Can a cylinder be bulged?

[TominCA]

I have an older 438 its 38 special - the steel one!. In good condition except one chamber extracts about 3/8 inch and then the fired case can't go any further. I have to push it out with a stick. The gun just started doing this. There was no stuck bullet event.

I cleaned it good and inspected the bad chamber as best I can with a bore light - everything seems fine. No evidence of cracking and if there is a bulge it is only a few thousandths.

Any body else have a similar experience? Any information or opinion appreciated.
Thanks

 

[Pisgah]

Unfortunately, a chamber can be bulged by a hot load. I have no way to diagnose your gun but I'd say a bulged chamber is at least a possibility.

 

[austintexas]

bulged cylinder

Yep, In '64, I had been reloading for about 3 years and I accidentally double charged a 38 special. Ended up with 7 grains of bullseye under a 158 grain bullet. We were shooting rocks in a quarry and It was a surprise when it went off. Luckily I was shooting it out of my M-19. The primer had melted and flowed down along the firing pin channel. case bulged and had to be driven out with a wooden dowel. Had to open the cylinder with a rubber mallet, it sheared the primer brass in the firing pin channel. It slightly bulge the cylinder. Since then I've had to shoot Nickel brass otherwise regular brass is a pain to eject.
SWCA 892
PS, It was my only double charge I have ever done.

 

[steelslaver]

If it is bulged you should be able to detect it. Mark the chamber, then measure the cylinder's diameter at the rear , the middle of chamber and the front at that chamber. Do the same using a complete different chamber.

You could also coat the inside of the chamber with Prussian blue, then insert a fired case from another chamber and remove it. The blue would remain heavy at the bulge

It wouldn't take much of a bulge, but under the right conditions it might be detectable looking through it as a shadow by the eye.

J frame 38 cylinders are easy to come by

 

[murphydog]

The model 438 has an alloy frame with a steel barrel and cylinder.

You didn't mention what type of ammunition you used when the problem started?

Since this gun falls under the Lifetime Warranty program, if you used factory ammo in it I'd return it to S & W and let them diagnose the problem. If the cylinder is bad they 'should' replace it for free.

 

[glenwolde]

I've seen a couple but it's odd to me that the case can move 3/8 of an inch before hanging. Usually the case expands into the bulge and won't move at all.

 

[stansdds]

Welcome to the S&W Forums. First, make sure the chambers are completely clean. Powder, lead, bullet lubricant residue can make extraction difficult. If it's all clean, make sure the issue occurs only with one chamber. If it occurs randomly with different chambers, then it's likely your ammo that is the problem. If it is just one chamber that does not allow smooth extraction, it could be bulged or it could be poor machining.

 

[Old_Cop]

I bought a M29 with a bad chamber. I brought it to the factory and had it replaced. Also had a K frame with a buldged chamber and moved it down the road. Thats 50 years age now!

 

[chief38]

I too would be interested in what ammo was being shot at the time you first discovered the bulge. If the bullets you were shooting were normal factory ammo I see no reason for S&W not to repair or replace it. I doubt they would do that though if you were shooting hand loads.

 

[Sgt. Buzzard]

I've seen that and it was reloader related.

 

[2152hq]

Just place a straight edge/steel ruler length wise accross the cylinder of the suspect bulged chamber. Hold it up to the light.
It'll tell you in an instant if it's bulged or not.

Last one I had for repair was a M36. A chamber was bulged enough that the hump just barely touched the underside of the topstrap as the cylinder revolved.
It caused a very slight hitch in the action but noticable. Plus the high spot had bluing worn off slightly.

Check the rest of the gun for deformation/mis-alaignment,,the frame, crane, etc.

 

[TominCA]

First, thanks to all for taking the time to reply to my post.

It is the cylinder. I used a straight edge to see the bulge. From measuring the case it looks like it is out about 5/1000 beginning where the bullet base seats in the case (approx) and runs for about 3/8" down the chamber.

 

[TominCA]

Must have been my reloads

The cartridges were reloads. 148 DEWC over 2.8 BE or 158 SWC over 3.5 BE. One must have been a double load.

I've ordered a cylinder assembly on ebay and I'll let you know how that goes when I try to install it.

 

[TominCA]

The cylinder replacement went down in flames! I ordered a 438 cylinder on ebay for about $35. It came and it looks like it had never been fired. Beautiful condition! But it didn't fit - The new cylinder was much too long.

I checked it against my newer 642 and it is the same size - I did not try, but it looks like a drop in fit.

I checked a few other Smith snubbys and there was a lot of difference in cylinder OAL.

At this point I don't feel like searching for a unicorn cylinder and will shelve the project for a while.

Thanks again for all of your help and suggestions!

 

[TominCA]

I got back on ebay and one of the vendors had a picture of a mod 36 cylinder with calipers on it - The exact right size - It was 30 some odd dollars so I ordered it.

Success! I used the original star (extractor) and with a few swipes of a diamond file it dropped right in! I ran my range rod down the cylinder
and the lockup was in the right spot.

I'll take it to the range later this week if I have time.

Thanks to everyone for all of your help and suggestions!