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BorderBrewer
04-19-2005, 11:37 AM
Hi All,
I wanted to ask what folks were using to crimp cast bullets. I have been using the LEE factory crimp die for 38 and 44 special. Is this a satisfactory crimp die for cast bullets?
Thanks,
BorderBrewer

454PB
04-19-2005, 11:54 AM
I use the standard crimp dies supplied with light recoiling rounds like .38 special and .44 special. I do use the Lee factory crimp dies for .44 magnum, .454 Casull, and .45 acp. I own several .45 acp pistols, and have found that I need to use the Lee crimper to insure that my handloads will feed in all guns.

I don't see that using the Lee crimper for everything would hurt anything, it's just an additional expense and more equipment to store (like I don't have enough already!).

Willbird
04-19-2005, 12:36 PM
For mild loads you may just want to iron out the flare, I assume you can do that with the factory crimp die, the less flare and crimp you can get away with lengthens the life of the brass


I prefer a taper crimp for 45 acp as I feel it makes the ctg. feed better.

Bill

Wayne Smith
04-19-2005, 01:38 PM
I've only used the Lee Factory Crimp die for my 44-40, for the .38 Special and .357 Mag. I'm using the crimp on the bullet seating die without problems so far. I always try to use the bullet seating die to crimp first, and if for some reason it doesn't work then I'll buy the Lee Factory Crimp die.

slughammer
04-19-2005, 07:17 PM
Hi All,
... LEE factory crimp die for 38 and 44 special. Is this a satisfactory crimp die for cast bullets?


Just be carefull with those Factory Crimp Dies, make sure that the carbide ring is not resizing the neck area. If the carbide is resizing the neck area, it is also resizing your boolit. If your boolit is resized, you'll be loosing case neck tension.

StarMetal
04-19-2005, 07:41 PM
As I understand it and looked at the crimping ring it only catches a ver minute part of the very end of the neck. You're taking like maybe 2 percent of the total neck area which isn't anything at all to be concerned with. I think they are a heck of alot better then turning the factory seating dies down to roll a crimp in.
I know on the rifle Lee factory crimp you can't crimp more area of the neck, impossible. I just ordered a special factory crimp they recently come out with for the 30 Luger, also the 7.62x25 Tokarev and 30 Mauser.

Joe

Bass Ackward
04-19-2005, 09:30 PM
Hi All,
I wanted to ask what folks were using to crimp cast bullets. I have been using the LEE factory crimp die for 38 and 44 special. Is this a satisfactory crimp die for cast bullets?
Thanks,
BorderBrewer

Brew,

Depends on how you use the die. To answer this fully, you must look to the type of crimp groove that you are dealing with. A Lee factory crimp die would be excellent for crimping in a shallow grease groove because it squeezes to a flat spot thus folding brass down over the rear taper of the groove. (rifle bullet) But this much crimp force would actually deform a crimp groove that was cut for a roll type crimp. (most handgun designs)

To deform the crimp groove means that you deformed a cast bullet that you painstakingly created and culled to the highest standard. This would make some people cringe. And some not at all.

The best crimp is always the one that provides just enough force that it maintains maximum brass / lead contact. Anything beyond that deforms and weakens. What you use to obtain this standard should be of minor concern. Just go with what works for you.

The positive to a seperate crimp die is that you seperate the seating and crimping functions. Some folks swear by this for elimination of bullet deformation. Others dismiss it as an unnecessary step. I can't say that I have seen it work miracles in a wheeler. At least as well as I shoot one. But I can make a noticeable difference in a rifle.

One other advantage to a factory crimp die is that you can crimp a bottle neck cartridge. So it can do away with a need for fillers which are remarkably inconsistent unless you have a method for perfect volume selection. Why weigh a powder charge if you are going to .... guess on a quantity of filler. A crimp improves ignition without altering the burn rate characteristics of the powder you are using because of a change in case volume. And this is my real gripe with fillers.

45 2.1
04-19-2005, 10:07 PM
One other advantage to a factory crimp die is that you can crimp a bottle neck cartridge. So it can do away with a need for fillers which are remarkably inconsistent unless you have a method for perfect volume selection. Why weigh a powder charge if you are going to .... guess on a quantity of filler. A crimp improves ignition without altering the burn rate characteristics of the powder you are using because of a change in case volume. And this is my real gripe with fillers.

