Lee factory crimp die help

[X ring 7mag]

hey guys, here's a quick question. i recently ran my first batch of 7mag ammo through a lee crimp die. of the 10 rounds that i crimped, 3 were buckled in the shoulder area. a friend of mine (also new to this die) had the same experience with the die in a different cxaliber. any words of wisdom to prevent this scenario?

 

[.260 Handgun]

The only way that I could see the factory crimp die buckling the case is if the case was to short. Check to make sure that you can see the edge of the case above the actual crimping part of the die. Since the crimping insert is free floating in the die sleeve I don't see any other way that enough pressure could be put on the case to cause the shoulder to buckle. Assuming of couse that the die's internal demensions are correct and the case shoulder is not pushed forward (2.040" according to my books).

Word to the wise, if you're crimping a full length sized rifle case you may be wasting your time. I could never see an accuracy difference between the crimped and not crimped case in my rifles. And a full length sized case should hold the bullet in place even in a heavy recoiling rifle. I think I would only use the factory crimp die if I was neck sizing only, as the case usually doesn't hold the bullet as tight. But if it works better in your gun, keep doing it.

 

[Ol` Joe]

Are you seating and crimping at the same time? I suspect you are still moveing the bullet as the crimp is being applied. The bullet movement is compressing the case and crushing the shoulder. Do each as a seperate step in your loading.

I have no experiance with these dies as I crimp only handgun ammo, but I too see no need to crimp, unless you`re loading for a semi-auto or a very heavy recoiling rifle with heavy for caliber bullets.

BTW,
Neck or FL sized, the neck tension on the bullet should be very similar and plenty to hold a bullet firmly in the case. It all depends on the amount of resizing the die does to the case neck and how large in diameter the expander ball is.

 

[Blaine]

Ol Joe, the factory crimp die is a separate die. You can't seat a bullet with it, is for a factory taper crimp only.

xring, I'm not trying to be overly simplistic, or offend you, but there are 2 questions that come to mind. I have been using the Lee factory crimp die on all of my loads and I have never buckled a case.

1) Are you absolutely sure that the stamp on the side of the die is what you are trying to crimp? I know this sounds stupid, but it's possible that the wrong die was put in the case before it was shipped.
2) Are you following factory instructions exactly? If the die is screwed down too far, it could collapse the neck.

As to accuracy, I disagree with 206 handgun. I have done side by side tests with some of my best hand loads and there is definitely an improvement with the taper crimp ammo. Both in accuracy and in consistency (SD's and velocity spreads). I taper crimp everything I load. Some disagree, but I can't argue with the empirical data I've collected. If you have double checked both points 1) & 2) above, I would send the die back to Lee and explain what is happening. I'm sure they will make it right. I've had nothing but excellent service from them.

Blaine

 

[X ring 7mag]

hey all, here's the low down. yes, the die does match...no offense taken. as to the factory directions, as i interpret the directions, "yes" i am following them. i don't have them in front of me, but as well as i can remember, as the die tightens towards maximum crimp...the four slits in the top of the die will close. when i crimped this batch, 2 of the four slits did in fact close...do i assume that 2 closed is the equivalent of all closed? that thought did cross my mind. however, the fact still remains that 7 of ten were ok. as far as accuracy? yes, they did in fact tighten a proven load even further. i don't know the measurements, but five shots at 100 ended up as one big hole (64 grns imr 4831, 150 grn BT). velocity was also much more consistent. thanks to all for your input, if anyone thinks of anything else, please post it.

 

[Cazador]

I think your problem is that you didn't trim your brass to the same length before crimping and the brass longer than spec. is being grabbed too soon and pushed down when you crimp. I too crimp all my loads and seem to see some improvement on some loads but none of my loads are worse for the crimp. I'm not a good enough shot to tell if I'm gaining or losing a !/4 in. here or there.

 

[Blaine]

two closing is not the same as all 4 closing. The slits should all be equal in closure, whether closed all the way or only partially. If not, something is catching/binding. As has been said, make sure all your cases are trimmed to the same length. If this doesn't solve the problem, you need to send it back to Lee.

Blaine

 

[X ring 7mag]

hey guys. i've just seen the latest postings, and must admit that the brass in question was not trimmed or mic'd. i did size it and i did chamfer it, but as it was new, i assumed that it would be ok on length. riddle me this...isn't the selling point of the lee die the fact that it doesn't rely on length for its crimp? or am i misquoting...is it that it doesn't depend on oal? never the less, i will try trimming on the next batch. thanks to all. again, if anyone would like to add to this, please do.

 

[steve4102]

hey guys. i've just seen the latest postings, and must admit that the brass in question was not trimmed or mic'd. i did size it and i did chamfer it, but as it was new, i assumed that it would be ok on length. riddle me this...isn't the selling point of the lee die the fact that it doesn't rely on length for its crimp? or am i misquoting...is it that it doesn't depend on oal? never the less, i will try trimming on the next batch. thanks to all. again, if anyone would like to add to this, please do.

You are correct! The Lee Factory Crimp Die does NOT need the brass to be all the same length to work. In fact the only place the die should contact the brass is at the end of the neck. If the brass is long the crimp will be farther into the neck and if it is short it may not crimp the brass at all, but, it will not affect the case. Sounds to me like you have a problem with the die not opening and closing evenly. All four segments of the die should and must be closed or open equally. If the die does not return to it's original (open) position after you crimp a round then the next round may get caught on the semi closed jaws and buckle the case. The die in the open position should allow the neck of your brass to fit easily between the jaws. Raising the ram will close the jaws and crimp the round. I think you need to remove the jaws from the die and do a little investigating, look for burrs or other debris that could restrict your dies movement. Clean it up good and put a little dab of oil in there too.

 

[X ring 7mag]

one last note...i loaded another batch of ten this evening with no buckled casings. i'm positive that this was due to the depth at which the die was seated, but to be safe, i also trimmed each case within .oo2. at any rate, the die worked as prescribed, all 4 slits were even, and all cartridges came through with an even crimp. thanks again to everyone who responded.