Not so Fast, this is not an easy place to discuss crimping. I will try to explain where the crimp part of the die is located and how to adjust when a crimp is desired, but, I feel why and when is as important as how.
If your cases are not the same length, forget about it, crimping a rifle (bottle neck) case is nothing but the very last step in seating (or after seating) and only requires a touch an the end of the ram travel. Again and Again, when seating, the case is not supported, this creates a problem when the case is forced to squat (bulge) because of excessive crimping. To check the height of cases (tall), make a limbo bar with one end higher than the other, if you are in charge, make it .010 thousands height difference from one end to the other, aids: feeler gage, book of 'sticky notes' (3M), once the bar is set up, mark the area under the bar in numbers from R to L, or L to R, you are in charge. To use the bar pass a case underneath, if the case passes under, slide it across to the low side until the case makes contact, then seperate your cases by height, for the purpose of crimping because crimping starts at contact, if the cases are not the same length, some cases will not be crimped and others will have more, MORE, is the problem, there is no place for the (unsupported) case to go but out in the form of of a wrinkle and or bulge, the case will start to collapse.
Roll Crimp, the bottle neck seater die has a roll crimp at the end of the neck portion of the die, it requires 'no effort' to crimp, it is less than the weight of the handle. The crimp, if used, must be at the very end of the end travel, the only way to obtain this is to adjust the die down until it contacts the crimp portion of the seater die with the ram up (MAXIMUM UP), again if the cases are not the same length, forget about it.
When to adjust: after seating for the desired over all length, raise the seater plug, with the ram up adjust the die down until the roll crimp portion contacts the roll crimp contacts the mouth of the case, that is it, secure the lock nut, NOW, with the ram still up and the cartridge still in the press, lower the seater plug down to the bullet, then tighten the small locking nut, both the seater plug and roll crimp is adjusted to end at the same in travel, if a different length case is to be used, a small adjustment must be made, seating first, then adjust the crimp, then adjust the seater plug down to make contact with the bullet, with practice and a feeler gage, the process is repeatable.
F. Guffey
F. Guffey