Model 19-4 Forcing Cone Issue

[Dmoconnell]

Hey, I am new to the site. I bought my Model 19-4 used from a police trade in

I have seen some posts on here about deposits on forcing cones/barrels.

I have what looks like a brass or copper spot on the forcing cone. The last time I shot it it was kicking out some significant debris when it was being fired. When I was in the booth over from my friend a piece of the debris actually hit my hand and caused some very minor bleeding.

Edit: I was using new republic 158 grain ammo. I am not sure if that is related but it was the cheapest factory brass ammo I could find.

Any idea what the issue is?

 

[series guy]

Brass is softer than steel so just flake that piece of brass off. Clean the gun thoroughly and try some name brand ammo.

 

[TJm15.38]

I would change ammo and shoot again.

 

[Alk8944]

It looks like the forcing cone needs to be reamed slightly larger. It doesn't look to have much interior taper to it. I have done other S&W revolvers that stripped bullet jackets because of this. Any competent gunsmith should be able to do this for you, or the tools can be bought from Brownell's to do it yourself. Besides the reamer you will need the gauge to be sure you don't go too deep.

 

[Dvus]

All good advise here. I agree with both solutions looking at the pictures. Try some Federal, Winchester, Remington or other name brand ammo first. If that doesn't eliminate the issue, A light reaming of the forcing cone would be my next step. You may also have a smith check your chamber alignment with the barrel. It's not an unheard of thing to find guns from large departments that have had cylinders or other parts swapped from other like guns.

 

[stansdds]

As others have stated, try different ammo first. If the problem continues, then the first thing to do is to have the cylinder timing checked. If it is off just a little, you will get bullet shaving. If the cylinder timing is correct, then a very light recutting of the forcing cone should fix the issue. I say very light because there is not a whole lot of steel at the bottom of the barrel shank.

 

[glenwolde]

There's a standard list of things you can check on a revolver.

Proper way to check a Revolver prior to purchase

There can be a few reasons for that problem, often more than just one. I'd bet the gap is excessive (the distance between the face of the cylinder and the end of the barrel) and/or there's significant end-shake (fore-and-aft play in the cylinder). You can check the gap with a feeler gauge.

The reason I suspect the gap is because it just about has to be excessive to let a piece large enough to go the distance you say it did to escape.

 

[steelslaver]

I would check the cylinder and yoke for play and alignment. A bullet striking high up is probably not rotational timing and lock up.

I do agree that the forcing cone looks kind of on the tight side though,

A fair sized shard of copper can pop out of a .006 gap with 35,000psi behind it. How do I know this you ask. A personal experience

 

[SGT ROCK 11B]

The last time I shot it it was kicking out some significant debris when it was being fired. When I was in the booth over from my friend a piece of the debris actually hit my hand and caused some very minor bleeding.

Any idea what the issue is?

Timing is off and it is shaving brass/lead from the bullet.

 

[taz666]

Could be that the ammo is just ****. Maybe a fragment was shaved as the bullet left the case and got blown out with the powder.

 

[Dvus]

Large chunks of jacket can leave a .003 b/c gap with no endshake. I speak from first hand (and face) experience.