The Firing Line Forums

Go Back   The Firing Line Forums > The Skunkworks > Handloading, Reloading, and Bullet Casting

Reply
 
Thread Tools
Old February 23, 2012, 06:51 PM   #26
89blazin
Senior Member
 
Join Date: March 13, 2009
Posts: 107
crimping rifle bullets

I use Lee and crimp all my rifle reloads, 5.56, 7.62x39, 7.62x51, 30-30, 270 Win, 30-06, and 7mm Rem Mag, both bullets with and without cannelures. Discovered decades ago that a little crimp helps accuracy. Also discovered that too much crimp can hurt accuracy. To me crimping is a process one has to acquire the feel for. Sometimes I'll even adjust the Lee crimp die a little for one bullet out of a batch I'm reloading, because the pressure required to complete the crimp is excessive or too light. Crimping rifle bullets for use in a non-tube mag is a personal preference thing, kinda like shaving...some shave in direction with their whiskers, others shave against them...
89blazin is offline  
Old February 23, 2012, 07:04 PM   #27
Slamfire
Senior Member
 
Join Date: May 27, 2007
Posts: 4,010
Only crimp for tubular magazines and weapons with exceptionally high cyclic rates, and elephant guns.

Never crimp a match bullet.

Crimping always swages the soft inner core of a bullet and will deform the jacket at some crimp level. Like what a Lee Crimp die did to these 6.5 SMK’s.



Deforming the core of a bullet and deforming the jacket will change the center of gravity. As that bullet rotates, with a center of gravity now outside the center of rotation, this will add inaccuracy.

No one, and I mean no one, who is a good competitive shooter, be it across the course, long range, bench rest, crimps their bullets. Period. I have been squadded with National Champs, I have friends who are national champs. No one crimps match bullets. If there was the slightest, tiniest tiny advantage, everyone would crimp.
__________________
If I'm not shooting, I'm reloading.
Slamfire is offline  
Old February 23, 2012, 07:18 PM   #28
dacaur
Senior Member
 
Join Date: March 16, 2010
Posts: 733
Those were obviously WAY overcrimped, probably the reason they were pulled. When I pull my crimped .308 win bullets I cant even tell they have ever been loaded looking at them.

Match bullets..... Well, I guess if we all used match bullets, we wouldn't worry about crimping them....

But, since most of us dont use match bullets, I think things are probably different, based on the number of people who claim its increased their accuracy....

Basically, you just neatly proved my point from post 6. People that have used the FCD, like it, those who diss it, have not tried it

Is the FCD a crutch for poorly loaded bullets? Its insulting to even suggest, but even if it is, so what? I can get sub MOA groups by buying match bullets, or I can get the same groups with cheap bullets and a FCD.... The target doesnt know the difference, neither does anyone else but my wallet....
dacaur is offline  
Old February 23, 2012, 07:54 PM   #29
89blazin
Senior Member
 
Join Date: March 13, 2009
Posts: 107
Slamfire,

So the guys at Perry shooting rapid fire in the service rifle match using 7.62x51 M1As (one of the fastest cyclic rates around), do not crimp their SMKs ?

Last edited by 89blazin; February 23, 2012 at 08:02 PM.
89blazin is offline  
Old February 23, 2012, 10:03 PM   #30
tpcollins
Senior Member
 
Join Date: February 18, 2009
Location: SE Michigan
Posts: 443
Quote:
Tpcollins - I would think a "little crimp" might be ok versus something that digs into the bullet rather deep.

Quote:
Decaur - Those were obviously WAY overcrimped, probably the reason they were pulled.
I agree with Decaur and that was my point - I still think just a little crimp will work better than one that gouges the crap out of the bullet.
__________________
What direction did that last shot at Kennedy come from?
tpcollins is offline  
Old February 23, 2012, 11:16 PM   #31
Scimmia
Senior Member
 
Join Date: May 19, 2011
Location: Eastern IA
Posts: 428
So Slamfire, if I posted some pics of some cases damaged by a severely out of adjustment bushing neck sizing die, would you post over and over again about how they should never be used or do you just have some kind of vendetta against the collet crimp dies?

