forcing cones

[tomahawk223]

I have three S&W .45 acp revolvers, all were purchased brand new and are of modern lock type guns. My question is about the depth of the forcing cones.
They are all very rough looking, nothing like my old smiths. I wanted to clean them up with my 11 degree cutter but all of them fail the plug test with my .45 acp plug. I cant believe the factory sent these out failing the plug test. even my kuhnhausen 5th edition describes how deep it should be. Does Smith have a new standard for cutting cones? my reason to clean up the cones is leading as I shoot swaged Zero bullets and my 625 pc shoots to the right consistently. that forcing cone is the worst out of the three. how deep is really too deep.

thanks

 

[Narragansett]

I think you might be better off posting this in " Smith and Wesson Smithing Forum"

Oh, and welcome from RI

 

[Mike in Reedley]

I had the same issue with a 625 I bought about 15+ years ago. It too had a rough forcing cone, was at the max for depth according to the plug gauge and was horribly inaccurate. I was going to have to send it back anyway, so I cut the forcing cone even deeper, until it cleaned up. Afterwards it shot wonderfully. Still have it and it still shoots great.

 

[BLUEDOT37]

tomahawk223, which model 45ACP revolvers are they & how deep are the plug gages going past the opening?

The .020" over on the FC opening (.472") is fine to try & stay with but if you go over it's not the end of the world, IMO.

If you can get the 11 degree cutter to remove most to the roughness you want, without going too wide on the FC mouth, you may be surprised with the results.

That said even if you get the FC smooth there's no guarantee you still won't have leading issues. That's the way it went for me & I decided to stop using lead bullets & just go with plated or jacketed.

On .357 revolvers I've found the 5 degree FC cutter works great on removing FC roughness while minimally changing the FC mouth opening.

.

 

[Biggfoot44]

Considering that Taylor Throating is a semi- popular modification , that many people swear by , I wouldn't be too concerned about how deep ( ie how far down the bbl ) .

 

[Toolguy]

Ideally, the forcing cone (11 degree) should go in about 1/8" from the back in a given caliber. A little more does not seem to have any adverse effects. A smooth, centered forcing cone is much better than one with problems.
Leading can also be caused by a barrel constriction just ahead of the forcing cone.

The shooting to the right issue sounds more like a bad muzzle crown. If you recut both ends of the barrel, you will usually end up with a much better shooting gun.