Thoughts on what is causing this

[martyd]

This revolver is a Model 57 no dash.

It is obvious the gun has been reblued.

There is a punch mark above the barrel pin, does not show up in these photos. I guess they removed the barrel for the reblue or they replaced the barrel which was originally on the revolver.

I shoot cast bullets, 15 BHN.

A photo shows what I think is leading on the exterior of the cylinder. It is very difficult to remove without using something abrasive.

Another photo shows the inside of the barrel throat with rings cut into the throat.

Another photo shows the usual leading / powder gas on the top strap above the barrel.

I used a Craftsman Feeler gauge to check the cylinder / barrel gap.

I could get a .009 to go all the way through starting on the right side. I could get a .010 to start on the right side but not go through. I could NOT get the .010 to start on the left side.

A .006 went all the way through with little effort then the .007, .008 & .009 took effort to get to go through.

I have a Mod. 58 and do not have the leading on the cylinder nor the rings inside the barrel throat. A .007 goes through with out effort while a .008 does not go through at all.

 

[martyd]

I forgot to mention I sent an email to Smith asking them what barrel length shipped with the revolver from the factory.

 

[austintexas]

That looks like throat erosion from my old eyes
SWCA 892

 

[Protocall_Design]

There is a small amount of erosion where the square edge of the forcing cone hole is rounded over with a very small radius. The rings and other marks are from a poor job of cutting the metal. That forcing cone needs to be recut and smoothed out. You want to check the chamber to barrel alignment, also.

Some of the leading could be due to the lead being too soft, and/or not the right bullet lube. The lube you have to heat up to get on the bullet is too hard for handgun shooting. If you dig some fired bullets out of the berm and they still have the lube on them, it's the wrong lube. If it doesn't melt off in the barrel, it may as well not even be there. Most of the commercial casters that do lubed lead use the hard kind because if they used the softer, handgun kind, then the bullets and lube would be one solid, unusable ball once they arrived at their destination. You might want to look into polymer coated bullets for the future.

 

[ralph7]

Hard to say if there is any erosion until you do an intense cleaning and lead removal.
Lead buildup is deceiving and hides as well as looking like damage that isn't there.

 

[Hair Trigger]

The cone is definitely eroded, compare the inner edge to this image, which is my M57 from 1968. The inner edge of mine feels sharp when you run a finger over it, and the inside surface is smooth all the way to the rifling. I've had this revolver for over three years, and shoot 210 JHP's and plated bullets through it regularly. Pardon the powder residue flecks on it, I haven't cleaned this one since the last range trip.

Your barrel-to-cylinder gap is also too wide, IMO. Mine is a very tight 0.004", it took up all the end play in the cylinder to get the gauge in, and it was still snug. The gauge fit the same way from the other side, indicating an even gap.

 

[Hair Trigger]

I forgot to mention I sent an email to Smith asking them what barrel length shipped with the revolver from the factory.

You'd probably have to get a letter from SWHF to determine that.

 

[martyd]

I got a response to my email to Smith requesting original barrel length.

Due to the age of the revolver it is not in their system.

So I guess a letter would be the only way to find out. I am not that interested in what the original barrel length was because it really does not matter.

I will look for someone locally who does barrel work on Smith Revolvers.

 

[biblethumpincop]

Frank Glenn is in Phoenix and is a master revolver smith. He worked on two of my Colts when I lived there.

Frank Glenn-Glenn Custom Complete Gunsmithing Service Glendale AZ