Quote:
Deforming the core of a bullet and deforming the jacket will change the center of gravity. As that bullet rotates, with a center of gravity now outside the center of rotation, this will add inaccuracy.
Even assuming the jacket is "deformed", it'll be deformed uniformly around the entire bullet, which will NOT change the center of gravity. Of course, if something is severely out of adjustment like in your picture, all bets are off.

Quote:
No one, and I mean no one, who is a good competitive shooter, be it across the course, long range, bench rest, crimps their bullets. Period. I have been squadded with National Champs, I have friends who are national champs. No one crimps match bullets. If there was the slightest, tiniest tiny advantage, everyone would crimp.
And if we were all using the exact same rifles and the exact same bullets as them, I might agree with you. Personally, I don't pay $2+ per bullet and shoot it out of a custom gun with a custom chamber.
Scimmia is offline  
Old February 24, 2012, 12:03 AM   #32
NESHOOTER
Senior Member
 
Join Date: October 16, 2009
Posts: 509
I crimp my all of my rounds rifle and pistol, I find it allows the the powder to burn more evenly just what ever miliseconds before the bullet leaves the case therefore I have a more consistent FPS equals better accuracy/grouping and I use the LEE collet FCD.
NESHOOTER is offline  
Old February 24, 2012, 04:54 AM   #33
Bamashooter
Senior Member
 
Join Date: March 12, 2010
Posts: 1,708
I crimp my .223 loads since its a semi auto. A very light crimp. Nothing that would deform a bullet, or the brass for that matter. I think it gives the brass a uniform grip on the bullet and I get more consistency round to round.
Bamashooter is offline  
Old February 24, 2012, 12:43 PM   #34
HJ857
Senior Member
 
Join Date: January 9, 2007
Location: haslett, mi
Posts: 334
Quote:
Even assuming the jacket is "deformed", it'll be deformed uniformly around the entire bullet, which will NOT change the center of gravity. Of course, if something is severely out of adjustment like in your picture, all bets are off.
I tend to agree with this. I don't see how a light crimp indentation from a FCD is substantially different than a factory cannelure.

Quote:
I crimp my all of my rounds rifle and pistol, I find it allows the the powder to burn more evenly just what ever miliseconds before the bullet leaves the case therefore I have a more consistent FPS equals better accuracy/grouping and I use the LEE collet FCD.
When developing loads I rely on experiences posted at Sniper's Hide, and for the rounds that I load, those guys largely agree with the crimp procedure.

Overall though, I don't think there's ever a magic formula for any given load. It has to be tested to determine if a crimp is helpful or detrimental for your rifle and load's performance.

Last edited by HJ857; February 24, 2012 at 12:48 PM.
HJ857 is offline  
Old February 24, 2012, 02:54 PM   #35
dacaur
Senior Member
 
Join Date: March 16, 2010
Posts: 733
Quote:
Even assuming the jacket is "deformed", it'll be deformed uniformly around the entire bullet, which will NOT change the center of gravity. Of course, if something is severely out of adjustment like in your picture, all bets are off.
Exactly... its not as if a bullet leaves the bore in perfect condition.. the core is squeezed and deformed by the rifling more than a properly adjusted crimp die deforms it.... But like the die, its doing it from all sides, so no harm is done to the bullets flight....
dacaur is offline  
Old February 24, 2012, 04:21 PM   #36
Bart B.
Senior Member
 
Join Date: February 15, 2009
Posts: 4,370
A lot of the posts in this thread crimps my style. Such is life.

Nobody shooting centerfire rifles winning matches and setting records ever crimps a bullet. Tests with rail guns fired in free recoil with the best of everything used to load shoot the very best match bullets into the tiniest groups possible......ever crimps a case mouth. It adds another (huge) variable to the ammo by causing large spreads in case neck tension on bullets.

