Caming press

timmymic

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Sep 23, 2012
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Was watching a long range only video where he was setting up his dies and was caming over both the seating die and the sizing die. I have never done this before. What are others doing? I am trying to find a way to get my reloads more consistent. I typically have very little variations then randomly I will have a COAL that is outside the norm but my process feels the same so I am unsure what is causing it. THinking if I use the caming method that may take this away. Thoughts?
 

243winxb

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First measure case head to bullet ogive for a COL.

When shell holders contact the botton of dies, this acts as a stop. Removes the effect from sloppy single stage press linkage.

To control shoulder setback while fl sizing, use Reddings Competition Shell holder set. These shell holders will make a longer head to datum/shoulder measurement.

Redding Competition seat die can lightly touch the shell holder. (See Reddings website)

Lee makes a Dead Length Bullet seater that makes contact with the shell holder.
 

LoneTraveler

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Cam the press over center and adjust the die to give you the shoulder setback you want. Some dies use the shell holder height to give perfect shoulder set back.

With some makes of dies, Be careful. Put an empty sized shell in shell holder and screw the die down till it touches the case, As the press cams over, Then back the die off 1/2 turn. This will keep the case neck from touching the crimp bevel in the die.
If the case hits the crimping bevel, Not set proper for crimping, It can put a lump at the body/shoulder junction and will cause chambering problems.
 

MagnumManiac

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Feb 25, 2008
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I never have the seater die touching the shell holder on conventional die sets. As mentioned above, the crimp feature will touch the case mouth doing so.
My comp seaters (Redding/Forster) have a sleeve that contacts the shell holder, but the die body itself does not when the shell holder is at the top of the stroke.
I wonder what seater die can be cammed over on most presses...has me baffled.

Cheers.
 

AZShooter

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If your attempt is to take out the "slop" in the coarse 7/8" x 14 threads of die and square it up, you could cam with a parallel in between shell holder and die face Would think that would have the same effect yet leave you some space.
 

FEENIX

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Was watching a long range only video where he was setting up his dies and was caming over both the seating die and the sizing die. I have never done this before. What are others doing? I am trying to find a way to get my reloads more consistent. I typically have very little variations then randomly I will have a COAL that is outside the norm but my process feels the same so I am unsure what is causing it. THinking if I use the caming method that may take this away. Thoughts?
I have done similar to the video you are referring but I do not know if "I" can claim consistency on my "actual" method due to caming as supposed to the overall reloading process. He has better set up than mine and I think that's an advantage. Perhaps I need to explore more next time ...
 
D

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Some presses are designed to cam over, some not.

Camming over will wreck a Lee collet die.

I only do it if a case will not chamber.

Redding neck bushing dies are easier on the case and the press.

For hunting, I use new fully prepped brass or new Nosler if available. No problems, no surprises.
 

MagnumManiac

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The purpose of cramming over is to get CONSISTENCY.
It take out all the slop in the linkages and acts as a physical stop so that each piece of brass is sized exactly the same.
Some brass will resist the sizing forces more than others and if the slop in the linkage is not taken out then sizing between cases will be different.
My Forster dies just kiss the shell holder and I can get a whole batch of brass (200) to have no more than .0005” runout and be within .001” of the desired head to shoulder length. Obviously annealing after each firing helps this too.
I don’t try to get this amount, as I discovered years ago now that runout means very little on a chamber/action assembly that is plumb and square to the bolt/barrel/bore centreline.
Even my RCBS dies just kiss the shell holder when sizing, if I have to modify them or the shell holder to get the desired cam over, then I do. I also only use honed neck dies these days, as bushing dies in my experience cause donuts.

Cheers.
 

Deputy819

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I wonder what seater die can be cammed over on most presses...has me baffled.
Hey, Tony! My Lee 6.5 Creedmoor seater die ‘cams over’ in my RCBS Rock Chucker Supreme press, oddly enough.....but my Redding seater dies do not. I was quite surprised about that, myself. I’ve pretty much stopped checking each Creedmoor rounds seated for consistency....it’s been dead nuts on.
 
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ButterBean

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My new summit press cams over on all dies, even seater's and lee collet dies. Designed to and perform's well, especially keeping rounds concentric in all steps.
I agree with you on the concentrically and I could set mine up to cam over on the seater but I don't, just personal preference , camming over on the Lee Collet Die is great for helping control spring back
 
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