To Crimp or Not Crimp

ebueker · March 29, 2006, 05:06 PM

I am relatively new to reloading. I have been using TSXs and Nosler Balistic Tips with no crimp. Someone told me he always crimps no matter the bullet style, even smooth bullets like BTs. Am I wrong not to crimp?

Dave R · March 29, 2006, 06:16 PM

What kind of rifle and what cartridge? In general terms...

Crimping is seldom done with bolt-action rifles and single-shots. No need unless its a real kicker. And crimping seems to reduce accuracy.

Crimping is mandatory for tube-fed lever actions, to make sure you don't get bullet set-back from the pessure in the tube, and from recoil.

ebueker · March 29, 2006, 06:54 PM

Rifle is 300 mag and 280 Rem. Remington M 700 and Ruger M77 Mk II

kingudaroad · March 29, 2006, 08:09 PM

Every Nosler BT I've ever seen has no crimping cannelure,don't know about TSX, but you surely don't want to crimp into the jacket.

From my limited education there is no crimp needed in a bottle neck cartridge fired out of a bolt action rifle. Good, solid, tight, even,neck tension is all that's needed.

No crimp for me thank you

steve4102 · March 29, 2006, 11:13 PM

If you are going to crimp, use the Lee Factory Crimp Die. It will put a nice crimp on any bullet with or without a cannelure(groove). The Lee Factory Crimp Die can and does Increase accuracy not decrease it. Here is some interesting reading. http://www.accuratereloading.com/crimping.html

http://www.leeprecision.com/cgi/cata...ies-crimp.html

http://www.midwayusa.com/eproductpag...eitemid=586092

kidcoltoutlaw · March 30, 2006, 12:15 AM

In the bench rest game accuracy is all that matters and no one crimps,

Thanks,Keith

Tim R · March 30, 2006, 12:26 AM

No crimps for service rifle/High Power as well.

steve4102 · March 30, 2006, 12:51 AM

Quote:

In the bench rest game accuracy is all that matters and no one crimps,

In the bench rest game, no one is shooting a Ruger M77 or Rem 700 either. They are all shooting custom this and custom that. Does your comment mean that we are not allowed to try different things that may or may not improve accuracy in our cheap-piece of sit-off the rack-non custom rifles because the bench rest shooters don't do it. I think NOT. I will try anything I can to find the most accurate load for my rifles.
Don't knock it until you have tried it!!!

Waffen · March 30, 2006, 01:47 AM

I agree with Steve here, I have never tried crimping my bolt rifle loads but it's worth a shot. If it has a cannelure to crimp into great, roll crip that thing, if not taper crip it. I have read over that info on accuratereloading quite a bit for the past few months and have been thinking I would give it a try.

I would think crimping would really just give you reliable neck tension with every round and thats whey they are seeing an increase in accuracy. It could also help bullets from jumping if you shoot a heavy recoiling gun with rounds in the magazine.

Just a thought

DAVID NANCARROW · March 30, 2006, 01:55 AM

Unless you are willing to go through the trouble of neck turning your brass, wouldn't the variable thickness of the neck cause uneven bullet pull from the case at ignition?

Leftoverdj · March 30, 2006, 02:36 AM

Quote:

I think NOT. I will try anything I can to find the most accurate load for my rifles.
Don't knock it until you have tried it!!!

Go right ahead if you want to use up barrel life on remote possibilities.

steve4102 · March 30, 2006, 08:45 AM

Quote:

Go right ahead if you want to use up barrel life on remote possibilities.

Interesting comment. Lets talk about "Remote Possibilities" that "Use up Barrel Life".
Here is some of the remote possibilities that many handloaders do to improve accuracy. Or in levtoverdj's case just waist barrel life.
Change brass manufacturer,
Change Primer type and primer manufacturer,
Deburr the flash hole,
Uniform the primer pocket,
Neck turn the brass,
Inside neck ream the brass,
Weigh and sort brass,
Switch powder,
Switch bullet weight
Switch bullet type,
Switch bullet brand
Makem longer
Makem shorter
And on and on and on we go.