Decades ago, military arsenals used to crimp .30-06 match ammo bullets in cases just like regular service rounds are made. 'Twas either Hatcher or Whelen that said they really shouldn't do that 'cause it hurts accuracy. So one arsenal ran a lot of match ammo with half the cases crimped with different amounts of case mouth curl and the other half had no crimp at all. Since then, all arsenal rifle match ammo's never been crimped. And the scores were better too.

Uncrimped ammo shot the most accurate. As ammo with crimp was tested, the more the crimp the more the test groups open up.

So......if anyone feels a need to crimp their centerfire rifle bullets (save those used in 35 caliber and larger monster mashers) for best accuracy.....think again. Your're doing something pretty attrocious with your hand/re-loading tools and/or processes that's masked by crimping in your bullets. Or, you just happened to shoot the tiniest few-shot groups with crimped ammo and thing its the best thing since dollar bills. Some will never understand. Others may do so and end up with uncrimped case mouths on ther bullets shooting them more accurate.
Bart B. is offline  
Old February 24, 2012, 04:56 PM   #37
Scharfschuetzer
Senior Member
 
Join Date: January 28, 2012
Location: Puget Sound
Posts: 293
I go along with that.

The military still crimps combat ammo, but that ammo uses bullets with a cannalure designed for that purpose. From WWII, bullets with a cannalure were used in M2 Ball, M62 Ball, M80 Ball in the 30 cals and the M193 and M855 rounds for the M16/M4 weapons.

For match and sniper ammo, the army has not bothered with a crimp and the bullets used in the more accurate rounds for match and sniper shooting have no cannalure. These rounds include the M72, M118, M118LR and the M852 rounds for the 30 cals and the 77 grain 5.56 round for the M16/M4 weapons.

I've shot all of the above rounds over my career as well as handloads duplicating or exceeding their performance. This has been done as both a member of military shooting teams and also in the field with the M21, M24 and Mk13 SWS rifles and the Browning 1919, M60, M240 and M249 machine guns. Each round performs as intended when used as intended. I'm glad that the combat rounds are crimped and I'm glad the accuracy rounds are not crimped.

Another point to make is that the big bullet manufacturers cannalure some bullets and leave others without a cannalure. The purpose of the bullet often decides if a bullet has the cannalure or not, just as with the army's ammo.

Examples:

Bullets intended for the tube magazine rifles all have a cannalure, even the new Hornady spirepoint design for the 30/30.

Bullets made for ball ammo duplication in service rifles have cannalures.

Bullets designed for maximum accuracy generally do not have a cannalure.

I could go on ad naseum, but you get my drift. I've not met any successful high power NM or long range competitors that crimp their ammo. Neck tension (about .003" below your bullet diameter) is sufficient for non-cannalured bullets, even for the rapid fire stages of the NM course in the M14 or M16.

My opinion? Crimp 'em if you want. If you feel it is better for your shooting then your are wise to do it. After all, we all shoot better when we are confident of our equipment and ammo.

Me? As I noted in my first post in this thread, I crimp all my tube magazine rounds, cast bullet loads as well as black powder rounds, but I don't crimp at all for my match rifles, semi-auto rifles or bolt action hunting rifles. If there is a crimping groove on the bullet for those, then I'll consider it, but I don't see it as necessary.
__________________
Scharfschuetzer
US Army Distinguished Rifleman
Washington State Distinguished Rifleman
NRA Police Distinguished Expert

Last edited by Scharfschuetzer; February 24, 2012 at 05:17 PM.
Scharfschuetzer is offline  
Old February 24, 2012, 05:09 PM   #38
Slamfire
Senior Member
 
Join Date: May 27, 2007
Posts: 4,010
Quote:
So the guys at Perry shooting rapid fire in the service rifle match using 7.62x51 M1As (one of the fastest cyclic rates around), do not crimp their SMKs ?
Not that many M1a's on the firing line anymore. They rapidly disappeared after the Army started winning in the mid 90's. The last the Marine Corp Team shot M14's XTC was in 1996, half the team had M14's, the other M16's.

