Roller crimp or factory crimp

[Sven Dufva]

I wonder what sort of crimp you prefer to cast bullets? Do you crimp hard?
Self i prefer roller crimp on 357mag and 44mag and if it is hot loaded an hevy crimp. I use slow burning powder in hot loads that prefer hevy crimps to burn out.

[David R]

For me, roll crimp on revolvers and taper crimp in a seperate step for semi auto peestols.

[44man]

The roll crimp is OK but I find the profile crimp more accurate on my .44 and .45. My Hornady .475 set came with a seperate crimp die and it is labeled in the paperwork as a taper crimp but it looks more like a profile die to me and it works fine.

[BABore]

The roll crimp is OK but I find the profile crimp more accurate on my .44 and .45. My Hornady .475 set came with a seperate crimp die and it is labeled in the paperwork as a taper crimp but it looks more like a profile die to me and it works fine.

44Man

Have you pulled any bullets and measured the diameter. I found that my 475 Hornady crimp die was resizing my cast bullets down to 0.473 on the first two bands. This die also resizes the case bulge for easy chambering which is why it screws up the cast bullet. I don't use it anymore. I do a seperate crimp with the seating/roll crimp die.

[StarMetal]

BABore

The right way to pull those bullet to measure them would be to split the neck, the portion that is actually holding the bullet, gently remove the bullet and measure it. I say this because under actual firing the case doesn't react the same as when you're just "pulling" the bullet. The case is being expanded some as the bullet begins moving in real firing. Try it and see if your measurement comes out different.

Joe

[Blacktail 8541]

44man, Which profile crimp dies do you use? Do you find they provide an edge in accuracy or more consistant velocities.

[Bucks Owin]

I wonder what sort of crimp you prefer to cast bullets? Do you crimp hard?
Self i prefer roller crimp on 357mag and 44mag and if it is hot loaded an hevy crimp. I use slow burning powder in hot loads that prefer hevy crimps to burn out.

Be careful with trying to make roll crimps TOO tight. You can actually loosen the boolit when the case starts to buckle outwards slightly....

FWIW,

Dennis

[BABore]

BABore

The right way to pull those bullet to measure them would be to split the neck, the portion that is actually holding the bullet, gently remove the bullet and measure it. I say this because under actual firing the case doesn't react the same as when you're just "pulling" the bullet. The case is being expanded some as the bullet begins moving in real firing. Try it and see if your measurement comes out different.

Joe

Yep, I did it that way too. It's even visually evident as you can see the case bulge from the newly seated bullet. After it goes through the crimp die, the bulge is gone, resized. I even spoke with the design guys at Hornady. Base on case, die, and bullet dimensions there is a definite sizing operation going on. They were going to look into problem and do a design review. The Lee FC pistol die also do a similar resizing operation. Both Kelly, at Cast Performance Bullets, and Dan at Mnt Molds are familiar with this problem.

I got into some lengthy conversations with Kelly and Hornady about this when working on a related problem. I had a bullet nose fracture on one of CPB's 475 cal,400 gr WFN bullets when I shot a buffalo last year. Most of the fault lies with the die. Because it resizes the case and contains it so well, it will allow you to overcrimp without knowing it. On a normal roll crimp die, if you over do it, you'll buckle the case. Not so with the Hornady. I basically caused a fracture in a heat treated bullet with 6% antimony. A rather large buff rib finished the job. At least it was the off side rib. On the positive side, this bullet problem was what got me into casting my own.

[44man]

I see some of you are overcrimping with the Hornady die. I have pulled my .475 boolits with a hammer puller and found no reduction in boolit diameter.
For the .44 and .45 I use a redding profile crimp die and get no boolit reduction with them either. I get an increase in accuracy from both. As long as groups are tighter, I don't care what the SD is.
My boolits are hard but not brittle. If you are crimping hard enough to fracture boolits, the alloy is wrong and the crimp is WAY too hard. The crimp should only hold the boolit in place under recoil and no more.
I will never understand why some of you need such a hard crimp. It doesn't do anything but ruin boolits and brass.
BaBore, I have shot thousands of rounds from my .475 without a case loss, damaged boolit, broken boolit or lost game. The bulge of a seated boolit should NOT be ironed out with the crimp die. This case tension is what you want! Hornady makes the most accurate loads of any dies and to complain to them will defeat the dimensions that work. I still see the grease grooves and bulge after crimping with the Hornady die so I can only guess you are overcrimping in the extreme. Either that or they changed something since I bought my dies.

[454PB]

When I first started shooting .454 Casulls, I did some crimp testing. I'd fire four rounds, then leave the fifth one in place, reload and fire four more. There is no better inertia boolit puller than a heavy recoiling handgun. I learned how much crimp was required to keep the boolits from moving forward in recoil and tying up the gun. There's no reason to crimp more than what is required to prevent boolit movement in the loaded case.

I have several of the Lee FC dies, but they tend to resize the boolits within the case.

It's now my practice to seat and crimp in two operations, this insures no lead shaving and consistent crimps by "feel".

