Is it possible to crimp too much? ;-)

[braindead0]

Had my first Squib in 10+years ;->.. . no powder.. This is in a .357 mag case, with a 158gr LRN crimped with a redding profile crimp die.

The interesting thing is, the primer only moved the bullet approx. 1/16" or so.. didn't jam my GP-100 (which was good, was in the middle of trying to down 15 playing steel plates)...

I'm not complaining, and when I'm loading it doesn't feel like I'm crimping too heavy... Just curious if I should perhaps back off the crimp a wee bit..

edit: Standard primer, not magnum.

 

[Jeeper]

My personal opinion is that almost everyone crimps too much. Excessive crimp can really mess with accuracy. The difference in the area due to the crimp should only be a few thousandths.

 

[Hkmp5sd]

Either you crimp too much or I don't crimp enough. My last primer-only .357 made it 2" down the barrel of my GP-100.

 

[braindead0]

The difference in the area due to the crimp should only be a few thousandths.

Huh? Do you mean the diameter? Not sure what you're talking about here ;-).

Bear in mind that I'm using a profile crimp die, not a simple roll-crimp.. As far as accuracy, the accuracy of my loads is as good as I am and most likely a lot better. I've tried a variety of crimp 'levels', and found that if I go too light with some powders (W296 and AA7 in particular) I do not get full burn and end up with way too much unburnt powder....

 

[P95Carry]

IMO excessive crimp is primarily just going to shorten your case life for reloads .. it work hardens the brass way quicker - and so premature splits..... after which ''no more crimp''!!

The priority I feel is consistency ..... same crimp on all rounds .... and i now use Lee factory crimp dies, both for roll on handgun loads and taper on rifle. I try to crimp so as to not be able to rotate bullet at all .... but not so aggressive as to radically distort the case mouth.

I have in the past ... with target 38 loads ... managed something approaching 20 reloads from cases. These of course were not for ''best'' ammo .. but it can be done.

 

[braindead0]

I'm up to around 15reloads on all my cases, I've had one split out of the 1000 or so I cycle.. As far as consistancy, the die doesn't come off my die holder ;-).. Pretty sure it's good to go in that respect.. I did back it off a while back (pulling bullets took a few more whacks that I thought it should), which was well after this box was loaded..so perhaps my crimp is a bit looser now.

 

[Standing Wolf]

When I first started reloading, an old-timer told me wise reloaders always check the tray of charged cases before adding bullets to cases, seating them, and crimping the cases. That was back in the days when progressive reloading gadgetry was expensive and unreliable. It adds about 30 seconds to the time required to load a box of ammunition.

As for crimps: too tight a crimp can bulge a stright-walled pistol case.

 

[CMcDermott]

I did the no-powder mistake when I was working up some loads in 41 Magnum - and the bullets never moved. The primers were backed out of their pockets some and pressed against the recoil sheild resulting in the cylinder getting tied up. One of the purposes of a good crimp is to let the pressure build to a higher level before the bullet starts to move. This gives more consistant ignition of the powder hopefully resulting in a lower velocity spread and cleaner burning.

There should be enough neck tension so that the bullet shouldn't be able to be turned by hand once it is seated, without being crimped. You are probably expanding the case neck too much when belling the case, then trying to fix it with the crimp. This is the wrong approach, make sure your sizing die is giving you enough neck tension to start with, and you aren't expanding the case too much when you bell it. I recommend using Lyman's "M" dies to expand the case mouth. If the case gets expanded too much put the expander button in a drill and use some fine grit emory clothe to reduce the diameter a little.

 

[WESHOOT2]

YEP

I've seen bullets with their head crimped off; I've seen bullets with their plating buckled; I've seen crimp so hard-n-heavy yet it STILL wouldn't secure the bullet (okay, that was me and some experimental NOYB stuff); most common crimp error is over-crimping to the point of slightly buckling the case, thereby thoroughly removing ANY possibility of neck tension.


Old old gun-rag, writer made funny joke about TV newsman worrying about "the perfect" crimp.

Testing required.

I don't care one whit about 'case life'.

 

[braindead0]

I've only ever had buckled cases when crimping and seating at the same time, and on .380ACP and .45ACP (crimping too much).

I just did a test, loaded up a squib with a magnum primer and fired it. Bullet got into the forcing cone, and that's it. I think I'm okay on my crimp.

Brings up another issue, I need to practice catching squibs. I was hot in the middle of a plate shoot when I got this one, had it actually entered the barrel...well.. I woulda had a kerblooie for sure! I'm pretty sure I remember hearing a quiet 'pop', unlike a failure to fire the primer... but...

I think perhaps I need to load up a few hundred rounds with some primer only mixed in *and* some dead primer (a shot of wd-40 outta do the trick)...mix them up (and mark the boxes of course, I'd hate to take them into an event ;-). Now, it seems to me that the *prudent* thing would be to always stop and check the barrel after a failure...but I think that would be a bad habit to get into if you were in a SD situation. perhaps with some primer only/dead primer my wife and I could practice discerning the difference...

Not that I expect any more of these, but all it would take is one ;-)