Good Day to All:

I was messing around with my Lee Factory Crimp Die for my 9.3x74R.

I noticed a compresion ring around one of the bullets I pulled and realized I had way too much crimp on my cases.

I tried an experiment where I took a resized case and measured the inside neck (.369). Without a projectile, I ran the case up into the Lee Factory Crimp Die. I removed the case and re-measured the neck (.360).

The projectile is of course .366 and therefore I should have a factory crimp of .006.

Before conducting this experiment I had the crimp at well over .010 and it was crushing the bullet in a circular pattern around the bullet creating a canalure where there was none.

Interestingly, at 50 metres, with several different powders and loads I was getting bullets out of one barrel or the other that would have the holes overlapping one-another with two shots from each barrel; Ie, R1 and R2 would be overlapping and L1 and L2 would be overlapping.

Now to the question: For those of you who reload, do you crimp your bullets in place and if so how much of a crimp do you use and what type of crimp do you use, ie, factory crimp, taper crimp, role crimp?

As always, comments, questions and criticisms always welcome.

Kind regards,

Carpediem

I lightly crimp my 600s and 585s using the Lee Factory Crimp Die adjusted to give a light crimp in the cannelure or between bands on banded bullets.

The advantage of the Lee die is jsut what you found - if there is no cannelure or it is in the wrong place for your particular load, it will make one and crimp there.

In other calibers I can't say that I put a crimp in. On those occasions that I do, it is using regular seating die (usually RCBS but I also like Hornady dies).

In the directions that came with my Lee die (which can only be read using an electron microscope) you can adjust the die to give as little or as much crimp as you want.

Stay well

Yes, and 1 inch groups at 50 yards. Not all rifles are the same so one should experiment with this type of reloading procedure to establish what is necessary for that rifle.

Dutch

As a general rule, I do not crimp my 450/400, 8X57RJS, or my 9.3X74R. I you check rounds in the unfired barrel after firing one barrel, I think you will find that the projectile has not moved.

I follow Butch Searcy's advice and lightly crimp with a Lee factory crimp die.

The Lee crimp die is a great tool. I use them wherever I can.

I lightly crimp (1 to 2 /1000's on the neck diameter) calibers starting from .375 and larger with either a roll crimp or Lee factory crimp die. I prefer the Lee if I have it.

I started doing this after Hornady told me that a light crimp provides an opportunity do get uniform ignition and results in less velocity variance shot to shot in the larger calibers.

My chrono and groups agree with Hornady.

I light crimp always. on ever caliber i shot

Does Lee make custom crimp dies? I would have liked to have had one when I was loading for my 500NE, but could not find one for that caliber.

quote:

Originally posted by new_guy:
The Lee crimp die is a great tool. I use them wherever I can.

+1

quote:

Does Lee make custom crimp dies?

Absolutely...I have several...applicable here...my .500 NE

Lee will make a crimp die for anyone.

I had to special order my 9.3 factory crimp die. If I remember correctly, including shipping and handling, it was $40.00 or so Cdn.

Kind regards,

Carpediem

Crimping is necessary with calibers having heavy bullets, such as .450, .470, .500, etc., because the fired round can often cause the unfired round to force the bullet out of its seat, but I never found it necessary for calibers shooting lighter weight bullets, such as 8 x57R, up to and including the 9.3x74R and maybe even the .450/.400., as they have never been forced out of seat from recoil, and I have shot thousands of rounds through the years. I believe that NOT crimping on smaller calibers is not necessary, and will increase life span of the brass involved. Crimping on the heavy bullet calibers is necessary, but will decrease life span of brass, especially if deep crimping is done.