Thread: To Crimp, or not to crimp...

Hi all. I've done a quick search, but haven't seen this question asked. I've just started reloading .270wsm using RCBS dies and Hornady 130gn SST's in Federal brass. Do the reloading gurus think a roll crimp is the go? Or no crimp at all? Or a light roll crimp? Looking at the Fedral factory rounds, they appear to have a very light crimp, if any. I want the most consistent load I can get, without blowing up my rifle and keeping my hands and eyes. Any advice would be very much appreciated.
Cheers,
Ken

I crimp for both my semi and bolt action 308s. Bolt action shoots about 0.5-0.75MOA. Original stock, magazine added and not bedded. Its a hunting rifle and want my ammo to be reliable and consistent in the rough stuff. I'm also not shooting anywhere near max loads. I consider mine to be a light crimp, coming on just before the end of the stroke on the press, but by no means swinging off the thing...

No need to crimp 270Wsm.

Neck tension is more important for accuracy. Crimping is really only needed for tube mags and semis. I agree with 257, crimping is unnecessary.

i dont crimp

Crimping is for rattle guns

I lightly crimp all rifle ammo,one less thing to wory about and one of my reloding mentors swears it reduces the extream spread of velocity

Originally Posted by res

I lightly crimp all rifle ammo,one less thing to wory about and one of my reloding mentors swears it reduces the extream spread of velocity

I have found that crimping does the opposite - meddles with ES. It just adds another variable by virtue of the slight inconsistency of the crimping process that end up affecting neck tension- which you might have just gone to a lot of bother to control by things like neck turning and the use of bushing dies.
Absolutely no need to crimp , except as already stated in previous postings, tube mags and semis, and usually African type cartridges in bolt guns where there may be extreme shunting.
The only cartridge I was crimping regulalrly was for my bolt gun 32/20 and accuracy improved once I stopped - contrary to what Lee states in their blurb.

I never used to crimp. I started on my 303, it seems to improve consistancy rather than outright accuracy. I only use a light crimp and my brass is neck sized, so itw working for me.

As soon as I started using the Lee Factory Crimp on my 300 WSM loads, ES and SD halved....accuracy was the same so it works for me...

Give it try and see how it works for you. Come back to us with your results. That might change the mind of a few.

Make sure your cases are all trimmed to the same length or it's a waste of time, just turn the case mouth in, to much crimp can damage the jacket
If you have a .223 or .308 you can get taper crimp dies which would be the best type to use.

Thanks Guys. Looks like I'll have to buy a case gage and bushing die to get the neck tension right. Might try crimping just a few, see what happens. Take care, all.
Cheers,
Ken