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Is this incipient case separation?


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Guest Lester Weevils

It is hard to tell from the picture, but some brass, often the nicer self-defense rounds, have an intentional machined-in circle about 2/3s up from the bottom, most likely the same position as the bottom of the seated bullet in the factory round.

If it isn't intentional machining, maybe those rings in your picture are suspect.

I usually notice "case separation" rings near the bottom of a case. But splits or "incipient splits" at the case mouth are the most common defects I see. Sometimes you can just look at a non-split case mouth and make a fair bet its gonna split when it gets belled or the bullet seated.

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Lester, it is interesting that you say that. The reason I posted this thread is because they kind of looked machined. It is not a smooth ring all the way around but rather a kind of perforated look which is why I began to suspect that it might be something else. However they are at different heights. If I can't get a positive answer I'll probably keep throwing them away because they have amounted maybe 2-3% of the total brass I have collected so far. If in doubt I will definitely err on the side of not blowing my gun up in my face. :)

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I've seen this brass before in some I've picked up at the range. I believe it's just a factory crimp mark.

Still being new and wanting to be extra careful I have been throwing these away. Is this an indication of incipient case separation or something else of which I am unaware? I am referring to the rings around the cases.

Separation2.jpg

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Look like factory crimps to me. Are those brass cases Aguila by any chance?

I did have one or two that was Aguila, but in this group the .40 is Federal and the rest have FC as a head stamp.

If this is factory crimp can I assume that it is safe to reload as usual?

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Guest Lester Weevils

Yes the factory rings usually have a perforated or dimpled look, but it is strange that intentional crimps would be at different heights unless the QC was incredibly bad at the factory.

PS: I don't know if it is safe to reload the factory-crimped cases, but I've always done so with no bad results so far. Hadn't thought about it.

Edited by Lester Weevils
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Yes the factory rings usually have a perforated or dimpled look, but it is strange that intentional crimps would be at different heights unless the QC was incredibly bad at the factory.

I think we have a winner. When I set them on end and looked more closely they seem to be at the same height after all. I think this must be factory crimp. It's funny I've never noticed it on any of the ammo I've shot but I'm definitely seeing it now.

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Guest Lester Weevils
These are purposefully made indentions in the brass, put there by the manufacturer to prevent bullet setback.

Cowboy action shooters will be familiar with 45 colt cases that have the same.

I've seen them on some 9mm, and they seem very common on .357 mag rounds.

Caster, are you aware of any way that amateurs could make such a crimp ring to prevent setback?

I've loaded some .380's with a run of 90 gr XTP bullets which are speced at .355 but in reality they measure closer to .354.

Maybe there is some other reason they are subject to setback, but I suspect they are just a little too small for the thin .380 case to hold em. Even with an overkill top crimp those bullets are too easy to push back into the case. The case is sized correctly and they fit a chamber case gage perfectly. Just need something else to grab the bullet a little better.

.380 cases are probably not strong enough to survive being put in a lathe, but some kind of well-supported rotary Knurling tool might work on the loaded ammo (gently applied).

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No.

BUT, there may be another option. Try using a filler like cream of wheat. You'll have to be start all over with load development and pay close attention for pressure signs, but you can use a case filler over the top of the powder charge so there is no empty space for the bullet to go.

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it is referred to as a case cannelure much like a bullet cannelure it has a purpose(crimp groove),.. to keep bullets from setting back in heavy loadings and oddly enough all my Remington 148 HBWC target brass has one also.

Corbin makes a tool for ,45-70 Govt. and explains its purpose it is put in after loading to help set the bullet and is removed ( internally) upon firing due to the softness of the shell casing but the outside marks stay there..

Load em and shoot em.. I lost track of how many I have reloaded over the past 20+ years..

incipient case head separation has more to do with bottleneck rifle casings "growing" and being trimmed too many times or really bad headspace problems, the brass has to come from somewhere and is internal down by the base found by sectioning a sample case or using a paperclip with a bent end to "feel" for it have yet to see/hear of a straight walled case do that,..they tend to shrink with use it seems until they split at the mouth

John

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Guest Lester Weevils
Caster, are you aware of any way that amateurs could make such a crimp ring to prevent setback?

I've loaded some .380's with a run of 90 gr XTP bullets which are speced at .355 but in reality they measure closer to .354.

Maybe there is some other reason they are subject to setback, but I suspect they are just a little too small for the thin .380 case to hold em. Even with an overkill top crimp those bullets are too easy to push back into the case. The case is sized correctly and they fit a chamber case gage perfectly. Just need something else to grab the bullet a little better.

.380 cases are probably not strong enough to survive being put in a lathe, but some kind of well-supported rotary Knurling tool might work on the loaded ammo (gently applied)?

No.

BUT, there may be another option. Try using a filler like cream of wheat. You'll have to be start all over with load development and pay close attention for pressure signs, but you can use a case filler over the top of the powder charge so there is no empty space for the bullet to go.

Thanks Caster

A filler might do the trick. Hadn't thought of that.

Have seen rare internet claims about Trail Boss powder in .380 though the company doesn't recommend it for that caliber. Tis said that Trail Boss is so fluffy that you can fill a case on most things without getting in too bad trouble.

I can think of possible side-crimp tools which I do not have enough expertise to fabricate. Am pretty sure I don't have any electronic crimp pliers with as big a diameter as a .380, but maybe there is such a beast somewhere.

Hmm, maybe one could attach facing pieces of piano wire to the jaws of a vise, and carefully knock a crimp right behind the bullet by gently squeesing three times, rotating the round by 60 degrees between each squeeze? Choose piano wire diameter for the width/depth of crimp desired?

