Seat and Crimp same step question

[gonoles_1980]

I have Lee dies, and I'm doing this with 38spl and 357 cases. I turn my 3/4" of a turn, seems to make for a nice crimp in both the Missouri/Xtreme LSWC and the Speer LSWCHP. I have been debating going to just a 1/2 turn. I'm curious as to how much of an extra turn you use on your die for the crimp?

 

[jmorris]

Extra turn from what? I stop when I get the results I am looking for. If it’s not enough, I go more but I don’t go past “that’s good” by any amount.

As far as a roll crimp goes, just compare a factory round to yours and adjust accordingly. Should keep you in the ball park.

 

[PO2Hammer]

I never count turns, I adjust the die and measure the crimp with a caliper.

 

[mdi]

I too, crimp "by eye" meaning I look at the crimp and determine if it's the correct crimp for the load, the bullet, and the use. In '69 I was reloading 38 Special with a Lee Loader and copied the amount of crimp that was on some factory ammo I had. I graduated to a bench press using Lee dies and followed the "add 1/2, 3/4 turn" guideline but in some instances, it was too heavy and for some loads too light. I started reloading 357 Magnum and found I needed a heavier crimp so I added crimp until all bullets stayed in place. All the crimps I use today are from my experience/experimenting from that first "copy the factory" crimp. Basically I like to see the case mouth rolled into the crimp groove a few thousandths. If my bullets "walk" I'll add a bit more.

I have been reloading for quite a while and I still separate the seating and crimping steps. Very early on I tried to combine the process, but getting the adjustments "just right" was a pain and I felt I had more control on both steps when done separately. But many combine the steps successfully. For ease of seating/crimping separately, I just got a second seating/crimping die and instead of adjusting form seat to crimp, I just swapped dies...

 

[Toprudder]

"Factory crimp" can vary. I have some 357mag factory ammo that has no visible crimp, but they do use some type of glue to hold the bullet.

The only time I like to crimp and seat in the same step is when there is an actual crimp groove, not just a cannelure. I don't personally like the idea of crimping into the bullet while it is still being seated, but that may just be me. I crimp just enough to prevent bullet setback or jump.

 

[buck460XVR]

Kinda depends on your bullet, your powder charge and how long you want your cases to last. True bullet diameter varies and does depth of the cannelure. Some plated bullets have no cannelure. Amount of recoil produced and what gun my .357 loads will be shot on also determines the amount of crimp I give. Some powders like H110/W296 and IMR4227 prefer a heavier crimp for better ignition. Heavy recoiling loads need more crimp to prevent bullet jump. Still, I try to avoid heavy crimps(same when flaring mouths) when not needed to give, my brass the longest life possible. Your directions that came with your dies are the best place to start. Experience will tell you as you go on whether or not you can get by with or need, less or more.

 

[PO2Hammer]

There are some excellent pictures around here of crimps, mostly from our moderator Walkalong.
Do a search here on THR for crimp and you should find quite a few.
Light loads don't need much crimp at all.

 

[gonoles_1980]

A little different set of responses than I expected, interesting though. It did create a discussion which is what I was looking for. I still use different steps for seating and crimping on plated bullets. I've probably done over 1000 rounds on the lead bullets with a crimp grove on the lead bullets, have tried both a 1/2 turn and a 3/4 turn on both, really don't notice a lot of difference when shooting. I do use the instructions for the Lee dies. I was just more interested in what those who seat and crimp in one step use. Since I only use Lee dies, it may only apply to people who use those dies. Not necessarily a newbie at this, but not an old hand at it either, have loaded just over 25,000 rounds, I'm sure many of you are well over 100,000 rounds. Thanks for the responses .

 

[Walkalong]

https://www.thehighroad.org/index.p...-and-crimp-in-two-stages.623417/#post-7699828

https://www.thehighroad.org/index.php?threads/universal-clays-and-357.511309/#post-6354182

 

[sparkyv]

I also eyeball. Seems to me that for some, crimping gets unnecessarily overcomplicated.

just compare a factory round to yours and adjust accordingly. Should keep you in the ball park.

I too, crimp "by eye" meaning I look at the crimp and determine if it's the correct crimp for the load, the bullet, and the use.

Me too. Lee crimp dies work exceedingly well for me. The pistol collet crimp die is quite interesting.

I have been reloading for quite a while and I still separate the seating and crimping steps. Very early on I tried to combine the process, but getting the adjustments "just right" was a pain and I felt I had more control on both steps when done separately.

 

[Walkalong]

I use magnification to help my old eyes.

 

[tightgroup tiger]

I'm curious as to how much of an extra turn you use on your die for the crimp?

I won't seat and crimp in one step with revolver rounds unless my cases are all trimmed to the same length. It's almost impossible to get consistent roll crimps with out trimming.

With my loads if I'm roll crimping, the amount of crimp I use is based on the kind of loads I'm making. Practice loads, just enough crimp to straighten the flare out, for hunting loads, I use a lot more.
I can't generalize how much crimp I use for all my loads because I load for a lot of different purposes.

 

[Walkalong]

125 Gr bullet seated and crimped in one step with a Hornady seater.

 

[Walkalong]

Seated and crimped (Heavy Taper) in two separate steps, and would be impossible in one step.

 

[.38 Special]

I seat and crimp in one step. I judge by eye. Fast powders and light loads get a light crimp, to maximise case life. Slow powders for heavy Magnum loads get a hard crimp. There may have been a time when I put more thought and effort into the matter, but if so I have forgotten it.

 

[.38 Special]

Also, Walkalong seems to know his business.

 

[film495]

I don't use that set of dies, but I can say I always have things work out the best following the directions that came with the die.