[Kentucky Rifle]

Hi guys. I don't usually visit your section because I don't reload. However, I'd be obliged if a few of you could answer a queston or two.
Generally, how much pressure (in pounds) do you put on the crimp of a jacketed bullet/brass case. (Revolver. non-roll crimp.) Take a .38 Special or .357 Magnum for example.
Then, if you please, give me an example of a case with a lead bullet.
I hope I've made sense here. Being a non-reloader puts me at a disadvantage with the terminology.

Thank you kindly,
KR

[Archie]

For revolvers in general, normally one adjusts the crimp until the case mouth is firmly seated in the crimping groove. This applies to either jacketed or lead bullets. Revolver rounds are typically roll crimped; that is, the case mouth is "rolled" into the bullet.

Too little crimp will allow the recoil of the revolver to actually pull the bullets out of the case, further, it hinders proper ignition of the powder charge.
Too much crimp over works the case mouth and deforms the bullet. It can distort the case so much it won't chamber.

Taper crimps are normally used for auto pistols. The crimp serves the same purpose as in a revolver; that is, hold the bullet in place during initial ignition (to assist in a consistent powder burn) and hold the bullet in place. Except in a semi-auto, one is attempting to avoid the bullet being pushed deeper into the case while in the magazine.
A taper crimp squeezes the case mouth tight to the bullet, but leaves the case parallel to the bullet sides. Also, the case mouth must remain at a size to butt up against the end of the chamber. I have seen crimps for auto pistols described by the resultant outside diameter of the case mouth.

Have I confused you enough for one day?

[Jeeper]

There would realy be no way to measure the pounds applied to a crimp. All presses have different length arms which would change the mechanical advantage and the resulting pressure. THe post above was right.

[Edward429451]

Setting crimp is mostly a visual thing, at least with roll crimps. Trial & error until you like the looks of it. Directly in the center of the cannelure, crimped to the bottom of cannelure. Similarly in lead crimping grooves but to the top of the groove.

Auto pistol/taper crimped rounds can be miked and adjusted down to the specs in the load book for outside case diameter or crimped and measured for OAL, then stand the round on a bathroom scale and push it down with the heel of your hand to 30 lbs or so and remeasured for OAL. Any setback means more crimp is needed. You can also double check them by carefully cycleing a couple through your gun manually (rule #2!) and checked for OAL before/after.

[P95Carry]

Archie pretty much buttoned this up ..... so little to add at all. Certainly ''poundage'' is irrelevant .. it's all down to die settings. The distance between crimp section of die and case mouth is all that matters ... and usually a few rounds need loaded to get optimum crimp setting .. I usually use older cases (trimmed) and then shoot em off later.

I do like to find that bullet will not rotate in case ..... whether roll or taper ..... and with hot loads like .357/44 etc .... a crimp into cannelure or grease groove will usually retain bullet under recoil .... too much of course work hardening case mouth excessively and shortening case life.

If case distorted thru over crimping ..... then ...... something really was over ''generous''!:rolleyes: :D

[dodgestdshift]

Revolvers take a roll crimp. When you have crimped push the cartridge against a hard flat surface. If the bullet moves you need more crimp. If you over crimp you can damage the bullet, or cause it to be moved when the bullet is twisted.