.357 crimp or not crimp?

[jdjax64]

I am wanting to load sjsp 158 grn. magtech with 550 cci primer using 6.4 grns. unique. should i put a roll crimp? also my rcbs carbide die instructions say i should trim cases so that they have the same amount of crimp. how necessary is it to trim?


It should be obvious that i am new to reloading and any help is greatly appreciated, i am just trying to get bullets to go downrange without getting my head blown off, so high accuracy is not my goal right now

[dave22250]

For mag revolvers you should always crimp because recoil can be significant and bullets can move in case and cause excessive pressure, and yes case length can affect the crimp if differant case lengths

[fryboy]

you'll have to crimp at least enough to remove the flare ( case mouth belling ) the rest depends upon several factors , including the type of weapon it will be fired in , a single shot such as a encore or contender ...not so much , a lever action or a revolver perhaps a bit more crimp ,the load you listed in on the lite side of my charge tables so a super heavy crimp shouldnt be required , had you been loading one of the slower magnum type pistol powders they work best with a heavy crimp
while i agree that cases should be the same length for best results very few of us actually have to trim pistol brass , i'd measure them and see how much variation you have ( this is one very good reason to keep lot #'s of different brass separated )

[runfiverun]

i seat and crimp in separate steps.
this way you can pay attention to the crimp.
if you have any overly long cases you can change the crimp for each case length and then trim just the longer ones.
if you are using cases from new to done and keep them separated from other batches they will generally stay close enough in length you won't need to trim many.
i do like to champher the inside of case mouths lightly on new cases also

[mikld]

I rarely trim my revolver brass. Even if there is a .010" difference in length, a hefty roll crimp won't be effected. I roll crimp all my Magnum ammo, .357 and .44., for consistant burning with magnum powders and managing recoil...

[jdjax64]

thank you all for your input. i think i will try the seat then crimp method

[j1]

Damned old posts. Please delete.