Texas Sheepdawg wrote:I have been reading all of the posts on crimping and quite frankly, I am totally lost.
TSD-
Your being confused is understandable. Discussion of crimping has been continual since the start of the calguns thread. Crimping topics seem to arise for three principal reasons:
First, when novice reloaders ask about the fourth die in the Hornady 450B die set. Hornady thoughlessly failed even to mention the fourth die in their instructions included with the set.
Second, when either novice or experienced reloaders ask about the use of the crimping shoulder built into the Hornady 450B seating die.
Third, when a reloader wishes to experiment with bullets, powder, and cases that fall outside Hornady's lab-tested recommendations.
Crimping is important, because the bullet needs to be held firmly through the shuffle-slam of the chambering cycle. For many of the recommended powders, a firm crimp is needed to ensure a proper powder burn. However, too much crimp can cause headspace problems because the cartridge headspaces on the case mouth, which excess crimping will distort. The balance between too much and not enough crimp is critical, and so it receives considerable attention in the reloading forum.
If one sticks with Hornady dies using the standard drill for 4-die sets of other cartridges, and if one uses the recommended components, then most crimping discussions here can be ignored. Just remember 0.476" for the case mouth OD of finished reloaded rounds.
Does this help?
--Bob