I'm very new this so here goes I've got a lee loadmaster I'm read to start making .357 magnums I just am unsure if I'm flaring too much and if I'm crimping enough. Could anyone tell me what a good measurement for a flared .357 case would b? Also how do I know if I'm under or over crimping?
New To loading question about flare and crimp on .357
- Thread starter bscriver
- Start date
For flaring, adjust so as the flare is just large enough to easily slip just the base inside the brass. You don't need any more than that. Too little and you might damage the base as with an unflared case.
For the roll crimp, it's really hard to feel with the loadmaster when using it progressively. Watch the video on Lee's website and then adjust accordingly. You want the die and seater adjusted just where it inserts the bullet to the right depth and a little extra effort on the handle pushes the case against the stop inside the die forming your crimp. You just want enough to roll slightly into the groove to hold the bullet.
I use my turret press (or even with the loadmaster one round at a time - ie non-progressive) for revolver rounds now just because it offers a little more tactile feel when doing the roll crimp.
I usually end with the Factory Crimp Die, just to post size the case in case it bulged a little from the roll crimp operation.
For the roll crimp, it's really hard to feel with the loadmaster when using it progressively. Watch the video on Lee's website and then adjust accordingly. You want the die and seater adjusted just where it inserts the bullet to the right depth and a little extra effort on the handle pushes the case against the stop inside the die forming your crimp. You just want enough to roll slightly into the groove to hold the bullet.
I use my turret press (or even with the loadmaster one round at a time - ie non-progressive) for revolver rounds now just because it offers a little more tactile feel when doing the roll crimp.
I usually end with the Factory Crimp Die, just to post size the case in case it bulged a little from the roll crimp operation.
bell enough to start the bullet and unless you are loading for rifle..
there shouldn't be much of a crimp..
the bullet shouldn't move when you smack it on the table (from either end)
if the round won't chamber then you haven't crimped enough
there shouldn't be much of a crimp..
the bullet shouldn't move when you smack it on the table (from either end)
if the round won't chamber then you haven't crimped enough
I would add that it depends on the powder you're using. If you're using regular fast-burning pistol powder in your .357Mag loads, you're fine with a minimal crimp (just enough to prevent the bullets from being driven out by recoil).
If you're using slow-burning ball powder like H110, however, you'll need a heavy roll crimp to ensure proper and complete ignition.
If you're roll-crimping, you'll know you've over-crimped when your case buckles in the die.
If you're using slow-burning ball powder like H110, however, you'll need a heavy roll crimp to ensure proper and complete ignition.
You'll know you've under-crimped when the bullets in the inactive chambers are driven out by recoil and lock up your cylinder.
If you're roll-crimping, you'll know you've over-crimped when your case buckles in the die.
