Hello Everyone!

It is my first post, so I would like to say hello to the users and apologize in advance for any language errors (I am from Poland).
I wrote it because while I am cleaning my 5-year-old S&W 686+ I have noticed a kind of burnt mark on the barrel. Do you think these could be signs of burnout of the forcing cone? This would be strange, because I put through approximately 2,000 rounds of 38 Spec and 1,000 rounds of 357 Mag. I thought the L-frame revolvers do not have problems with shooting 357 Mag like K-frame have. Does anyone have any exprience with using revolver with such problem?

Attached Images

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Welcome to the forum.

The erosion around the perimeter of the barrel extension is both normal, and inconsequential. Temperatures in this area during firing are incredibly high, and damage here is inevitable, unless the revolver sits on the shelf unused.

To help mitigate damage, keep the front face of the cylinder, the cylinder interior, and the barrel, including the forcing cone and face of the extension, as clean as possible. Regular maintenance is the best way to care for the gun, and prolong the life of the components. Regular cleaning and care will also help keep the specifications regarding the front and rear gauges in the cylinder assembly correct.

If wear and tear ever impact the revolver's barrel extension spec's to the point that accuracy or safety is affected, the barrel can be set back, and the extension and forcing cone area re-cut.

Ciesz się ramą L.

With proper care, your 686 will last a lifetime. (or two)


Carter

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Ret. LE, FA Instr, S&W Armorer

The condition of your revolver's forcing cone looks normal to me. I would not be concerned.

Looks normal to me.

Welcome to the forum! You've got one of S&W's greatest revolvers there. The 686 has been my favorite for 40 yrs now.

Your gun looks normal. No problem there at all. Enjoy it and hang around here on the forum with us with future updates on your 686.

That is erosion and it is from shooting full power 357 Magnum ammo, possibly loaded with bullets weighing less than 140 grains. I would not worry about it, the barrel extension/forcing cone on the L-frame is full diameter and thick. It was made this way to withstand the wear effects of the 357 Magnum cartridge.

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VCDL, GOA, NRA

Looks fine to me. Just keep her clean.

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213th FBINA

Here was my 586s forcing cone before I traded it off

Eldottore, I think your force cone looks ok. Just make sure it's not lead. Give it a good clean.
Lead can build up in some places.
If it's not lead, it still looks fine. I've shot my Revolvers far far worse than that.

That is significant erosion and is why the L-frame has not only a thicker barrel shank than the K-frame, but no flat spot on the shank for crane and gas ring clearance.

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VCDL, GOA, NRA

Thank you for all your replies. I feel all my concerns fade away. In Poland, knowledge how revolvers works and how repairing them is low, even among gunsmiths.
The 357 ammunition is standard FMJ 158 grs, I have never used hot loads.