Is this 5.56 crimp ordinary?

[DustyGmt]

Got a couple cases of Winchester Q3131 and probably 80% of it has this gorilla crimp on it. I've never seen them with such a pronounced crimp so as to cause a lil raised lip at different spots along the diameter of the case mouth, did the best I could with pics.

Is this normal and is there anything about these crimps that are potentially problematic?

I have not tested it but I didnt know if anybody has had XM193 or Q3131 with these hardcore crimps and experienced any issues. I have never run across a batch of ammo with a crimp to this extent...

These cases oddly from winchester have lot numbers from each 20rd box that say "LCxxxx" and it made me wonder if they were packaged at lake city or something but its head stamped "WMA" with NATO cross...idk.

 

[Walkalong]

It's a "stab" crimp, much like the Lee "factory" crimp die for rifles. It uses a collet to squeeze the case at the case mouth, usually in four segments.

That is fairly heavy, if that is the question.

 

[Spade5]

Thanks for the post. I found some of these in some range brass I was given and could not figure out what the heck caused it.

 

[sparkyv]

I have some like this, FED American Eagle. As long as it feeds, it should be just fine.

 

[rbernie]

All of my Winchester military ball 5.56 NATO has looked like that, over several decades of observation.

 

[mcb]

Yep normal. Its a collet crimp.

 

[lightman]

Like Walkalong says, its a stab crimp, and pretty common. The one pictured may be a little more aggressive than normal. You also see stab crimps on primers sometimes.

 

[DustyGmt]

Thanks for the input. Just wanted to make sure it was g2g. I have fired many thousands of rounds and have only recently seen this style of crimp.

 

[jonnyc]

"It's a "stab" crimp"

Well, to be technically correct, it's actually a "stake" crimp. A "stab" crimp is a dot impression on the neck, below the case mouth.

 

[Walkalong]

Well, SAMMI was no help.

A method of securing a bullet or primer into a metallic cartridge case by means of multiple indentations.

https://saami.org/glossary/stab-crimp/

 

[Walkalong]

https://forum.cartridgecollectors.org/t/odd-4-stake-primer-crimp-on-new-retail-ammo/28442

I have always called the type of bullet crimp pictured a stab crimp, I really don't know where/when I picked that up or if it is technically correct.

Same thing with primers, I have always heard/used "staked" for primer crimps, but again, I don't know how technically correct that is.

 

[Riomouse911]

I’ve seen old Kynoch elephant gun ammo with three or four dimpled crimp-impressions into the bullet located below the case mouth, I think those are the stab crimps folks are talking about?

(Image is down the page a bit)

https://revivaler.com/the-600-nitro-express/

Stay safe.

 

[jonnyc]

Simple...if it looks like a dash it's a "stake"; if it looks like a dot it's a "stab".

 

[Legionnaire]

I love this forum. I learn new things all the time.

 

[10MMGary]

All of my Winchester military ball 5.56 NATO has looked like that, over several decades of observation.

Same here.

 

[loose noose]

Like wise I'm sure, never too old to learn a thing or two. That crimp looked like the crimp that was on a good friend of mine's Dad's 600 Nitro Express SXS, that we each shot one round from it about 25-30 years ago. BTW we only had 5 shells with it, but that is all it took to realize it wasn't meant to be shot on a regular basis at a 55 gallon drum.