But, remember the accuracy potential of any of these techniques is remote and may or may not improve accuracy so consider then a "Waist of Barrel Life".

dakotashooter2 · March 30, 2006, 08:56 AM

Quote:

"Waist of Barrel Life".

I guess we should just hang them on the wall and look at them then!

30Cal · March 30, 2006, 11:26 AM

Crimp is not a slam dunk accuracy improvement. I've messed with it enough to know that goodly portion of the time, it's going to work against you, depending on the rifle.

Superhornet · March 30, 2006, 11:57 AM

Leftoverdj-----and your guide for crimping/not crimping??

Leftoverdj · March 30, 2006, 12:51 PM

In hunting grade rifles, I do not crimp for guns without a tube magazine with the exception of slow-for-cartridge powders in straightwall cases and autoloaders. I tried crimping long enough to satisfy myself that it is usually harmful to accuracy.

I also tried weighing, sorting, neckturning, etc., and satisfied myself that, in my guns, it's a waste of time. So is weighing each powder charge, with the exception of a few coarse powders.

In my experience, the most important accuracy factors are, in order, bullet selection, powder selection, charge weight, and seating depth. That's enough variables for me to be messing with most of the time. I skip the seating depth when I am limited by magazine length. Rarely, I change primers, but only with loads that are already very promising.

Even with my abbreviated development process, I generally fire 500-1000 shots before settling on a load, and that number goes up significantly when I want both a varmint load and a deer load for the same rifle. Bear in mind that the process may need to be repeated when one of the components is no longer available and the accurate barrel life of the hot .25s I favor is 3500-5000 rounds.

These days, most of my shooting is done with cast bullets and moderate loads. Barrel life is virtually unlimited with those.

marks655 · March 30, 2006, 02:07 PM

Crimping can aid accuracy in some instances. Certainly in autoloaders and tube-feed rifles.

The exception might be AR15's which don't seem to benefit from crimping.

One advantage to crimping is that neck 'tension' is more consistent, and of course, bullet depth is not influenced by chambering (bullet seating being affected by hitting the feed ramp, etc.)

I don't believe crimping has an adverse effect on accuracy. Any effect it may have on the bullet (marring the bullet as it leaves the case) is minor compared to rifling, etc.

One other advantage in hunting rifles is if you load into the lands. Crimping prevents the possibility of pulling a bullet when unloading a round - which is at least a major inconvienence when in the field.

Overall, I see some advantages and few, if any, disadvantages to crimping.

Superhornet · March 30, 2006, 03:04 PM

Leftoverdj----good answer.......I to use a lot of cast, but normally in revolver...and some 45-70 loads...Do you have an NEF in 7.62X39 yet ???

Leftoverdj · March 30, 2006, 04:05 PM

SuperHornet, I bought a CZ 527 in 7.62x39 not long before the NEF came out. I might eventually pick up an NEF, but I haven't yet. The 7.62x39 is an extremely cast bullet friendly cartridge, and the CZ is a superb rifle.

steve4102 · March 30, 2006, 05:56 PM

http://forums.accuratereloading.com/...1862#580101862

Some more interesting reading.

Superhornet · March 31, 2006, 07:30 AM

Steve4102---that is good data and I have used the Lee Factory Crimp die on many jacketed bullets....that also includes bullets that do not have a cannalure....I shoot mainly the NEF SB2 SS rifles from .22 Hornet through 45-70 and just about everything in between...I did get accuracy improvement on many loadings.....The crimp would tend to allow the pressure cylcle to reach the same level before the bullet starts to move...and thusly improve the characteristics of the handloads...Loaded for a 300WSM, Savage rifle..(my friends gun)......using 180 grain Accubonds. All loadings crimped...accounted for 5 whitetail, one Elk and one buffaloe......The Accubond does not have a Cannalure..the bullet was very accurate..1" at 100yards...

