To crimp or not to crimp

I'm reloading 7m stw should I put a lite crimp or no crimp at all. Not sure what is best practice. Any help would be greatly appreciated.

I wouldn't but admittedly, don't have experience with that specific cartridge. The only things I crimp for are my .38/357 and 7.63x39 (SKS & AK) reloads. Unless I absolutely have to, I never crimp and routinely ignore cannelures for bullets like SSTs and let consistent (and sufficient) neck tension do the job.

I don't crimp unless it's magazine fed.

Typical I don't. But on guns where I have a lot of jump to the land I have played with crimping and not to crimp. I crimp 2 rifles and have seen a slight improvement in accuracy and SD. The only problem is keeping everything consistent. Can be difficult.
But general I don't because I just typically play with neck tension. Personally I would stick with playing around with neck tension. It's more constant in my opinion.

.

LexRick,
Have to agree with these guys. I don't crimp either...not even on .358 Winchesters and such. Now, I've only tried it once on a .338-06 I used to own/shoot and it made no significant difference for me in target results or SD/ES numbers for that rifle. Haven't seen the need to try it out again....

I crimp everything. Learned about it from the guys on the 7STW thread when I purchased my 7STW. There is a bunch of debate, but it has shown to make the groups a little better and drop ES for a few guys that did testing. It's up to you, but it won't hurt anything. Also, everyone that is crimping is using the Lee Factory Crimp Die

If the bullet of choice has no cannelure, don't crimp it.
I don't crimp anything, even my .223 ammo I run in my AR. Not even Hammers or LRX/TTSX with the drive bands/grooves.
I see no real way my groups can improve over this with a crimp. Various 3 shot groups from different rifles.

For rifle loads, I see the need to crimp when you have the situation where neck tension is not enough to keep the bullet from moving under recoil, or the neck tension is not uniform. The throat of your 7STW is short (comparable to the 7rem mag) but not as short as that for my WSMs, and may respond well to crimping. For comparison, take a look at the throat length of a 7mm Weatherby.

I ran a test with and without a Lee Factory Crimp and found the crimped rounds more accurate by about 25%. If you shoot a magnum with a compressed charge and don't crimp with 0.001 or 0.002 neck tension, I bet the last round in the mag has moved a bit....

Crimping adds another variable to reloading which can (potentially) improve or degrade accuracy. If your cases aren't EXACTLY the same length then the amount of grip produced by crimping will vary. That just can't be good for accuracy. But ..... with cases that are as close in length as possible I can see that crimping could be beneficial in some applications.

I only crimp 45-70, 458 SOCOM and handgun ammo. I don't crimp the 223 cases on the ammo used in my AR because there seems to be no reason to.