To crimp or not to crimp?

[H2OFUZZ]

I am shooting the 180SMK out of a 7mmSTW at 3140fps would you guys recommend crimping or not? Also do you think that is a good speed for this caliber? Thanks in advance

H2o

[backwoods83]

With that much grunt already, use a crimp and you will hurt yourself and the rifle.

[Kevin Thomas]

Crimps are fine and dandy for some applications, even necessary for one or two. But for the most part, they're a waste of time if you've got adequate neck tension. They hurt accuracy more often than they help it, but that might be something you want to experiment with. It means an extra step in the reloading process, and whichever type you chose (assuming you do), move in small increments and see what effects it has.

[H2OFUZZ]

Ok good to know. I have not been crimping so i think ill keep up with the way i have been doing it. Thanks for all the help.

[bowhunthard]

I recently started crimping my .308 Win. with the Lee Factory Crimp Die. Since then I have noticed a tighter ES and SD reading thru my chrony (low teens ES, like 7-8 SD). No real difference in accuracy, but maybe an average velocity increase of about 20 FPS, I'm gonna try doing this to my .22-250 next. We'll see what happens with that.

I don't anneal my cases yet, I don't believe you have to crimp if the cases are annealed and the neck tension is uniform.

[338winmag]

I was on board initially regarding using Lee Factory Crimp dies but now I am on the fence trying to decide if it is even worth the ammo and testing time.

The Positive:
I "think" I got closer ES groups. The reason I say "think" is because one just can't tell with 20 rounds. One would truly think with the logic that smaller ES, the tighter the groups. Again I think I got tighter groups but will have to test some more.....

The Negative:
I work extremely hard in my reloading to get everything as consistent and exact as possible and that goes for my seating depth (for every single bullet). regardless if there is or is not a cannelure, using the Lee Factory Crimp die can and does move the seating depth. If moved, it can be +- .003-.007. Sometimes it doesn't affect the bullet seating depth. If this was predictable, then great, i could take that into consideration when performing the initial seating depth, but it is not.

I called Lee and asked about this. I get an affirmative that it can affect bullet seating depth. So one might get smaller ES groups but if one is changing the seating depth, you can increase your POI groups. Like any other tool, I might probably find the very happy medium for each caliber, but then again not so sure so .......

Thanks
3382Winmag

[boomtube]

"..would you guys recommend crimping or not? "

Simple question. Simple answer; try it both ways and tell us what happens.

There's likely to be no real difference at all.