March 29, 2006, 05:06 PM	#1
ebueker Member Join Date: March 17, 2006 Posts: 15	To Crimp or Not Crimp I am relatively new to reloading. I have been using TSXs and Nosler Balistic Tips with no crimp. Someone told me he always crimps no matter the bullet style, even smooth bullets like BTs. Am I wrong not to crimp?

March 29, 2006, 06:16 PM	#2
Dave R Senior Member Join Date: January 7, 2000 Location: Idaho Posts: 6,073	What kind of rifle and what cartridge? In general terms... Crimping is seldom done with bolt-action rifles and single-shots. No need unless its a real kicker. And crimping seems to reduce accuracy. Crimping is mandatory for tube-fed lever actions, to make sure you don't get bullet set-back from the pessure in the tube, and from recoil. __________________ I am Pro-Rights (on gun issues).

March 30, 2006, 12:15 AM	#6
kidcoltoutlaw Senior Member Join Date: April 13, 2000 Location: bluefield Posts: 735	I think the crimp and accuracy is bull In the bench rest game accuracy is all that matters and no one crimps, Thanks,Keith __________________ It's not just a gun it's the symbol of freedom

March 30, 2006, 12:26 AM	#7
Tim R Senior Member Join Date: November 30, 2004 Location: God's side of Washington State Posts: 1,601	No crimps for service rifle/High Power as well. __________________ God Bless our Troops especially our Snipers.

March 30, 2006, 02:07 PM	#17
marks655 Senior Member Join Date: January 21, 2006 Location: Ohio Posts: 363	some good and no bad Crimping can aid accuracy in some instances. Certainly in autoloaders and tube-feed rifles. The exception might be AR15's which don't seem to benefit from crimping. One advantage to crimping is that neck 'tension' is more consistent, and of course, bullet depth is not influenced by chambering (bullet seating being affected by hitting the feed ramp, etc.) I don't believe crimping has an adverse effect on accuracy. Any effect it may have on the bullet (marring the bullet as it leaves the case) is minor compared to rifling, etc. One other advantage in hunting rifles is if you load into the lands. Crimping prevents the possibility of pulling a bullet when unloading a round - which is at least a major inconvienence when in the field. Overall, I see some advantages and few, if any, disadvantages to crimping.

March 29, 2006, 06:54 PM	#3
ebueker Member Join Date: March 17, 2006 Posts: 15	Rifle is 300 mag and 280 Rem. Remington M 700 and Ruger M77 Mk II

March 29, 2006, 08:09 PM	#4
kingudaroad Senior Member Join Date: March 11, 2005 Location: austin Posts: 735	Every Nosler BT I've ever seen has no crimping cannelure,don't know about TSX, but you surely don't want to crimp into the jacket. From my limited education there is no crimp needed in a bottle neck cartridge fired out of a bolt action rifle. Good, solid, tight, even,neck tension is all that's needed. No crimp for me thank you

March 29, 2006, 11:13 PM	#5
steve4102 Senior Member Join Date: December 23, 2005 Location: Minnesota Posts: 2,955	If you are going to crimp, use the Lee Factory Crimp Die. It will put a nice crimp on any bullet with or without a cannelure(groove). The Lee Factory Crimp Die can and does Increase accuracy not decrease it. Here is some interesting reading. http://www.accuratereloading.com/crimping.html http://www.leeprecision.com/cgi/cata...ies-crimp.html http://www.midwayusa.com/eproductpag...eitemid=586092

March 30, 2006, 01:47 AM	#9
Waffen Member Join Date: February 3, 2002 Location: Austin Posts: 85	I agree with Steve here, I have never tried crimping my bolt rifle loads but it's worth a shot. If it has a cannelure to crimp into great, roll crip that thing, if not taper crip it. I have read over that info on accuratereloading quite a bit for the past few months and have been thinking I would give it a try. I would think crimping would really just give you reliable neck tension with every round and thats whey they are seeing an increase in accuracy. It could also help bullets from jumping if you shoot a heavy recoiling gun with rounds in the magazine. Just a thought

March 30, 2006, 01:55 AM	#10
DAVID NANCARROW Senior Member Join Date: November 5, 2000 Location: Wyoming Posts: 1,761	Unless you are willing to go through the trouble of neck turning your brass, wouldn't the variable thickness of the neck cause uneven bullet pull from the case at ignition?

