Overcharge Damage

[chopperman]

I overcharged a target load and damaged my cylinder and blew the rear sight off my 14-4. The cylinder has a hole where the cylinder latch notch is, it must be the weakest area of the cylinder. That hole and the rear sight are the only damage I can see on the gun. Could it be repaired if I could find a cylinder and rear sight for it.
Stan

 

[Sevens]

I'm trying to imagine a scenario where a blown cylinder damages a rear sight and yet somehow, the top strap is entirely unaffected.

I suppose you could attempt to stick another cylinder in there, but it seems foolhardy to me.

What was the intended load and what was the actual load?

Have you gotten to the bottom of HOW you ended up accidentally overcharging the case?

 

[moosedog]

I'm glad you didn't get hurt.
Just wondering, were you using a progressive loader or doing single stage?

 

[Hondo44]

I think a replacement cyl would work fine. But FIRST take some measurements with a caliper of the cyl window and compare to another Model 14 or 15 to verify yours is still within specs and the top strap is still straight. Also inspect the upper corners of the cyl window/top strap with magnification to verify there's no cracks.

The sight replacement may be more work to fix. I'm not surprised the rear sight took a hike. It's only held with one small screw at the front of the sight tang and the screw hole is just forward of the barrel/cyl gap! Then the sight would easily slide backwards out of the milled groove in front of the hammer.

Did the front screw head break off? Is the threaded portion still in the hole?

 

[s&wchad]

That is the thinnest and weakest spot on cylinders that hold an even number of cartridges. The stop notch is located between the chambers on cylinders that hold an odd number of cartridges (5 or 7).

I've never seen photos like that in over 15 years on the board or heard of a similar problem. Overpressure failures typically result in large chunks of the cylinder, sometimes including adjacent chambers, going airborn and taking the topstrap with it. People are not typically injured seriously when this this happens.

Brass is fairly stout that close to the case head. My guess is that there was a weak spot/breach in the case that just happened to align with the stop notch and the venting gasses did that damage at peak pressures. Pretty much a fluke and I suspect it was related to bad brass, rather than an overpressure load.

I have seen reloaded shotgun shells with a crack in the plastic near the base cause nasty flame cutting in the chamber, but shotgun barrels are usually very thick in that location and don't fail. This makes a good case for carefully inspecting you brass/hulls and discarding any that have show issues.

 

[chief38]

Personally I'd not even attempt to repair it! Use it as a pencil holder and get another Cylinder. Repairing it would be more trouble and expense than replacing it and I doubt it would ever be right anyway. Should be readily available - check the gun parts guys and ebay.

Nothing wrong with the barrel or cylinder pictured below - I just use a lot of pencils.

 

[glenwolde]

I assume you know it was an overcharge because of the report and recoil?

That is the oddest failure I've seen. I don't think it was the brass.
Just enough over-pressure to blow only the weakest spot?

 

[2152hq]

That blow out in the bottom of the lockng notch in the cylinder looks like awfully thin wall metal.

Perhaps the notch or notches were cut too deep to begin with.
It's not an unkn occurance.

Colt cut the notches too deep on quite a number of 3rd Gen SAA revolver cylinders and had them blow out in the same manner when used with factory ammo by their customers.
Some never made it through their Range.

The case wall is already thin there, so that isn't going to help contain too awful much pressure. A paper thin bottom wall to the locking notch is all that keeps the case from blowing out in that spot.

I'd check the frame for straightness and any damage (cracks,etc).

The old cylinder may go right back on if it's not buldged or damaged beyond the hole in it.
With that you can soon tell if something on the frame is bent.

If everything seems ok, try a new(er) cyl and see if that fits and go forward from there.

Junk the blown out cyl to pencil holder status as a 38spcl.
You might be able to use it as a smaller cal cylinder if you lined the chambers and very slightly recut that one bolt notch.
But that's only if you were in to building projects.
K frame 38 cylinders are pretty easy to find and inexpensive though.

 

[pharmer]

I have seen reloaded shotgun shells with a crack in the plastic near the base cause nasty flame cutting in the chamber, but shotgun barrels are usually very thick in that location and don't fail.

I had that happen a few months back with a factory loaded buckshot cartridge. Joe

 

[reddog81]

If serious about repairing I'd start taking a variety of measurements to see if the cylinder window is still square. Measure to to bottom and front to back in a couple different areas and see if anything is off. You might identify a problem quickly or maybe not.

Are the measurements of the blown charge hole the same as others? Throat, diameter of cylinder, diameter at flutes, etc?

I'm not a gunsmith but that's what I start looking at if it was mine.

