lee factory crimp die

[beerbelly]

I wanted to try the lee factory crimp die, so I got one and here are the results. With out the crimp and using 45 grains of H414 and a Hornady 174 grain RN SP, I got an extreme spread of 87 fps, with a standard deviation of 32. All were six round strings.
 With the Lee factory crimp a round with an extreme spread of 25 and another of 19. With a standard spread of 11 and 6 .
 Average velocity was 2200, 2211, and 2224. I was loading 303 British.

So I did get better numbers, couldn’t tell any difference in accuracy, but with my old eyes nothing is going to help there.
                                        Beerbelly

[Larry Gibson]

Results are going to vary with the Lee Factory Crimp Die.  In some cases, like yours where a hard to ignite ball bowder is used the crimp helps with more uniform ignition.  In cases where neck tension is sufficient, throats are short, bullet weight is sufficient and powders easily igniteable then there isn't much improvement with the use of a crimp.  I've done several tests with several different cartridges and have found the above to be the general case.  I find the Lee Factory Crimp to be most useful in simply applying a factory type crimp.  This is especially the case with milsuep bullets like M80 and M193 which have a "waspy" waist.  Roll and tapered crimps do not put an adequate crimp.  I "reloaded" thousands of Turk 8mm reducing the powder charge 5% (the old brittle Turk cases then do not "stick" during bolt opening), neck sizing and then using a LFCD.  Also when loading M2 bullets there's not much seating depth to the, so the LFCD works very well.  Most milsurp bullets (150/154 '06 and 8mm and FMJBTs) don't have a lot of bullet bearing surface seated into the case. Thus neck tension is minimal for the initial stage if pressure curve.  A good crimp can and does assist in these cases.

One additional use is to crim into bullets that do not have a canelure.  I do this hardly at all but the one exception being with 400 gr Barnes SPs loaded in my 45-70 Siamese mauser.  These are loaded to the Maximum (a 4th level for 45-70 loads but still within modern psi's for the action) and to maximum OAL for the magazine.  The throat has been reamed for this load.  This load runs 2300 fps with the attendant recoil associated with a 8 1/2 lb rifle.  The bullets must be crimped and there is no canelure on the  Barnes bullets.  I used to roll a canelure on with the CH tool but couldn't get a good enough roll crimp to keep the last bullet in the mag from walking out of the case during recoil.  The LFCD solved that as I seat the bullets and then crimp the case mouth into the sides of the bullet.  No more bullet walking under recoil, even being left in the mag for 10 shots. 

Thus I do use several of them for several cartridges.  That's my take on the Lee Factory Crimp Die.

Larry Gibson

[Bart Solo]

I use the Lee carbide factory crimp die that came with my 4 die set to roll crimp 45 Colt.  Of course a crimp is mandatory when loading straight walled 45 Colt cartridges, but the crimp die is very easy and effective. 

[Siskiyou]

Did you crimp earlier rounds with the standard roll crimp in a bullet seating die?

After observing how the Lee factory Crimp dies works, and the quality of ammunition produced I am conveniced.  I am currently using one for the 30-30 and another one for the .270.

[cwlongshot]

 Personally, I have never had a need for anymore crimp than the taper/roll crimp built into the Redding/RCBS/Lyman dies I prefer to use.

I dont like and see no advantage to the excessive crimping and resulting damage this die does to the mouth of the brass. JMHO

CW

[wncchester]

Some rifles respond to crimping, it appears yours is one and it's good that you took the time to actually find out.  Most of my rifles also do slightly better with crimping but nothing is always true in reloading so making a blanket statement for others on what works or doesn't for me would be foolish!

No matter the style of crimp or who made the die, a good loader will adjust his die to obtain the degree of crimp he actually needs and wants, there's no need to over-crimp anything.   Since discovering Lee's collet type rifle crimpers many years ago I haven't used anything else!

[Savage]

I use the LFCD for all of my pistol/revolver loads as well as for the 5.56 for my ARs. I wouldn't be without mine. Need to pick up one for the 7.62x39 as well. Looks like I'm going to have to load for the AKs too.
Savage

[Autorim]

I have never crimped rifle loads for bolt actions or single shots. I do crimp the .357 in the Marlin lever action. I also shoot the Mini14 in .223 and do not crimp it either. I have loaded quite a lot of ammo for a Marlin 38-55 without crimping, but shot them single rounds only.

I use the Lee crimp die for all of my handgun cartridges that are not loaded in the Dillon. It works just fine and is easily adjustable to the desired amount of crimp. I set up the seater/crimp die to seat only and crimp in a separate operation with the Lee. I agree that excessive crimp can cause more harm than good.