Would most likely need to run the loaded round thru a resize die after crimping to get it back to round, and maybe hit it again with the bullet-crimp die.

On the other hand, for a bullet-setback crimp just to "save" a couple of hundred loaded rounds, maybe it would only be necessary to crimp each bullet one time each in the vise? The crimp wouldn't have to be pretty or concentric as long as it would prevent setback? Just put two opposing dents in each round and then resize to make it round again?

Just idle thinking about it. Maybe a silly idea.

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These are purposefully made indentions in the brass, put there by the manufacturer to prevent bullet setback.

Cowboy action shooters will be familiar with 45 colt cases that have the same.

This^. I reload the factory cases with perforated indentations just like any other cases and have never had any problems.
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Thanks Caster

A filler might do the trick. Hadn't thought of that.

Have seen rare internet claims about Trail Boss powder in .380 though the company doesn't recommend it for that caliber. Tis said that Trail Boss is so fluffy that you can fill a case on most things without getting in too bad trouble.

I can think of possible side-crimp tools which I do not have enough expertise to fabricate. Am pretty sure I don't have any electronic crimp pliers with as big a diameter as a .380, but maybe there is such a beast somewhere.

Hmm, maybe one could attach facing pieces of piano wire to the jaws of a vise, and carefully knock a crimp right behind the bullet by gently squeesing three times, rotating the round by 60 degrees between each squeeze? Choose piano wire diameter for the width/depth of crimp desired?

Would most likely need to run the loaded round thru a resize die after crimping to get it back to round, and maybe hit it again with the bullet-crimp die.

On the other hand, for a bullet-setback crimp just to "save" a couple of hundred loaded rounds, maybe it would only be necessary to crimp each bullet one time each in the vise? The crimp wouldn't have to be pretty or concentric as long as it would prevent setback? Just put two opposing dents in each round and then resize to make it round again?

Just idle thinking about it. Maybe a silly idea.

Don't do this. It squeezes the bullet at the same time as the case but the case springs back and not the bullet. This makes the bullet undersized and will generally just fall out out of the case. And yes I have done it so I do know first hand.

As far as the case crimp goes it is applied so it grabs the bullet to prevent them from working out from heavy recoil. The crimp is not below the bullet but aplied somewhere on the bullet or at least they are on calibers generally used for revolvers. This is why you see 357's crimped, not because the bullet it going to be setback from chambering like on an auto but because recoil can cause the bullet wot work out of the case. The same style of case crimp also prevents bullet setback in semi autos.

Heavy recoil does not cause the bullet to be set deeper in the case. The bullet can be set back in a semi auto upon chambering but not from recoil. The recoil can cause a bullet to be pulled from the case. And in most cases they also have a crimp at the case mouth that way there are two crimps holding the bullet in under heavy recoil. And in a revolver it can lock it up tight as a drum. Hense the need for a sturdier crimp.

Dolomite

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Instead of filler you could just use a weaker powder to fill the case, or get a different bullet, maybe one with a crimp ring, if those are causing problems. Filler adds a step and slows you down, if nothing else, it seems like a last resort fix to me (what happens to the powder's burn rate and all if they get shaken up and the powder/food is all mixed together? )

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Guest Lester Weevils

Thanks Dolomite and Jonnin

Had bought 500 XTP HP 90 gr for the .380.

I don't shoot .380 much, and even less lately after semi-retiring the tiny little NAA .380 as too inaccurate in my hands to carry for defense, and too unpleasant to shoot for fun. It could probably be shot accurately by someone more skilled, but that someone ain't me. Those XTP are the only ones I've loaded in .380 so far. Hornady makes good stuff and those are the only Hornady bullets I've measured that were not the exact diameter advertised. Maybe a quality control defect on that run.

Sometime might get a Beretta Cheetah if find a good price on one, just because they are neat pistols. A good price on a Cheetah seems rather unlikely though. And have been thinking about maybe getting a p238 though I need another pistol like a hole in the head. :) So might shoot more .380 in the future.

Loaded a few test rounds with "normal slight crimp" and noted the setback problem, then discovered that the bullets measure slightly undersize. Didn't measure the bullets til noticing the setback problem. Never had setback problems before. Then made a more aggressive crimp which holds the bullets "kinda sorta" tight but not as tight as I'd like, and loaded 300. Of which about 100 have been used up.

Might use the remaining un-loaded 200 XTP 90 gr as high velocity loads in 9mm. I have a feeling that the thicker case of a 9mm would hold onto the bullets better. The .380 brass is just so dang thin. I will buy some other kind of bullet for loading any future .380 practice rounds. I had got the XTP 90's in the bullet shortage period when all other brands of .380 bullets were out of stock.

Those 200 rounds are loaded so light with W231 it seems doubtful they would be especially dangerous if they got set-back on feeding. Especially in a blowback gun. The first 100 didn't blow up and I know some of them got set back some before firing. The .380 brass can't hang onto the bullets worth a dam, so one would think they would just scoot out real quick before overpressure would be much of a problem. But I'm just cautious about such stuff. If I could lay some kind of slight crimp behind the 200 loaded rounds, it would just be a little peace of mind. OTOH it might be cheaper to just discard them rather than mess with it. :)

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Guest Lester Weevils

For what its worth-- LngRngShtr already mentioned this, but discovered that the Corbin tool he mentioned will cannelure many/most straight cartridge rounds and also bullets. Not just 45-70.

Corbin HCT-1 Hand Cannelure Tool

At $140 it isn't a bad price considering, if one needed to do enough canneluring to justify the cost.

CH Tool and Die sells one for about half that which would probably work for cartridges, advertised mainly for canneluring bullets. It appears well-made and such, but for loaded cartridges the Corbin tool looks better.

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