 

[austintexas]

over charged

I remember in my early years reloading, I double charged a .38 special using bullseye. lucky for me the only 38 caliber revolver I owned at the time was my M-19. Didn't hurt the revolver but the primer flowed back in the firing pin hole and I had to use a rubber mallet to open the cylinder. A wooded dowel knocked the brass out of the cylinder. Happened in 1964, still have the M-19 and it still shoots.
SWCA 892

By the way, I have a .38 cylinder and crane that I'll never use. I'd pass it on for what I paid for it 25 years ago. Only thing is you would have a Pinto when you are done. It's nickel

 

[chopperman]

I have no way of knowing how much the overcharge was, but it could be a double. The actual load is 2.8 grs, of Tite Group with a 158 gr. bullet and a good roll crimp for Bullseye shooting. I loaded these on a Dillon 550B which I've loaded 10s of 1000s on before. I didn't have my light over the press the night I loaded these for practice.
Jim, the front screw head broke off, I'll have to get the other piece out. Strange thing is this strap was drilled and tapped for a scope rail mount. You can see where the pressure came up through the rear hole it was directly above the latch notch. There was brass vapor around that hole and area, so that probably saved the top strap from being damaged more seriously. I cleaned the window area and didn't see any cracks or damage, I'll measure tomorrow.
The recoil and report of this shot were about the same as the previous 64 shots of the 100 that I loaded.
Austintexas I'll keep you in mind, but I'll see if I can find a blued one first. Thank you for the offer.
Stan

 

[chopperman]

I forgot to ask if any K-frame cylinder and yoke will work for my model 14?
Thank you all for the help,
Stan

 

[austintexas]

k frame

I don't think the M-19s will fit, I think 357 is longer
SWCA 892

 

[ISCS Yoda]

Buy a new gun. Don't take chances.

 

[chopperman]

I don't think the M-19s will fit, I think 357 is longer
SWCA 892

Yes, I have seen a lot of K-frame cylinders w/ crane M-10 and some M-15s on E-Bay. Definitely 38 special models only, thanks first off is to make sure it's a safe in spec frame.
Stan

 

[BSA1]

I have seen this happen once only it was a Model 28 .357 cylinder reamed out to 45 Colt conversion. Gunsmith got a little sloppy with the reamer and when it was fired it blew a small hole in one of the notches. Fortunately the owner was only shooting standard pressure 45 Colt ammunition so no damage occurred to the gun.

 

[rosewood]

Personally I'd not even attempt to repair it! Use it as a pencil holder and get another Cylinder. :

I think that is what the OP said, he wanted to know if replacing the cylinder and site would be ok. Don't think he was discussing repairing the cylinder.

Rosewood

 

[steelslaver]

I tend to agree with Hondo that the frame may still be good. Measurements should tell the story. You could also get some dye penetrate from a welding supply and check the frame for cracks. Way it works if you spray on a thin dye then wipe the outside clean with a rag, then spray on some developer, If there is a crack the dye will seep into it and then bond with the developer showing a red line inn the white developer. The over load must have been just enough to blow out the notch and not completely take out the cylinder. K frame 38 cylinders are fairly easy to find and fit.

You just don't see blown up frames when the cylinder stays together. For an idea of the strength of a steel frame, scandium frames are the same dimensions as the steel ones. The best scandium alloys have a yield strength of 381MPa and a tensile strength of 467MPa while 4140 has a yield strength of 415MPa and a tensile strength of 655MPa. That is appox 9% less yield strength and almost 30% less yield strength. Yet S&W made a scandium 357 in the even smaller J frame.

People get all worried about putting a 357 cylinder in a K38 steel frame and yet S&W obviously trusts one in a smaller scandium frame. LOL Same goes for converting a steel N frames to larger calibers in view of the 329s being produced and fired regularly.

 

[teletech]

It's probably fine, but if you want additional piece of mind and address the doomsayers out there, one could check the frame for cracks. As Steelslaver says, there are kits to do just that. For those not experienced in checking for cracks, I'd detail-strip the gun and look for a sympathetic machine-shop to magnaflux it.
After that, popular online auction sites will have cylinders for you. Expect to spend $60-100 on average these days. If you don't have a lathe to make adjustments then you will need to get a cylinder of the same configuration in terms of gas-ring and such. Sometimes a cylinder will fit and sometimes it won't without smithing, but for a model 14 your odds are generally very good. The extractor is fit to the cylinder, so your odds of having a trouble-free transplant increase if you get a cylinder with it's extractor. Check your cylinder timing after the swap of course.