March 30, 2006, 11:26 AM	#14
30Cal Senior Member Join Date: December 3, 2002 Posts: 1,264	Crimp is not a slam dunk accuracy improvement. I've messed with it enough to know that goodly portion of the time, it's going to work against you, depending on the rifle.

March 30, 2006, 11:57 AM	#15
Superhornet Senior Member Join Date: March 24, 2005 Location: florida Posts: 292	Leftoverdj-----and your guide for crimping/not crimping??

March 30, 2006, 12:51 PM	#16
Leftoverdj Senior Member Join Date: October 15, 2004 Posts: 934	In hunting grade rifles, I do not crimp for guns without a tube magazine with the exception of slow-for-cartridge powders in straightwall cases and autoloaders. I tried crimping long enough to satisfy myself that it is usually harmful to accuracy. I also tried weighing, sorting, neckturning, etc., and satisfied myself that, in my guns, it's a waste of time. So is weighing each powder charge, with the exception of a few coarse powders. In my experience, the most important accuracy factors are, in order, bullet selection, powder selection, charge weight, and seating depth. That's enough variables for me to be messing with most of the time. I skip the seating depth when I am limited by magazine length. Rarely, I change primers, but only with loads that are already very promising. Even with my abbreviated development process, I generally fire 500-1000 shots before settling on a load, and that number goes up significantly when I want both a varmint load and a deer load for the same rifle. Bear in mind that the process may need to be repeated when one of the components is no longer available and the accurate barrel life of the hot .25s I favor is 3500-5000 rounds. These days, most of my shooting is done with cast bullets and moderate loads. Barrel life is virtually unlimited with those.

March 30, 2006, 03:04 PM	#18
Superhornet Senior Member Join Date: March 24, 2005 Location: florida Posts: 292	Leftoverdj----good answer.......I to use a lot of cast, but normally in revolver...and some 45-70 loads...Do you have an NEF in 7.62X39 yet ???

March 30, 2006, 04:05 PM	#19
Leftoverdj Senior Member Join Date: October 15, 2004 Posts: 934	SuperHornet, I bought a CZ 527 in 7.62x39 not long before the NEF came out. I might eventually pick up an NEF, but I haven't yet. The 7.62x39 is an extremely cast bullet friendly cartridge, and the CZ is a superb rifle.

March 30, 2006, 05:56 PM	#20
steve4102 Senior Member Join Date: December 23, 2005 Location: Minnesota Posts: 2,955	http://forums.accuratereloading.com/...1862#580101862 Some more interesting reading.

March 31, 2006, 07:30 AM	#21
Superhornet Senior Member Join Date: March 24, 2005 Location: florida Posts: 292	Steve4102---that is good data and I have used the Lee Factory Crimp die on many jacketed bullets....that also includes bullets that do not have a cannalure....I shoot mainly the NEF SB2 SS rifles from .22 Hornet through 45-70 and just about everything in between...I did get accuracy improvement on many loadings.....The crimp would tend to allow the pressure cylcle to reach the same level before the bullet starts to move...and thusly improve the characteristics of the handloads...Loaded for a 300WSM, Savage rifle..(my friends gun)......using 180 grain Accubonds. All loadings crimped...accounted for 5 whitetail, one Elk and one buffaloe......The Accubond does not have a Cannalure..the bullet was very accurate..1" at 100yards...