Long range, heck if I know.

I don't know any Master Class or higher service rifle shooter who crimps their bullets. Might be some marksman, but since everyone copies what the big dogs do, they would get out of the habit.

In terms of cycle rates, a AR or M14 is nothing compared with things like MG42's.

This is one of my better prone rapid fire groups, at 100 yards, with a M1a. I have never crimped.

__________________
If I'm not shooting, I'm reloading.
Slamfire is offline  
Old February 24, 2012, 05:13 PM   #39
Slamfire
Senior Member
 
Join Date: May 27, 2007
Posts: 4,010
Quote:
Exactly... its not as if a bullet leaves the bore in perfect condition.. the core is squeezed and deformed by the rifling more than a properly adjusted crimp die deforms it.... But like the die, its doing it from all sides, so no harm is done to the bullets flight....
This hypothesis is not sometime that I am going to spend time and effort testing.

But you can.

When bullet crimpers start winning National Championships I will start crimping bullets.

All you have to do is excel in competition. Results count. Go win a few for the crimper.
__________________
If I'm not shooting, I'm reloading.
Slamfire is offline  
Old February 24, 2012, 05:23 PM   #40
Mike38
Senior Member
 
Join Date: December 28, 2009
Location: North Central Illinois
Posts: 1,147
I crimp all rifle rounds that I reload. Even those intended for a single shot. I have tested many of my reloads, and have found I get right around 10% better accuracy using the Lee Factory Crimp Die. So they say, you will get more consistent ignition with the LFC die. It’s an extra step, but it works for me.
Mike38 is offline  
Old February 24, 2012, 05:46 PM   #41
steve4102
Senior Member
 
Join Date: December 23, 2005
Location: Minnesota
Posts: 2,130
Quote:
Decades ago, military arsenals used to crimp .30-06 match ammo bullets in cases just like regular service rounds are made. 'Twas either Hatcher or Whelen that said they really shouldn't do that 'cause it hurts accuracy. So one arsenal ran a lot of match ammo with half the cases crimped with different amounts of case mouth curl and the other half had no crimp at all. Since then, all arsenal rifle match ammo's never been crimped. And the scores were better too.
These tests were not done with the Lee Factory Crimp Die were they? How many different degrees or amount of crimp were tested. Did they do as handloaders do and test these loads with varying amounts of crimp using the Lee Factory Crimp Die? Or did they just slap on a heavy crimp like Speer did and proceed to tout the evils of crimping?

Last edited by steve4102; February 24, 2012 at 05:51 PM.
steve4102 is offline  
Old February 24, 2012, 06:00 PM   #42
steve4102
Senior Member
 
Join Date: December 23, 2005
Location: Minnesota
Posts: 2,130
Quote:
Nobody shooting centerfire rifles winning matches and setting records ever crimps a bullet.
No they do not. They also do not shoot off the shelf hunting or sporting rifles either. Should we not use these rifles cuz the Benchrest guys do not use them? There are a lot of things the benchrest doers do that we as hunters and sport shooters cannot do. Things like load long with the bullet pig jammed into the lands, indexing every round, chambers so tight that neck sizing or any sizing is not needed, loading single shot even in Semi-autos, you know thing like this that take the place of the Lee Factory Crimp die.
steve4102 is offline  
Old February 24, 2012, 07:18 PM   #43
HJ857
Senior Member
 
Join Date: January 9, 2007
Location: haslett, mi
Posts: 334
Quote:
When bullet crimpers start winning National Championships I will start crimping bullets.

All you have to do is excel in competition. Results count. Go win a few for the crimper.
If I were excelling in competitions and looking for every and any possible advantage, I really doubt that I'd be publicly revealing my secrets.

