I gave up using the crimp in the rifle loading dies a long time ago. I found it to be too inconsistent. Went without crimping for many years, which when shooting bolt action rifles is not a big issue. ButterBean turned me on to Lee Factory Crimp dies a few years ago and I found that by doing a light crimp it evened the breakoout force, if you care to call it that as well as delayed the bullet from jumping by just a split second which increased the pressure and muzzle velocity a very slight amount, but resulted in more accurate ammo since all the bullets left the case at approximately the same pressure resulting in an increase in accuracy. 1 or 2 10ths of an inch smaller MOA means a lot to a fussbudget like me.