Forcing cone

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If you open the cylinder of any gun and look forward at the back end of the barrel, that is where the forcing cone is. It's a smooth countersunk taper or cone machined into the barrel end to "force", or to guide, or to align the bullet into the lands and grooves of the rifling and send the bullet on it's way down the barrel. Shine a light at the forcing cone and you can see the smooth area before the rifling, that's the forcing cone. Hope that helps.
 
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If you open the cylinder of any gun and look forward at the back end of the barrel, that is where the forcing cone is. It's a smooth countersunk taper or cone machined into the barrel end to "force", or to guide, or to align the bullet into the lands and grooves of the rifling and send the bullet on it's way down the barrel. Shine a light at the forcing cone and you can see the smooth area before the rifling, that's the forcing cone. Hope that helps.

perfect explanation....good job.
 
Nice video, but he forgot the most critical part.

The forcing cone is a very misunderstood part of the revolver barrel and even many professional gunsmiths don't really understand them.

THE critical dimension of a forcing cone is not the depth or angle of the cone, it's the diameter of the MOUTH of the forcing cone.
That outer mouth dimension is critical.
Too small and the revolver will be inaccurate and may spit bullet metal.
Too big and accuracy suffers.

An important part of cutting or re-cutting a forcing cone is to use the special drop-in plug gauge.
This precision gauge gauges the the outer diameter of the cone and makes sure it's not too big or too small.
The difference between too big and too small is tiny and you can't eyeball it.
Just cutting a cone blind without using the gauge is what often causes a revolver to suddenly loose accuracy.

This is what many people don't know, so they just cut cones blind.

BARREL CHAMFERING PLUG GAUGES - Brownells
 
Forcing cone? Right behind the ice cream cone..........sorry. Couldn't resist.
 
Picture--this is a S&W M29 in 44 Magnum --not that it
matters --they should all look the same. Pete


standard.jpg
 
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What is the factory spec for chamfering angle on a forcing cone for a Smith and Wesson model 28 .357?
 
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Not all S&W hand ejectors have forcing cones. There was a period of time when they were built without forcing cones. I don't recall the dates, but it has been discussed on here before.
 
My old 19 forcing cone is about .0035 and shoots amazing!my brand new 617 , first time at shooting club, a guy about 6 feet to left of me was getting hit with powder and junk.This is a $700 22 revolver took it home, forcing cone was huge compare to old 19. Back to Smith it goes. I pray they get it back fixed and soon. Ps my brother bought one also to go w his 29, his is a lot tighter. Also back of my cone had machining marks, like tool bit should have been changed. Maybe time to tighten up quality inspections. I was a machinest years ago, our inspectors were tough. T. Y. Any thoughts. This is Bumps 63
 
My thoughts are, someone without gunsmithing or machinist training should not attempt this. I am very comfortable working with S&W revolvers and 1911's, but I'm not sure I would attempt this. Maybe 10 or more years ago when I had better vision and steadier nerves. I'd pay the gunsmith to do it properly.
 
My old 19 forcing cone is about .0035 and shoots amazing!my brand new 617 , first time at shooting club, a guy about 6 feet to left of me was getting hit with powder and junk.This is a $700 22 revolver took it home, forcing cone was huge compare to old 19. Back to Smith it goes. I pray they get it back fixed and soon. Ps my brother bought one also to go w his 29, his is a lot tighter. Also back of my cone had machining marks, like tool bit should have been changed. Maybe time to tighten up quality inspections. I was a machinest years ago, our inspectors were tough. T. Y. Any thoughts. This is Bumps 63

I assume you are referring to the gap between the back end of the forcing cone and the front of the cylinder? If the forcing cone itself was "huge" compared to your 19, you do have a serious problem.
 

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