do you have to crimp

25 July 2003, 14:42

hi all

i am about to do some testing with a sierra game king in 223. it has a crannular (sp) and i was wondering if you have to crimp. if i was going hunting with this round i would probably crimp but since im gonna be shooting of a rest with these i think that i shouldnt have to.

thanks
lojack

25 July 2003, 15:20

Ol` Joe

What type of rifle are you loading for? Semi autos should probably have a crimp to prevent bullet movement during feeding, but other than that, No you don`t have to crimp.

25 July 2003, 18:07

rootbeer

Crimping, besides serving to disallow bullet movement under recoil, also serves to allow an initial pressure to build behind the bullet, thus in essence making the bullet "squirt" from the case mouth in those scant milliseconds after powder ignition. It tends to give more consistent, predictable, repeatable starting pressures if done consistently. I crimp everything I reload because I like to "finish" the job and a good crimp looks nice.

26 July 2003, 08:22

lojack

well it is for a remmy 700. yes a bolt.

27 July 2003, 03:18

<eldeguello>

A good crimp looks nice, but does absolutely nothing for the performance of your ammo! Show me a benchrest competitor who crimps his super-accurate loads!! It als tends to shorten the life of your cases by overworking the case mouth, causing splits to occur sooner. I never crimp any rifle ammo any more, no matter what kind of gun I'm shooting it in, relying on use of an undersize expander button to get a good grip on bullets, if necessary, and a case full of powder to keep bullets from receding into the case neck. A 100% loading density is generally more accurate, anyway. However, crimp is absolutely necessary in revolver ammo, since a slight forward movement of just one bullet can tie up the gun, and give you a helluva fit trying to clear it!! [Big Grin]

27 July 2003, 05:03

Magnum Mike

The crimp can actually deform the bullet causing problems with accuracy. I NEVER crimp rifle cartridges unless it is going in a semiatuo. I DO crimp all the magnum revolver rounds to aide consistant start pressure.

27 July 2003, 05:39

packrat

I would not bother when using a bolt gun.

27 July 2003, 08:25

rootbeer

MSSmagnum,
That bolt-action pistol is intriguing. Is that stock offered in a .223 Rem and for a lefty bolt for those of us who hold our pistols and revolvers in our right hand? Who makes it? Where can I see one on el webbo? What is the eye relief on that scope?

[ 07-26-2003, 23:26: Message edited by: rootbeer ]

27 July 2003, 16:28

LE270

The answer to your question is no, you don't have to crimp, especially for loads to be used only for target shooting, but doing so may improve your accuracy. See Saeed's tests as given elsewhere in accuratereloading -- those tests suggest that there is a small but measurable increase in accuracy with at least some calibers when using the Lee Factory Crimp die. My own results tend to confirm that conclusion, and I now usually crimp all my centerfire rifle loads.

[ 07-27-2003, 22:24: Message edited by: LE270 ]

28 July 2003, 06:16

MADISON

I have loaded for the 270, 20-06, 45-70, 222, 223 and 22 Hornet. I have never crimped them.
Some bullet manufacturers do not make bullets with canalures. So do not worry about crimping.

28 July 2003, 06:40

LE270

quote:
Originally posted by MADISON:
Some bullet manufacturers do not make bullets with canalures. So do not worry about crimping.

Your claim that some manufacturers make bullets without cannelures is true, but that's irrelevant to whether crimping with the Lee Factory Crimp Die should be done in order to improve the accuracy of your loads. The Lee tool works with any bullet, whether or not it has a cannelure, and whether or not, if it has a cannelure, you actually crimp on the cannelure or elsewhere.

[ 07-27-2003, 21:45: Message edited by: LE270 ]

28 July 2003, 06:49

stubblejumper

Some mamufacturers have even posted warnings that crimping their non cannelured bullets will decrease accuracy.

28 July 2003, 07:04

LE270

quote:
Originally posted by stubblejumper:
Some mamufacturers have even posted warnings that crimping their non cannelured bullets will decrease accuracy.

Maybe so.

But I suggest that everyone go to the FAQ section of accuratereloading, and then click on the section on the effects of crimping on accuracy and consistency of velocity. Saeed did tests on three calibers: a .223, a .243, and a .308 using Nosler Ballistic Tip, Berger, and Sierra Matchking bullets, all of them without a cannelure. Saeed says that he began as a skeptic, but that he found an increase of about 10% in accuracy. That's not a huge increase, but it is a significant and measurable one.

Your results with your loads in your rifle may differ. But I think that no one should dismiss these results unless he has done his own tests, using loads that differ only in having and not having a crimp. Also, I think that the only crimp that should be considered here is the one made with the Lee Factory Crimp dies, as their crimping method differs a lot from that used by standard seating dies when those dies are used to make a crimp.

[ 07-27-2003, 22:13: Message edited by: LE270 ]

28 July 2003, 10:46

Atkinson

You can go either way with a crimp, there are two schools of thought and theory on this and no one knows who is correct...I think it depends on the gun....

Personally I do not crimp any cartridges other than some big bores to hold the bullets against recoil...

IMO one cannot crimp consistantly as our case trimmers are simply not that accurate, thus you loose consistency....an uncrimped case is more consistant as most bench resters will attest to..and my guns certainly shoot well without crimping, so I see no need, but I am primarily a hunter and my requirments are less than say a bench rest advocate..still most of my guns will shoot an inch or better or they go down the road......

29 July 2003, 09:59

LE270

quote:
Originally posted by Atkinson:
IMO one cannot crimp consistantly as our case trimmers are simply not that accurate, thus you loose consistency.

Mr. Atkinson:

Have you ever tried using the Lee case trimming system and the Lee Factory Crimp dies? I suspect that you have not done so, or you would have a different opinion.

29 July 2003, 14:49

Magnum Mike

quote:
Originally posted by rootbeer:
MSSmagnum,
That bolt-action pistol is intriguing. Is that stock offered in a .223 Rem and for a lefty bolt for those of us who hold our pistols and revolvers in our right hand? Who makes it? Where can I see one on el webbo? What is the eye relief on that scope?

Remington made the XP-100R in 223 as well as a few other calibers. The bolt handle on them is on the right side as it truly is nothing more than a Model 7 with a short tube. The stock is made by McMillan Brothers. I sent it to them and had the "right handed" thumbrest removed as i am a lefty. The stock is just a synthetic without any type of bedding from the "Custom Shop". [Roll Eyes]

I will be sending it to Virgin Valley to have it pillar bedded this winter. Right now it is too busy wackin woodchucks! [Big Grin]

The scope is a Burris 10x in that pic but it now wears a Burris 3x-12xAO matte that matches the rst of the gun. Eye relief on these scopes runs in the 9-12" range at top end and around 12-24" at the lowest settings. I wacked a chuck at 388 paces this summer with that rig, me longest handgun kill yet. Never needed anymore scope! [Big Grin]