Update on the Model 36...Bad news

[bluegrass1945]

Howdy everyone, this is a follow up to my post from the other day about my issue with casings getting stuck in my recently acquired Model 36 from the 70s.
I determined that it is just one cylinder bore that is having issues. I tried 5 or 6 different types of ammunition through the one bore, and had the same result of a stuck shell every time. I cleaned the bore vigorously with a brush and Hoppe's gun cleaner to no avail. The scariest thing is that on my last attempt before giving up, I punched out the spent shell casing to find that the shell casing had split near the middle of the brass! Needless to say, I stopped shooting it immediately. So, it looks like my only option is a new cylinder. Am I correct in this? Also, were would be the best outlets to purchase this?
Thanks!

 

[mckenney99]

The good news is that there is an add posted today in the Marketplace for a couple of M36 parts kits. Take a look.

 

[bobsguns]

I would have another person or three inspect the gun before I bought extra parts. Nothing wrong with extra eyes on a problem, IMO.

My .O2

 

[cmj8591]

Take it to someone who knows what they are doing and have them check head space and end shake. I think your problem can be fixed without changing the cylinder.

 

[stansdds]

Definitely time to have a qualified gunsmith check it out. The gunsmith might also want to see the brass that was fired in the bad chamber.

 

[Bullet Bob]

If you do take it to someone (good advice), take some of the ammo you were using with you, separate from the gun of course.

 

[dsf]

Every Gun Part may have what you need. I've bought from them and after taking what I needed put what was left on EBay or GB. And GB has plenty of parts & parts kits sellers too.

 

[benf1]

Excuse my very limited knowledge, but if it's just the one tight chamber couldn't a qualified gunsmith bore out the chamber?

 

[M29since14]

BenF1, it’s possible the chamber has a slight bulge, rather than being “tight.”

 

[dben002]

might try running a rolled up piece of 800/1000 grit sandpaper through the cyl to knock down any high spots.....just a thought

if this is a bad idea I am sure someone here will tell us.....

 

[Shotguncoach]

BenF1, it’s possible the chamber has a slight bulge, rather than being “tight.”

I agree....a tight chamber won't split brass. I think you have one chamber that is shaped like a coke bottle. Are there scrape marks on the brass that comes out of that chamber? Like it was being resized on the way out?

 

[cmj8591]

Case head separation happens because of excess headspace, which is the distance between where the cartridge stops it's entry into the chamber and the point on the frame where the cartridge stops its rearward movement. Oversized chambers do not generally case headspace problems.

An oversize chamber will create a longitudinal crack like this one. From the way you describe the problem it sounds like the gun has headspace issues. Those can be easily corrected on a S&W revolver unless it has been cobbled to death. The other thing is that I am assuming that the ammo you are using is good and within spec. Brass separation can be caused by ammo issues, especially brass that has been stretched and loaded a lot of times. Do not, under any circumstances, try and enlarge or polish out any perceived imperfections in the chamber. Unless you really know what you are doing you will only ruin the cylinder if it isn't already. The fact that you are asking questions here is great but it also indicates that you might not have the skills to tackle this problem. Headspace in a S&W revolver is dependent on the relationship between the cylinder, yoke, frame and extractor. It is easily fixed by someone with the proper skills.

 

[bluegrass1945]

Thanks to all who have shared input. To answer a few questions; Yes, when I punch out the spent casings from the affected cylinder bore, they have scrape marks on them. And the crack in the casing happened vertically. I will attached a photo.

 

[cmj8591]

Thanks to all who have shared input. To answer a few questions; Yes, when I punch out the spent casings from the affected cylinder bore, they have scrape marks on them. And the crack in the casing happened vertically. I will attached a photo.

Looking at that photo I'm starting to lean towards the ammo. Try some new factory loads, not +p, and see what happens. That case looks a little tired to me.

 

[bluegrass1945]

I tried 5-6 different types of ammo, from several different manufacturers. The casing got stuck every time. This was the only one that cracked, so that might have been an isolated issue, but every casing, regardless of brand etc, got stuck. The overall problem is not an ammunition issue (although it could have been for the one that cracked), because the casing gets stuck every time, regardless of brand, grain, etc.

 

[Muley Gil]

I tried 5-6 different types of ammo, from several different manufacturers. The casing got stuck every time. This was the only one that cracked, so that might have been an isolated issue, but every casing, regardless of brand etc, got stuck. The overall problem is not an ammunition issue (although it could have been for the one that cracked), because the casing gets stuck every time, regardless of brand, grain, etc.

Sounds like you need a new cylinder or a good used one.

 

[oldcrotchety]

Based on your verticle split photo and description of stuck casings in a single chamber, you are definitely dealing with a bulged cylinder. Time to find a replacement cylinder.

 

[SGT ROCK 11B]

50 year old Model 36 with a problem.

That is a predicament, and I wonder if it was a lemon from the factory or bad reloads over the years.

 

[BC38]

Based on your verticle split photo and description of stuck casings in a single chamber, you are definitely dealing with a bulged cylinder. Time to find a replacement cylinder.

I'd bet my next SS check you're 100% right on this one.

I bought a 15-5 a few years ago that had the exact same symptoms - stuck cases in one chamber with a slight longitudinal crack right in the middle of the cases.

VERY careful examination revealed that the cylinder had one chamber that was "stretched" or bulged. The bulge started right at the cylinder stop-notch and ran about 2/3 the length of the cylinder - almost to the start of the throat.

Almost certainly due to someone shooting a really HOT reload that just almost-but-not-quite ruptured the cylinder.

A replacement cylinder was the solution.

Here are some photos of what I found upon very close inspection under bright lights. The "stretch marks" are outlined in red.

 

[steelslaver]

Use a good set of calibers or better yet a 2" mic to measure the diameter of your cylinder in several spots. I bet the bulged cylinder gives a higher reading, You could also close the cylinder, then stick enough feeler gauges over the top of a good chamber to get some drag sliding them around over cylinder and then rotate the "bad" cylinder to the top and see if the gauges get sticky. The material in the bulge had to go out because if it went sideways one of the chambers beside it would get tight, Cylinders are available. I have several extra model 36 cylinders but I will not be home for another 3 to 4 weeks.

I have usually more problems with fitting end shake than carry up (timing) fitting a different cylinder. Either to much and need shims or none and need to trim the yoke tube. J frame shims are smaller than the ones used in K,L,N frames by the way