Reloading shell crinkle questions [Archive] - Glock Talk

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MyTime
04-29-2014, 17:31
I could use some reloading advice from experts.

I reload 45ACP using RCBS dies. I've reloaded thousands of 45 and normally they come out fine. Occasionally I find that when I press the bullet into the brass that it seats properly but there is a circumferential crinkle below the seated bullet. What I presume is that this brass has exceeded its service live and I pull the bullet and discard the shell.

I have recently started reloading the 40 S&W after purchasing 800 pieces off of an online source. For the 40 I have Hornady dies and I've seen the same crinkle a little below where the base of the bullet seats...just like the 45 but with an increased frequency. I discard the brass and consider it a terminal failure.

So, if you have seen the same thing, am I correct that the brass has seen the extent of its useful service life or is there something that I may be doing that I need to do differently?

If you have some knowledge, please share it with me. Thank you.

MyTime

Colorado4Wheel
04-29-2014, 17:47
Is it simply that the brass is smaller than the bullet so it leaves a ridge around the base of the bullet?

SJ 40
04-29-2014, 18:34
The coke bottle effect,you are tossing serviceable brass,when a case splits then it's time to toss it. SJ 40

dkf
04-29-2014, 18:49
You should see the "bullet bulge" with my .380 115gr XTP loads.

Wall thickness of brass can vary slightly so it is more noticeable sometimes. Just so the little "bulge" is even all around the case and not just at one side.(indicator or a crooked seated bullet)

MyTime
04-29-2014, 19:34
Not sure about the cause but sure that some have caused issues with tight chambers on a couple of occasions so I started paying attention to those that proved problematic going into the chamber fully. I have the dies set to flare the brass for feeding the bullet into it and it seats properly. They are seated straight, not crooked. Other than potentially worn out brass I'm at a loss at explaining this, that's why I started this thread. I've reloaded about 30K pistol rounds, but compared to some out there, I'm a newbie and I always say I can learn from those who have more experience. Thank you for the responses so far.

MyTime

dkf
04-29-2014, 21:07
You can give suspect rounds the "plunk test" in your barrel or in a case gauge that you know if they pass the gauge they will fit your barrel.

PCJim
04-29-2014, 21:44
Pictures are always helpful. We, myself included, presume you are seeing a noticeable bulge in the case at the base of the loaded bullet. This is normal and can be more or less pronounced, depending upon the amount of sizing the case has undergone and the diameter of the bullet. Case wall thickness also comes into play, as mentioned.

If you are describing something other than this, a picture would be a great help.

Colorado4Wheel
04-29-2014, 21:53
It's not worn out brass. Get that out of your mind. Understand that brass gets thicker the closer to the base. The more deeply you seat the bullet the more you will see the brass/bullet transtion (I don't want to call it a bulge). It's normal. Most issues with the "tight chamber" are not a about this but crimp/aol or something even more obscure.

F106 Fan
04-29-2014, 23:02
Think of it this way: In order to keep the bullet in the case, there needs to be a certain amount of neck tension. This is achieved by the sizing die when it sizes the brass somewhat smaller than the expected bullet diameter. Now, when the bullet is seated, the case expands around the bullet and leaves the distinctive 'coke bottle' shape.

BTW, Dillon recommends belling the casemouth by 0.020". This seems a little large and most of the folks around here are closer to 0.010"-0.015". The bell prevents the bullet from collapsing the case while it is being seated.

Pictures would be good. You say 'wrinkle', we say 'coke bottle' but there is no good reason to believe we are talking about the same thing. If your brass actually has a 'wrinkle', there is something wrong with your process - likely an issue of insufficient belling.

Richard

Colorado4Wheel
04-30-2014, 08:20
Good post Richard.

MyTime
04-30-2014, 17:30
I keep trying to upload a pic taken with my cell phone but it says I have exceeded the size limit for uploads. If I figure it out I will post a pic. Frustrating but I'll work with a bit more before I call it quits on the pic.

dkf
04-30-2014, 17:41
Open a free Photobucket account and post the link to the picture in your post.

Colorado4Wheel
04-30-2014, 17:58
I keep trying to upload a pic taken with my cell phone but it says I have exceeded the size limit for uploads. If I figure it out I will post a pic. Frustrating but I'll work with a bit more before I call it quits on the pic.

Hit "share" and then e mail out or text it to somone who knows how to do it.

F106 Fan
05-01-2014, 17:32
I keep trying to upload a pic taken with my cell phone but it says I have exceeded the size limit for uploads. If I figure it out I will post a pic. Frustrating but I'll work with a bit more before I call it quits on the pic.

Some photos have too many pixels to post. The JPGs from my digital camera are between 4 & 5 MB. Sometimes, when I want to upload one, I bring it into some kind of image editor (probably PhotoImpact) and save it with reduced resolution. I might crop the image to save pixels as well.