A crimp can have several functions. The above statement doesn't really reflect what those are though.

drinks
04-19-2005, 10:10 PM
I much prefer to seat and crimp seperately, of course, 95% of the bullets I load are cast and seating and crimping at the same time can cause some shaving.
The Lee factory crimp die is nice, if you do not adjust it down all the way, it does not crimp much, you just have to decide how much is enough.
If the case has a lot of space above the powder, I use the Lyman 1/4" quilt batting wad, a 1/2" square will keep most any powder charge back against the primer.
Don

StarMetal
04-19-2005, 10:47 PM
Bass

Well Bass I'll have to disagree with you on fillers. Some of the most consistant AND accurate loads I have fired in countless guns where with fillers. We're talking like 1/10th of a grain of filler. Shucks, that's not enough to change things a whole lot. But that's ok, if you don't like them fine. I"m happy shooting some mighty small groups with my rifles using cast and fillers.

Most my revolver cast bullets have very pronounced crimping grooves. For example my 255 gr SWC RCBS for the 45 LC has a deep crimp groove that is tapered the correct way for the brass case mouth to fold into it. If you set your seater up correctly (I'll call it seating and crimping timing) it will not shave brass at all.

Different strokes for different folks.

Joe

BorderBrewer
04-19-2005, 11:00 PM
Thank you all for the great information. I have purchased LEE factory crimp dies for all my calibers except .32 Special (which I can't find listed in Midway's or Lee's catalog). Bass's advice to not overcrimp is sound. When I first started using the crimp die for .38 special, I overdid it while trying to adjust the die. I later ended up pulling the bullet on the cartridge I was adjusting with to find that I had squeezed it to .356 diameter. oops!

StarMetal
04-20-2005, 08:03 AM
Border Brewer

On Lee's website there is a section for special order dies and they will make you a 32 Win Spcl factory crimp die for $25 + $4 shipping.

Joe

beagle
04-20-2005, 08:18 AM
Yours is probably the best way and one that I prefer. Too many people are in a hurry and want to do it all in one pass.

Then, there's always the trick of "taper" crimping with a FL resizing die.

When you get down to it, all the crimp that is required is a tiny bit to iron out the slight bell you put in the brass for seating cast bullets. If you're expander diameter is right, the bullet tension will be there.

But saying that, I do crimp my straight walled pistol cases. The only problems I've ever had was on a batch of .41 Mags that I got at a gun show one time when I was desperate./beagle

45 2.1
04-20-2005, 08:28 AM
I repeat, a crimp can have several functions. Sometimes, to achieve benchrest accuracy, you will have almost no neck tension. The crimp is then necessary to get the powder to correct ignition pressure. Not everything you read is correct.

Bass Ackward
04-20-2005, 12:04 PM
I repeat, a crimp can have several functions.

Sometimes, to achieve benchrest accuracy, you will have almost no neck tension. The crimp is then necessary to get the powder to correct ignition pressure. Not everything you read is correct.

Bob,

I am embarrassed and willing to show my ignorance for the purposes of education.

I can only think of two functions for a crimp.

1. To hold the bullet in place.
2. To seal the contents from the elements.

Are there more that I am missing? All of the reasons I can possibly think of are traced to these two.

felix
04-20-2005, 01:09 PM
Actually, BA,

I can only think of ONE function for a crimp.

1. To hold the bullet in place.

You can apply a glue to seal the contents of a cartridge, as might be done for cartridges used in high humidity locations with wild ambient temperature swings.
A motor wire varnish made by PD George company in St. Louis would be the cat's meow for this purpose. Just paint the entire cartridge for hunting rounds. If someone is really interested in this, I can contact the company for some "samples". Please don't request any unless you are in DIRE need for such a paint. This is a hazmat type of paint.

felix

StarMetal
04-20-2005, 01:19 PM
Well holding the bullet in place is about all I can think of. Like Felix said the seal in the function of the crimp. I think a better seal is the asphalt that was orginally used if one can find it. I surely can't believe that the factory would crimp to help ignition. Anything that you can mention like so the bullet don't get pushed in the case deeper in tube fed magazine, to heavy recoiling big game rifles, to the nose getting bumped in semi-auto pistols, so the bullet doesn't fall out when the cartridge is in a cartridge belt, etc...all still fall under to keep the bullet in place.

Joe

felix
04-20-2005, 03:12 PM
No, Joe, the best seal today is a quality varnish. That would keep the case resizable without gunk. The metal cases used today are painted with this kind of varnish. A thin and tough glue, that won't come off with many resizings. ... felix

