Crimping question

[3gunfreak]

.40 caliber 180 gr Hornady over 4.0 grams of Bullseye powder on a Dillon 650.

My question is :If I back off my crimp some, will that help me dial in my grouping. Right now I am grouping about 10 shots in the size of a softball but I feel like I can get them tighter. Is the correct crimp that crucial or should I start a new work up with more/less powder?

Any help would be appreciated in my eternal search for accuracy.

Thanks

 

[SmokinTom]

You really should try a Factory Crimp die if your not useing one.

 

[Robert M Boren Sr]

How far are we talking about on the grouping? The crimp isn't usually the culprit, I would try using a bench rest and then messing around with powder or bullet brand before I would mess with the crimp.

 

[JDG]

If you dont bell your case too far, seating the bullet pretty much irons out the belling. Lee FCD are nice, since it seperates the seating from the crimp, but really theres not much to crimp if your belling to the minimum If anything the FCD makes a nice radius on the case mouth, and post sizing is good insurance.

 

[circle141]

crimp

Sir.

The 40 cal. head spaces on the mouth and should have a taper crimp only. Any other crimp will change the head space.


Mike Circle

 

[JDG]

Bad choice of word The FCD for the 40 S&W is a taper crimp, and it leaves a nice finished edge when performed correctly.