It would be really funny to learn that the top shooters have been crimping all along but saying that they would never even consider it.
HJ857 is offline  
Old February 24, 2012, 08:09 PM   #44
Bart B.
Senior Member
 
Join Date: February 15, 2009
Posts: 4,370
Mike38 mentions:
Quote:
So they say, you will get more consistent ignition with the LFC die.
Exactly how does one measure that "ignition" that the primer makes and not have any variables in the primers composition alter the results?
Bart B. is offline  
Old February 24, 2012, 08:24 PM   #45
Scharfschuetzer
Senior Member
 
Join Date: January 28, 2012
Location: Puget Sound
Posts: 293
HJ,

Good humor , but high power shooters are a pretty gregarious lot and share techniques and recepies like brothers. Not only that, but the team matches at the regional and national levels are usually considered more important than the individual matches as far as prestige goes between state teams and military teams. Team members share their info and data with each other in order to win. Secrets don't count at that level.

If there was a secret that produced an extra X, it wouldn't remain a secret for long ... not in the HP rifle community anyway.

Steve,

The fact that NM and long range rifles are not off the shelf rifles only strengthens the argument against crimping non-cannalured bullets. These rifles will shoot 10 shot groups well under the magic MOA at all ranges over the course. If there was an advantage to using the LFC die, these rifles would show it and pretty soon everyone would be using it to stay competetive. That hasn't happened and from my poor memory, the LFC die has been around many years now.

Like most topics, the truth usually lies between the extremes. As I noted earlier, many bullets are designed to be crimped, but I'm satisified with just neck tension on bullets not designed to be crimped and usully on cannalured bullets too in my bolt and semi-auto rifles.

The bottom line? Crimp 'em if you want. There's no law against it.
__________________
Scharfschuetzer
US Army Distinguished Rifleman
Washington State Distinguished Rifleman
NRA Police Distinguished Expert

Last edited by Scharfschuetzer; February 24, 2012 at 09:06 PM.
Scharfschuetzer is offline  
Old February 24, 2012, 08:39 PM   #46
dacaur
Senior Member
 
Join Date: March 16, 2010
Posts: 733
Quote:
Nobody shooting centerfire rifles winning matches and setting records ever crimps a bullet. Tests with rail guns fired in free recoil with the best of everything used to load shoot the very best match bullets into the tiniest groups possible......ever crimps a case mouth.
Again, they key here is match bullets. Match bullets are not the same as the bullets we FCD user's use. If I wanted to pay $1-$2 a bullet, I would just buy factory loaded ammo that works well in my gun. We are talking about cheap plinking or midrange hunting bullets, out of off the shelf guns, not high end "best of everything"......

Facts are facts..... And this is a fact: people who use the lee FCD, love it. People who have tried it, claim it either helps a little or a lot. Few people claim it doesnt help at all, (and I have yet to see a report of it actualy hurting accuracy.)
Another interesting fact: People who have never tried the FCD, love to tell everyone else how terrible it is.... based solely on the fact that, as far as they know, top shooters shooting match bullets out of match rifles, dont use it
see anything wrong with that picture?

Quote:
Your're doing something pretty attrocious with your hand/re-loading tools and/or processes that's masked by crimping in your bullets.
Again, what are are suggesting is pretty insulting, but even if thats the case, so what? A little group is a little group. My targets cant tell that I "ruined" my bullets with a FCD. I can get .5" 100 yard groups out of my $250 savage edge hunting rifle using polymer tip hunting bullets. just over an inch at 200.... I guess even though I am apparently a terrible reloader, this $15 hunk of metal fixes my ten thumbed attempts at reloading, and turns them into better than the factories can turn out.... Lee must be magic!
dacaur is offline  
Old February 24, 2012, 09:22 PM   #47
steve4102
Senior Member
 
Join Date: December 23, 2005
Location: Minnesota
Posts: 2,130
Unlike many others on this forum I have actually tested the Lee Factory Crimp die in several rifles, mostly semi-autos. I have tested it from light to heavy and with dozens of different bullets both with and without cannelure.

