot .22 it was spitting lead real bad and accuracy was non-existent. After using the forcing cone reamer with the gage so I didn't go too far it still spit lead but not as bad. I used a range rod and found out that 3 of the 10 cylinder chambers did not line up correctly. I bought it used I could have sent it back to S&W for a repair but I sold it at the same gun show I bought it at and bought a DW .22 with a 10inch barrel (has a ram on it) the pistol didn't work as a double action. I found out it was made to shoot silhouette and bought the parts from Dan Wesson to make it double action. The bad part is I spent a lot more buying the S&W including trading than it would have cost out right to buy the Dan Wesson in the first place.

Good luck with your forcing cone reamer take it slow and use the right tools I am sure you can make it work.

BTW I have a scar on my left hand where a friends H&R .22 spit lead and took a chunk of hide out.