[Bucks Owin]

It's now my practice to seat and crimp in two operations, this insures no lead shaving and consistent crimps by "feel".


Absolutely! I think everyone should do that if they are after maximum accuracy...

And I agree with the notion that folks are generally way too "energetic" with their crimping. The less the better IMO, however I think a lot of handloaders try to follow "advice" in the various loading manuals who advocate "tight" crimps. I think it's Hornady who even says to adjust the crimp until it "distorts the cannelure". Good Lord!

It's impossible to "crimp your way" to a tighter bullet pull IMHO. Only a change of dimensions can do that, either with the expander or bullet sizer.....(or an "adhesive" which HAS been done BTW...)

JMO,

Dennis

[StarMetal]

BABore,

Okay, I believe you. You seem to have a combination of things wrong and that over crimping the main one. Now...I only have a couple Lee FC dies. One for my 7.62x39, 762.54R, and my 30 Luger. I can gaurantee you that mine or those don't size down any part of the neck except the very very edge that it puts four long crimps into directly 90 degrees into the case mouth. Now I would suppose of the neck/bullet are drastically fat it may swage them in, but mine don't.

Joe

[Bucks Owin]

Yeah, the Lee "Factory Crimp" dies are a different animal from conventional dies. I don't own any but hear good things about them and the way they "swage crimp" for lack of a better term...

Dennis

[StarMetal]

Dennis,

Well some of the fellows in previous posts mentioned specifically Lee FC dies. Isn't FC Factory Crimp???

Joe

[Bucks Owin]

Dennis,

Well some of the fellows in previous posts mentioned specifically Lee FC dies. Isn't FC Factory Crimp???

Joe

'scuse me Joe...

Dennis

[StarMetal]

No problem Dennis....I was just getting confused. Like I posted I can't see how a factory crimp dies sizes your bullet unless it's drastically fat and the shabangs is big..cast neck and all. Or maybe using a factory crimp die for the wrong caliber....I dunno.

Joe

[Dale53]

Keep in mind that the Lee Factory Crimp die for rifles is quite different than that for revolvers. Like any tool, you DO have to learn to use them for best results.

Me, I like both of them. Innovative technology...

Dale53

[drinks]

Bucks Owin;
There are 3 Lee factory crimp die types.
The one for bottleneck cases crimps sideways a very narrow ring, in 4 segments, on the very end of the case mouth.
I use these on all my rifle cases and my .45-70, too.
The die for revolvers puts a roll crimp on cases and the die for SLs, makes a taper crimp.
Both of the dies resize the case and bullet to assure that the loads will chamber with no problems, but if they are adjusted down too much, they may loosen the bullet by sizing down the cast bullet and then the brass springing back but the bullet not.

[454PB]

With the Lee FC die in a revolver, you better be using the "industry standard" boolit size or smaller, or it WILL size the boolit. In my .45 Colt/.454 Casull Lee FC, any boolit over .452 gets squeezed, and the thicker the brass, the more it gets squeezed.

[Dale53]

Drinks;
Oops! I forgot about the bottle neck FCD.

Dale

[Bass Ackward]

I wonder what sort of crimp you prefer to cast bullets? Do you crimp hard?
Self i prefer roller crimp on 357mag and 44mag and if it is hot loaded an hevy crimp. I use slow burning powder in hot loads that prefer hevy crimps to burn out.


Sven,

Crimp is just another .... option or tool that some people prefer to use and some don't. Most people, (well my reason anyway) don't change crimp because of the need to change their dies. And they feel crimp was so hard to set up in the first place, that they can live without change in this case. I am so lazy that I will even have different seating dies for different bullet designs. And I have designed bullets with the same crimp groove and nose length so I wouldn't have to change anything.

Crimp has much less effect the slower in powder burn rate you go and at some point merely becomes a tool to prevent a bullet from pulling forward. But if you use light for caliber bullets that don't have the bearing length or seating depth in a case where case tension makes much difference, then crimp takes on a whole new meaning. With powder selections, where the burn rate approaches 100% with those components, I can make a greater velocity difference with crimp than I can by changing primer in some cases.

I never shoot rifles at low enough velocities that crimp has made much of a difference if I can seat into the lands. On the other hand, I am more prone to slow a handgun down some these days for the arthritis in my hands. So I am learning all over again how to use one.

[hopper_64]

I wonder what sort of crimp you prefer to cast bullets? Do you crimp hard?
Self i prefer roller crimp on 357mag and 44mag and if it is hot loaded an hevy crimp. I use slow burning powder in hot loads that prefer hevy crimps to burn out.

Hi nice to see another Swede on the board:)
In my autos I tapercrimp just hard enough so the bullet don't get pushed back in the case when it hits the feedramp.

In .38, .357 and .45colt I rollcrimp, apart from hot loads with heavy bullets (+300gr) in .45colt where I use a profile crimp die.

http://castboolits.gunloads.com/showpost.php?p=64459&postcount=45

Jocke