Here is just one of hundreds of test targets testing the LFCD. Same load except for the crimp. Target on the left no crimp target on the right LFC.
I'm not sure as I do not have my notes in front of me, but I think this target was with 53gr Sierra Matchking.


I know, I know, not a large enough sample, only one target, means little or nothing etc. etc. Like I said this is just one of hundreds with similar results. Can't post em all now can I.

For those of you that have nothing good to say about the LFCD how about posting some of your targets where the use of the die degraded the hell out of accuracy?
steve4102 is offline  
Old February 24, 2012, 09:40 PM   #48
Slamfire
Senior Member
 
Join Date: May 27, 2007
Posts: 4,010
Quote:
Good humor , but high power shooters are a pretty gregarious lot and share techniques and recepies like brothers. Not only that, but the team matches at the regional and national levels are usually considered more important than the individual matches as far as prestige goes between state teams and military teams. Team members share their info and data with each other in order to win. Secrets don't count at that level.

If there was a secret that produced an extra X, it wouldn't remain a secret for long ... not in the HP rifle community anyway.
Very true.

Ask any competitive shooter his load and you will get the full data. Don't ask them how they did unless you want to spend an hour listening to a shot by shot boring as hell repetition of a 20 shot string.

Here is the secret: They share load data because that really won't hurt them or help you. They can give you their rifle, their load, their coat, their scope, everything, and they will still out shoot you.


Quote:
For those of you that have nothing good to say about the LFCD how about posting some of your targets where the use of the die degraded the hell out of accuracy?
Why would I want to take the most perfect bullets ever made in the history of the human race and turn them into crap?

Early on I stopped using the Lee Factory Crimp die when I found the thing "coke-bottled" my 168 SMK's. I shot those bullets standing, and I cannot prove they made my score worse, or better!
__________________
If I'm not shooting, I'm reloading.
Slamfire is offline  
Old February 24, 2012, 10:08 PM   #49
Mike38
Senior Member
 
Join Date: December 28, 2009
Location: North Central Illinois
Posts: 1,147
Quote:
Mike38: So they say, you will get more consistent ignition with the LFC die.
Quote:
Bart B.: Exactly how does one measure that "ignition" that the primer makes and not have any variables in the primers composition alter the results?
Should say burn, not ignition. Sorry for the mistake. But something tells me you knew what I meant.
Mike38 is offline  
Old February 24, 2012, 10:31 PM   #50
Jim243
Senior Member
 
Join Date: January 5, 2009
Posts: 4,331
Quote:
Deforming the core of a bullet and deforming the jacket will change the center of gravity. As that bullet rotates, with a center of gravity now outside the center of rotation, this will add inaccuracy.
You can crimp or not crimp based on what works best for YOU.

It would appear that the writter of this quote does not take into account what the heat of the powder does to the bullet in the chamber and barrel, yep, 35,000 to 60,000 psi has no effect on the bullet. If you could stop and check the bullet at the end of the barrel just as the bullet comes out you will see no crimp marks, the bullet has been compressed into the shape and diamiter of your bore with rifle groves (melted into shape).

So crimp away and it will give you a complete burn and faster fps.

Jim
__________________
Si vis pacem, para bellum
Jim243 is offline  
Reply

Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off

Forum Jump


All times are GMT -5. The time now is 05:14 AM.


Powered by vBulletin® Version 3.8.7
Copyright ©2000 - 2014, vBulletin Solutions, Inc.
This site and contents, including all posts, Copyright © 1998-2014 S.W.A.T. Magazine
Copyright Complaints: Please direct DMCA Takedown Notices to the registered agent: thefiringline.com
Contact Us
Page generated in 0.12955 seconds with 7 queries