If I get the image down to the 40-50 KB size range, it will upload.

Richard

MyTime
05-01-2014, 19:14
Got the wife's camera and some technical assistance.

So below where the bullet is seated there is an outward buldge, a straight line, and it can go all of the way around the case, usually not though.

So, maybe this will help those who were kind enough to comment with their diagnosis.

239415

WeeWilly
05-01-2014, 20:09
It is hard to tell for sure from that angle, but if you are seating and crimping in the same step, I would say you have your die body too far down, the crimp collar looks like it is buckling the case.

dkf
05-01-2014, 20:22
That is not from the bullet expanding the brass slightly. Looks like you buckled the case when you crimped or when you expanded the case. Most likely buckled from the crimp.

MyTime
05-01-2014, 20:26
WeeWilly,

Bullet seating and the crimp are two different steps. I am placing a light crimp on them.

MyTime

WeeWilly
05-01-2014, 21:07
It is a lot harder to buckle the case with a separate crimp die, but not impossible. Usually that kind of buckle comes when doing it in a single step, with the bullet and crimp collar all locked up forcing the case down too far. With a separate crimp step, usually the case mouth and bullet looked all screwed up, which yours doesn't.

In any case, it does look like a buckling, versus the bulge where the bullet ends as the wrinkle seems to be too far down the case (bullet doesn't reach that far).

dkf might be right about buckling with the expander.

If you could get a side shot close up of that second from left one, it would be easier to tell, I think.

Colorado4Wheel
05-01-2014, 21:50
No such thing as a light crimp on a .40. You remove the flare and nothing more. You don't crimp inward at all. Also, it does appear the buckle is well below the bullet. So I say seat a bullet, look for the buckling. If no buckling when seating bullet but you get buckling after crimp you just found your problem.

F106 Fan
05-01-2014, 23:03
It should certainly be easy to determine which step is causing the buckling. Then fix it!

Richard

MyTime
05-11-2014, 09:33
I finally got time to reload again. I removed the crimp and I have ZERO issues. I thank you all for your guidance.

I do have a couple of questions though...

With an autoloader that has the bullet hitting the ramp, why do you NOT crimp? I may be rationalizing this the wrong way but it seams that the crimp may prevent set-back.

Do you want a crimp on any autoloading pistol cartridge? A 10mm? A 45 ACP?

Thanks!

MyTime

WeeWilly
05-11-2014, 09:48
I finally got time to reload again. I removed the crimp and I have ZERO issues. I thank you all for your guidance.

I do have a couple of questions though...

With an autoloader that has the bullet hitting the ramp, why do you NOT crimp? I may be rationalizing this the wrong way but it seams that the crimp may prevent set-back.

Do you want a crimp on any autoloading pistol cartridge? A 10mm? A 45 ACP?

Thanks!

MyTime


This is a very common misconception. The taper crimp in a rimless caliber (which in itself is a misnomer, should be called case de-bell step or something else like that) is just to straighten the case back out from the belling step pre-bullet seating.

Additional taper crimping on these rounds just serves to take neck tension away (neck tension is what holds the bullet). It is pretty easy to understand actually, the brass is more springy than the lead bullet underneath, you press it down into the bullet with a heavy taper crimp and it springs back leaving less tension.

There is one exception to the above rule and it is a very limited exception. Many guys taper crimp their 45 Auto LSWC's rounds beyond just straight (like .469") for feed reliability, but it has nothing to do with holding the bullet from setback.

The roll crimp used in rimmed (like revolvers) calibers does help hold the bullet from walking out of the case under recoil, but that is a physical detent retention and again if overdone will actually reduce neck tension.

The number one giveaway of a reloader that doesn't know what he is doing is when he posts something like, "I put have heavy crimp on my nuclear 10mm loads.", etc. If you see that, ignore everything else that guy has to say.

F106 Fan
05-11-2014, 09:55
With proper resizing, there should be enough neck tension to prevent setback during the run up the ramp. So goes the theory.

In practice, I see a lot of folks suggest that repeatedly rechambering a factory round may lead to setback. I haven't seen it myself but I don't get out the calipers every time I recharge a weapon.

None of the straightwall pistol cases (including the tapered 9mm) get any kind of roll (sometimes called 'profile') crimp. Revolver loads, sure. Pistol, no. The issue is headspacing: Revolver cartridges tend to have a rim for headspacing (or we use moonclips when shooting pistol ammo in a revolver). Pistol cases tend to headspace on the casemouth. If you overcrimp the case the round headspaces on the extractor and I don't think much of that solution.

There might be an exception for the .357 SIG, a bottleneck cartridge. In theory, and according to SAAMI, the round headspaces on the casemouth. I tend to think they headspace on the shoulder, just like a rifle cartridge. I'm probably wrong...

Richard

MyTime
05-11-2014, 10:20
Well, after a decade of reloading, I just learned something. Thanks guys!