Crimps importance in revolver loads???

[Blueduck]

Crimp, is one area I really felt kind of let down information wise from my loading manuals and dillion instructions. I mean too little is pretty clear but what are the signs of too much?

Another question regarding this is how much effect do you think it has on accuracy in standard revolver loads. Think it would be worth the trouble to load up 5 of each at various levels between just enough and a little below too much to see if I get any noticeable gains???

 

[HSMITH]

If you buckle the case you have too much crimp on revolver rounds. On light loads I make sure I get the case rolled into the canelure and the bullet is tight, on heavy loads I crimp until the case buckles, back it off an 8th of a turn and go to loading. I have never seen a difference between heavy and moderate crimps as far as accuracy goes, if anything the heavy crimp is a tad more accurate. I load most of the light loads now with really heavy crimps too, too lazy to adjust my dies and see no compelling reason to do so. If you have ever had a bullet pull in the cylinder of a revolver and bind it up it was the LAST time you ever went with a light crimp!!! Maybe someone else has done some scientific testing, I think you can't get it too heavy.

 

[WESHOOT2]

NO EXCEPTION

Redding Profile Crimp die, 'heavy' (edge of case mouth arced into groove) for 'heavy' loads, not-so-'heavy' for the rest.

Your results will not vary. Experimentation and practice required.


[Top accuracy shooters consider a case 'used up' after a maximum of three loadings due to the working the case neck affecting consistency of its tension on the bullet.]







"Too much" shows up as a buckled case; work the other way

 

[mete]

There are two parts to this , crimp and neck tension. both are important especially for magnums. They prevent bullet jump from recoil and insure proper combustion of the powder. I have seen data that shows that too much crimp affects accuracy, and of course it also reduces case life.

 

[stans]

In an informal test using 357 Magnum brass, 148 gr hard cast DEWC's, 3.6gr W-231 and WSP primers, I found that rounds that had no crimp, just removed the flare from the case mouth, were less accurate and had much great velocity variations than rounds that were given slight to moderate amounts of roll crimps. I now crimp all revolver rounds and I agree that the amount of crimp does not seem to matter until you begin using really slow powders like W-296 and H-110.

 

[Tony Z]

Depends on the load. For very light 38/357 148 Gr Wad Cutters, I put a very light crimp on, using the Redding Profile Crimp die. For Non WC's and heaver loads I increase the crimp. There can be a fairly fine balance between performance and accuracy.
I agree with WESHOOT its something that takes practice, Also agree with the Redding Profile Crimp die for revolvers.

Tony