44man
04-20-2005, 05:32 PM
I use Redding profile crimp dies for most of my revolver cartridges. On some I use the crimp from the seating die and with some of the new Hornady dies that come with a taper crimp die, I use them. All of them work.
There is only one purpose for crimping with revolvers, lever guns or any other magazine gun that has a lot of recoil and that is to keep the next boolit from moving when the first is shot. Any boolit that is driven deeper into the case will raise pressures and any that pull out will tie up a gun. For single shots or guns with very low recoil, no crimp or a very light one is all that is needed.
I made extensive tests over a period of 5 years with various crimps and no crimps with big bore revolvers and there was no difference in accuracy although some had to be loaded and shot single shot.
The most important thing was boolit pull or seating pressure which ever way you look at it. The crimp, in no way, effected the powder burn, velocity or accuracy. But boolit pull did change it drastically and also had a profound change in the point of impact. I had a system set up to measure seating pressure to separate rounds into groups and the difference would be as much as 10" in the point of impact at 50 yd's. between light boolit pull and heavy pull. By taking the rounds with a light seating pressure and applying a very heavy crimp, no difference of any consequence could be determined.
The final test was to take 50 rounds of the most accurate load and the most even seating pressure and apply different crimps to all of them. No difference was found in the groups from all 50 shots.
If anyone thinks that the crimp alone will change powder burn or accuracy, I can say that it is so small as to be not worth considering.
The problem is much less with bottle neck cases as the bullet can be seated to contact the rifling and the shoulder retards the foreward flow until the powder gets a good start.
Shooting black powder in straight wall cases is not as touchy either. In fact most BPCR shooters do not size brass and hand seat boolits with no crimp. The flare is ironed off so rounds chamber easy.
If you are shooting light recoiling revolvers, just put enough crimp to hold the boolit, use just enough flare to make starting the boolit easy and case life will be long. If you load hotter, determine how much more crimp you need and don't get carried away and ruin brass or buckle cases. It is surprising how little crimp is actually needed even in the .475 Linebaugh with 400 gr. boolits and up. I have cycled one round while shooting 12 other full house loads without the boolit moving. My crimps are just moderate. Boolit pull is what does the trick.

slughammer
04-20-2005, 05:37 PM
Guys please reread the original post, borderbrewer is asking about 38 spl and 44 spl.

The Lee FCD for straight walled pistol ammo DOES NOT resemble the collet FCD for bottle neck rifle ammo. Two totally different animals.

99% of the time, the only thing I rely on a crimp for is to remove the belling operation.

45 2.1
04-20-2005, 06:55 PM
Bob,

I am embarrassed and willing to show my ignorance for the purposes of education.

I can only think of two functions for a crimp.

1. To hold the bullet in place.
2. To seal the contents from the elements.

Are there more that I am missing? All of the reasons I can possibly think of are traced to these two.

Bass-
Normally, people think the crimp is to keep the bullet in place, either from pulling or pushing into the case. Crimp is also used to control the burning characteristics of the powder in use or to retard the release of the bullet. It really depends on just what the objective is. This can be a very comprehensive subject just as use of fillers is. Do you remember the fight between LEE and I think Speer when LEE brought out there factory crimp die. It was claimed that the factory crimped helped the powder to burn correctly, which was a very true but very new statement to most reloaders. The degree of crimp changes the function of how a powder burns. Powders, depending on how fast they burn, usually need some restraint to reach a certain pressure to burn correctly. The slower they burn, the more restaint they need. Either from heavier bullets, filler use or crimp. It can also effect just how good of accuracy you can obtain.

Bass Ackward
04-20-2005, 06:57 PM
Actually, BA,

I can only think of ONE function for a crimp.

1. To hold the bullet in place.


felix

Felix,

Well OK. I was thinking of the military as they crimp necks and primer pockets to seal out moisture. But as far as cast goes, I would say one.

Hey Felix. Joe has some bubblegum that would make a good sealant. He was trying to con me into using it for lube but I fooled him boy. Couldn't get it to blow bubbles worth a darn. And it had a slight petroleum odor, but it lasts a long time. :)

imashooter2
04-20-2005, 07:27 PM
Felix,

Well OK. I was thinking of the military as they crimp necks and primer pockets to seal out moisture. But as far as cast goes, I would say one.

-snip-

The military crimps the case mouth and primer pockets to ensure a pushed back bullet or blown out primer doesn't tie up the gun. They waterproof the case and primers with lacquer and/or tar type sealants.

StarMetal
04-20-2005, 09:16 PM
Yeah, I said Bass some bullet lube I made and he thought it was bubblegum. I said "God no, don't chew that stuff".

Joe

felix
04-20-2005, 09:33 PM
Yes indeed, I also use crimp power to hold a boolit back a little more for better ignition when using the slower powders. A better and more consistant way is to use a smaller expander plug and use a light crimp only. But that assumes you don't resize cases until needed that day for a load in mind. Unfortunately, these days I just go ahead and size cases when there is nothing else to do with no load in mind. In this situation, I tend to expand the cases more to avoid squishing the boolits too much. Always best to load from scratch with a boolit and load in mind up front. ... felix