I have been loading mild 38 special target loads for my 686 6" barrel and have been getting several split cases (on the side not the mouth). Cases are once fired mixed brass. Load is 4.2 g of Unique with 158g LSWC. Any advice?

It happens........

Could be defective brass to even a bad cylinder fit.
I even had the top half of a case separate from the bottom half.

If new factory ammo you may call the company and see if there
has been any recalls on that lot of ammo.

Safe shooting.

How many times have the cases been reloaded? All brass will work harden (get brittle) and split after several reloadings, some brands will last longer than others, but I have lost count on some .38 Special brass after 10 times through the process. If factory ammo shoots fine, reload some truly once fired and see if splits happen on second or third reload. Also check to see if all the split cases have the same headstamp. Could be (prolly) you just got some "bad" cases.....

Sounds like the cases are not truely once fired

I usually get those splits after several reloadings. 4.2 grains of Unique is a standard pressure load, not powder-puff light but not heavy. I would get at least 10 reloadings with 5.0 grains unique.
Either that brass is not "once" fired, a chamber or two is on the maximum side of tolerance with sizing die on the minimum (thus overworking the brass), or the brass is of poor quality.
Something I have noticed is I get less sizing with my old steel dies than with the new carbide sizing die I bought. My old ones didn't work the brass as much as the new carbide ones and the brass lasts longer.
Are you using carbide sizer?
Gary

Advice? Buy some new brass. Several possibilities. Loaded excessively (too many times) and brass is simply fatigued. Excessive sizing with a carbide sizer as gwpercle mentioned. Or you have polished the brass with a polish containing Ammonia such as Brasso. This causes Nitrogen embrittlement of brass and premature failure. Regardless, the solution is buy new brass and start over.

With good quality brass, and dies that do not size any more than needed, you should get from 12-20 loads from a case. And then the failures will usually start as case mouth cracks. Nickle cases may not give quite as many loads as plain un-plated brass.

You can use the Redding Dual Ring Carbide die: Dual Ring Carbide Dies - Redding Reloading Equipment: reloading equipment for rifles, handguns, pistols, revolvers and SAECO bullet casting equipment Or simply neck size with the usual carbide sizer die and finish sizing the body with the Lee Carbide Factory Crimp die in a separate step. should be easy in a progressive, or just an additional step on a single stage press.

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I was gonna say "Split Happens"...

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In my experience, splits occur most with nickel plated cases. You didn't say, but are your cases nickel? I have started pitching mine so that I only reload brass now, and no more splits.

It's kind of hard to were low pressure brass out. Used to shoot tons of 38spl's & 45acp's with a cast bullet/nra 50-50 lube combo. Had sooooooo much brass I'd put it in 5-gallon buckets and clean & reload it all winter for next year.

The longer the brass sat, the harder it was to tumble/clean. Used brasso all the time to help clean them up quicker. Never had a problem with brasso and low pressure brass.

I'd reload the cases until they split, that took some doing. These are at the end of the road & should be splitting in the next reload or 2.



It takes a little while to wear the nickel off of a case 1 reload at a time. Note the scratches the whole length of the one case. Had a bunch of them from a bad steel re-sizing die that I was using back in the 80's. It still takes allot of reloading to split them, those cases have at least 20+ loading in them since I switched to a carbide sizing die in 1986/1987???.

What you need to do is measure your 38spl "once fired" cases to see how thick the brass is. It should be 11/1000th thick when new/once fired. As the brass gets used/shot/reloaded it will thin at the case mouth. I finely had to buy more 38spl brass this year, 2000 "once fired" ww wc brass. They still had the red circle around the primer and they measured 11/1000th's.

I guess I don't understand... as I see it, for brass to split longitudinally and not start at the case mouth, two things have to be present:

1) the brass has to be hard and has to have lost its ability to spring back. For this reason, it makes sense that nickel is going to split quicker than brass.

2) there has to be sufficient room in the chamber to allow the brass to expand past its ductility point. This actually relates to #1, above...

I have been loading and shooting since 1980, and the only cases I have ever had split were 38 Special cases that were shot in an old M&P that was originally a 38 S&W. Cogswell and Harrison had re-chambered the revolver to 38 Special, and as we all know, 38 S&W brass is larger in diameter than 38 Special. The resulting chambers were large enough to split every 38 Special round fired in the revolver.

Now, having said all that, I sincerely think either the chambers in that revolver have been beaten out and stretched by too many hot loads, or that particular cylinder is soft and has stretched.

In short, I don't think the brass is to blame; at least not completely.

If I am completely out to lunch, someone please re-calibrate me. I am never too old to learn...

The only ones I ever had split at the case mouth was because I was flaring the case mouth way too much to avoid shaving the soft lead. In my defense, that was back when I was just starting out & didn't know any better.

Does anyone know what the max cylinder chamber diameter spec is for the Model 686, pre lock? My gun has not fired any"hot" loads other than less than a box of factory 357 magnum and less than 1000 target 38 SPL loads. So I do not think I have stretched or worn out the cylinder. I have not ued polish with ammonia for cleaning brass. My used brass is measuring 11/1000 wall thickness with no scratches, nicks or other stress risers..

Doubless, don't understand the reasoning behind this...

Or.......

The brass is old as heck and had too many reloading cycles. I have some brass such as this myself. Some of my old 38 Special brass dates back to the mid 70's when I got my first Model 27. All that old brass is nickel plated and I have no earthly clue as to how many times it's been reloaded, but it is a lot. I'm probably going to retire that old brass soon as it gets to be a real pain in the butt to closely examine the cases for any damage. Some of it has been reloaded enough that most of the nickel plating is wearing off.

Check & see if it is one chamber that is spliting the brass. I had this problem a few years ago & I marked the chamber & shot it again & if it split again you may have to get a new cylinder.

M586-3 cylinder chamber 0.381" , 0.382" pin enters about 1/4" , s/n BBR22xx

M586-4 cylinder chamber 0.382" , 0.383" pin enters about 1/4" , s/n BPW83xx

M686 cylinder chamber 0.381" , 0.382" pin enters about 1/2", 0.383" pin enters extractor , s/n ACK47xx

M686-3 cylinder chamber 0.381" , 0.382" pin enters about 1/2", 0.383" pin enters about 1/4" , s/n BPN09xx

M686-3 cylinder chamber 0.381" , 0.382" pin enters about 1/2", 0.383" pin enters about 1/4" , s/n BJH00xx

Measured with pin gages in a clean cylinder.


EDIT: I now have 5 dirty guns with really clean cylinders. More cleaning tomorrow.

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