Neck Crimping Advice

[BergerBoy]

Hello,
I just recently spoke with my father and was talked into purchasing a neck crimper for my 300WM. I never have used one on my rifles only pistol reloads.
I noticed some of the bullets seemed to be a lil more loose than what I feel comfortable with even though groups were good and my ES was 11 fps or less.
Will you give me your advice/experience with neck crimping, pros cons etc....
Thanks for your time

 

[Canadian Bushman]

I dont crimp. It deforms bullets.

Ive always just relied on neck tension to keep things together.

 

[gohring3006]

I only use a very light crimp on my AR loads. I never crimped any of my bolt gun loads. If I was going to, I would make sure all of my brass was the same length and I would anneal often. I wouldn't be surprised to see your ES vary. But maybe not....
If you feel your neck tension is not what you like, Try annealing its probably lost its spring back ability.

 

[Corey Schwanz]

For most bolt action rifles, the neck tension from the sizing die should be enough to hold the bullet in place depending on the die and the brass thickness. I only crimp my AR rounds as my full length sizing die isn't quite enough to hold the bullet tight when it chambers. If you have a bushing type die, the easy solution is get a smaller bushing to size down the necks a bit more.

 

[Bigeclipse]

Hello,
I just recently spoke with my father and was talked into purchasing a neck crimper for my 300WM. I never have used one on my rifles only pistol reloads.
I noticed some of the bullets seemed to be a lil more loose than what I feel comfortable with even though groups were good and my ES was 11 fps or less.
Will you give me your advice/experience with neck crimping, pros cons etc....
Thanks for your time

I agree with others...I'd avoid neck crimping. What you can do to put your mind at ease is measure some of your rounds prior to loading into your rifle. Make sure and measure to ogive and not tip. Mark these rounds with a sharpie so you know which ones are which. Then go fire your rifle. Do not chamber the marked bullets. Keep loading your chamber with a new round that isn't measured. Fire like 4 shots. Then remeasure the rounds you measured before and compare. If they did not change in length then you are fine. Again...do not measure the tip because yes the tip could jam against the front of the mag and deform but the bullet should stay seated properly and this slight deformation shouldn't impact accuracy much at all as long as your ogive measurement is fine. If the bullets are indeed moving in your cases then your neck tension is off which you should fix by replacing your die. I'd never crimp a long range rifle...too much risk in deformity the bullets

 

[mountainman56]

I have had good luck crimping and continue to do so on the several 300 WM and 300 RUM I am loading for now. Started out as mostly piece of mind for handloads going on expensive hunts. I don't crimp when working up a load. When I get the recipe I'm happy with I will check crimped loads against uncrimped. I have found no difference in accuracy, in fact one lightweight custom 300 WM I load for, shooting 200gr LRX bullets the accuracy actually improved. I have no explanation for this.

 

[Bigeclipse]

I have had good luck crimping and continue to do so on the several 300 WM and 300 RUM I am loading for now. Started out as mostly piece of mind for handloads going on expensive hunts. I don't crimp when working up a load. When I get the recipe I'm happy with I will check crimped loads against uncrimped. I have found no difference in accuracy, in fact one lightweight custom 300 WM I load for, shooting 200gr LRX bullets the accuracy actually improved. I have no explanation for this.

That'S cool crimping works for you. I've never had a bullet slip but I've only loaded for one magnum rifle...my 7mm rem mag so I've never worried about it.

 

[Bill Johnson]

Well, you don't want to even attempt crimping if the bullet doesn't have a cannalure.

I use Redding bushing dies and control neck tension instead.

Crimping or increased neck tension can improve accuracy by delaying bullet release, allowing the powder to ignite better.

 

[mountainman56]

Well, you don't want to even attempt crimping if the bullet doesn't have a cannalure.

I use Redding bushing dies and control neck tension instead.

Crimping or increased neck tension can improve accuracy by delaying bullet release, allowing the powder to ignite better.

So........crimping can improve accuracy but you shouldn't do it without a cannelure? I beg to differ. I'm not talking about crimping with your seating die but with a dedicated crimping die where you can control the amount of pressure.

 

[savagekindaguy]

Check out a Lee Factory Crimp die. I use them on my .308 and .223. Not sure if the 7.62x54 Mosin has a Factory Crimp die but I think it does. I haven't loaded any of them yet so I am just guessing. Lee states the Factory Crimp Dies are tough enough to crimp properly even if the bullet does not have a cannelure. I crimp copper solids as well as jacketed bullets that have no cannelure. It does not take a lot of crimp pressure to secure the bullet...even if the bullet has no cannelure.

https://fsreloading.com/lee-precision-factory-crimp-die-.300-winchester-magnum-90825.html

 

[Bill Johnson]

So........crimping can improve accuracy but you shouldn't do it without a cannelure? I beg to differ. I'm not talking about crimping with your seating die but with a dedicated crimping die where you can control the amount of pressure.

Nice sharpshooting, buddy.

To physically squeeze, for instance, .024" in wall thickness and .308" in bullet into a roll die, where do you think the material goes as it enters the die section that is less than .332?



Granted, that's an extreme example but you get the idea. The other thing that happens is neck walls are extruded at the mouth, leading to early neck cracks.

Yes, people do crimp non- cannelure bullets. It's just not the best way, or the recommended way to address the OP's issue.

 

[BergerBoy]

Thank you guys for all the input.

I can see how it would lessen brass life. Maybe I'll load a few and see happens but after listening to the majority I leaning toward not crimping.

Thanks again.

 

[Garycrow]

The only way you want to crimp is with the lee factory crimp die. It crimps from the side and you can adjust the amount of crimp very precisely. A light crimp will do no damage but will still hold the bullet in place, you don't have to have a cannelure. If you adjust the die to maximum crimp it can dent the bullets as shown above, but a light crimp won't.

Depending upon the round and magazine setup some heavy kicking rifles will seat the bullet a bit deeper in the case for rounds in the magazine when it's shot. You usually can't tell it by looking at it, but if you measure it you'll see it happening. Neck tension is not enough on some rifles. I've got a .375 H&H that pushed a bullet almost completely inside the case after a few shots. I have lee factory crimp dies for all my heavy kickers.

 

[mountainman56]

The only way you want to crimp is with the lee factory crimp die. It crimps from the side and you can adjust the amount of crimp very precisely. A light crimp will do no damage but will still hold the bullet in place, you don't have to have a cannelure. If you adjust the die to maximum crimp it can dent the bullets as shown above, but a light crimp won't.

Depending upon the round and magazine setup some heavy kicking rifles will seat the bullet a bit deeper in the case for rounds in the magazine when it's shot. You usually can't tell it by looking at it, but if you measure it you'll see it happening. Neck tension is not enough on some rifles. I've got a .375 H&H that pushed a bullet almost completely inside the case after a few shots. I have lee factory crimp dies for all my heavy kickers.

There ya go. I should have specified the Lee factory crimp die which is what I use. For $30 or so they are certainly worth trying.