Author Topic: TO CRIMP OR NOT TO CRIMP! that is the question (Read 637 times)

mstake · « **on:** February 23, 2005, 01:36:04 AM »

i just ordered my 375 winchester barrel for encore and i was wondering do any of you guys crimp? i have read that the 44 and 357 are crimped not only for recoil but also to help with pressure in powders like H110 and lilgun. some have said that they got better groups when they played around with heavy or light crimps. i no in some cases that crimping may help to even up the pressure but is it something i should try with the 375winny? so what do you guys thinks. should i crimp or not! for now i am loading 200gr sierras with imr4198

PA-Joe · « **Reply #1 on:** February 23, 2005, 01:44:29 AM »

T/Cs tend to have long throats so a little crimping will help produce a consistent pressure. Generally with single shots you don't have to crimp. It also depends on how you will be carrying the rounds in the field. If not crimped and you push down on the tips, the COL will change.

Bug · « **Reply #2 on:** February 23, 2005, 05:14:00 AM »

PA Joe hit the nail. If you can push the bullet into the case with firm pressure on a bench, then I'd recommend a crimp. But, by trying with no crimp, light crimp, and heavy crimp is the only way I know to find out which will give the best accuracy.

Redhawk1 · « **Reply #3 on:** February 23, 2005, 05:23:51 AM »

For the 375 winchester I would not use a crimp in a single shot. I do not think it is needed.

jeff223 · « **Reply #4 on:** February 23, 2005, 06:10:22 AM »

i dont crimp for anything. i reload for.223,6.5x55swede,270,30-30,30-06,35whelenAI,357mag and 357max.i always wondered about this crimp thing but accuarcy has been very good for all the guns i load for.when i reload 357max ammo i just use two of the dies from the three die set.i full length size,then i chamfer the brass with a chamfer tool,then i prime the case,add powder,then i seat the bullet just off the lands.i have only loaded jacketed bullets for the max,no cast bullets.there is no way you can push the bullets deeper into the case with your fingers or by pushing on a bench.

375 brass is tough stuff and i dont see any need for a crimp.i would start off by not crimping and seat bullets just off the lands.if it doesnt work out for you then try crimping.

good luck

Bullseye · « **Reply #5 on:** February 23, 2005, 06:35:25 AM »

I have seen this debate before with straight wall rifle and pistol cases. My question is how do you get away without some sort of crimp if you bell the case mouth with the expander die.

1. Do you crimp just enough to straighten the case back out without a crimp.

2. Do you just run the expander in the case without belling the case mouth. If you do this will the bullets start and seat without messing up the case?

I crimp for my 375, always figured that way I was sure of getting rid of the bell on the case, the loads shoot good and the crimp does not hurt anything.

HL · « **Reply #6 on:** February 23, 2005, 07:39:32 AM »

I just run mine in to the crimping die just enough to straighten the case. No crimp.

Just need to make sure all brass is trimmed to the same length so you get a consistent straight wall without crimping, which would occur if any of the brass is stretched longer than the rest.

jeff223 · « **Reply #7 on:** February 23, 2005, 07:54:18 AM »

i dont use the expander die at all.i just chamfer the mouth of the brass just like you do on the rifle brass.
maybe im missing the boat here?i dont know for sure.if those of you out there with knowledge greater than mine concerning handloading PLEASE POST ON THIS SUBJECT

this is a good topic for sure

Redhawk1 · « **Reply #8 on:** February 23, 2005, 12:52:52 PM »

jeff223, if you shot a 454 casull or 500 MAG in a revolver, a crimp is a must. The bullet could work forward enough to jam the gun up and even enough for the bullet to be push out of the case from the recoil and you could lodge a bullet in between the cylinder and barrel.

jeff223 · « **Reply #9 on:** February 23, 2005, 02:37:30 PM »

thanks Redhawk1.
i should of stated i load and shoot single shot rifles and i shoot a contender pistol.i do have a couple of bolt actions as well but i dont even crimp for them.i dont own a revolver of any kind so i dont have to worry about the bullets coming out into the cylinder.you are correct about the need of crimped bullets in the heavy recoiling guns

Steve P · « **Reply #10 on:** February 23, 2005, 03:51:49 PM »

You crimp or don't crimp as you please. Your Contender barrel don't know the difference. Your target will, by the spread of the holes in it. If you are plinking and shooting cans, why bother? It just takes extra time anyway! :roll:

As for me, I crimp. With some rounds, taper AND roll. Why? Because a half scale chicken at 200 meters is hard to see, let alone hit. I want my ammo as accurate as possible. Does it cut my groups in half? Probably not. Does it give me perfect scores every time. NO....I wish. But, I seldom get the fliers I used to.....you know the one that suddenly missed the paper. The one that made a 4" group 6".

I check my brass, trim it to length, seat the bullet in one step, use a slight taper crimp to confirm bullet centered, then roll crimp if needed. I don't seat and crimp at the same time. It doesn't work. No, it doesn't. Don't argue....... :-)

Good luck with the method you choose. It will work, no matter what the choice. But the ends may not match the expectation...... :wink:

Steve

flyfisher · « **Reply #11 on:** February 25, 2005, 09:20:41 AM »

The only crimping that I do is a roll crimp on my .357 Mag shells for my revolvers. Any other shells I do no crimping. I also own a .375 Win barrel for my Contender, and I have never crimped a shell for it. Steve P is right, however. From everyone I've talked to and from everything I've ever read, crimping can yield consistent pressures, which nearly always equates to better accuracy. Crimping also can yield higher pressures (depending on the amount of crimp). I imagine that the pressures wouldn't be so high as to damage a barrel, but the high pressure may not yield superior accuracy. I experimented with the crimp on my .357 Mag revolver ammo, and found that a slight crimp, not a super tight crimp, yielded the best of both worlds. I am certainly not an expert on the subject, but that's about the extent to what I know and have heard.

jeff223 · « **Reply #12 on:** February 25, 2005, 11:42:29 AM »

Steve P may be right and he may be wrong.your group size will tell the tale like he says.the Contender is like a rifle as far as i am concerned and i reload ammo for it just like a rifle.if a person is happy with the results of their handloads than why change?if you seat just off the lands with your bullet you will have consistant start pressure.

Racepres · « **Reply #13 on:** February 25, 2005, 01:44:49 PM »

Roll crimps for me on any straight wall case. Bottlenecks either get a lee factory crimp or nothing.....375 Win?? I probably would start by not crimping for the contender. If you are trying to squeeze the last tenth out of er ... Lee Factory Crimp.... $0.02 ..Marty

jgalar · « **Reply #14 on:** February 25, 2005, 05:32:49 PM »

I don't think crimping will help if you can seat the bullet to the optimal distance from the rifling. Where crimping may help is when you have a long throat and can't seat your bullets out far enough. Where crimping does help is when you have multiple rifles in the same caliber and you don't want to load specific loads for each gun. Revolver loads must be crimped and autoloading pistols I just crimp enough to straighten out the mouth of the case.