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Forster full length

Ok guys I bought a forster full length sizing die and it kept crushing my necks with and without the expander ball so I sent it in for them to look at. They sent it back and said I had the expander ball wrong so they redid it. Now I have to screw it down to the shell plate and back it off 1 1/2 turns to make it work but its still bulging the middle of my necks a bit... what am I doing wrong Im still a novice but I havent had a problem with my reddings, hornady, or lees.
 
I have Forster full length dies for every caliber rifle I have, and if the expander is set too high it will cause problems.

If you feel excess resistance when sizing, then the expander is set too high even if there is no damage to the neck. I adjust my expander per the instructions and going by feel and checking the neck for runout. And when expanding the neck is a smooth operation and your case neck has very little neck runout you are good to go.

The case neck should be held and centered in the neck of the die when the expander enters the case neck. And if the expander is set too high it tries to expand the neck when it is too close to the neck of the die. All you need is for the very top of the case mouth to be held and centered in the neck of the die when the expander enters the case neck. This centers the floating expander and keeps it from pulling the neck off center and inducing neck runout. And when the inside of the case neck is lubed the expander should slide through the neck as smooth as silk.

Lower your expander 2 or 3 turns and you should feel and see a difference when expanding.

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I sent it to them with some brass I had and they set the expander ball to there standards and resized them. Then when I tried it caused this.
 
I sent it to them with some brass I had and they set the expander ball to there standards and resized them. Then when I tried it caused this.

Lower the expander a few turns and see what happens. The purpose of the high mounted floating expander is to reduce neck runout. The worst that will happen if lowered too far is the case neck will not be held and centered in the neck of the die. Meaning the case neck runout "might" increase.

If I was to guess I would say less than 1/4 of the neck is expanded before the case neck comes out of the neck of the die. All that matters is that the expander enters the base of the case neck and the neck is held and centered by the neck of the die.
 
I tossed all my Forster dies in the trash can years ago but I agree with ED- adjust the ball height...
 
Not gonna lie this will be the only ones I buy after all this I wrote them telling them about it while I had it and what setup I had and they just kept blaming me for not doing the expander ball correctly so there went $12 for shipping... heard great things about them so I wanted to try but Im not impressed
 
How much are you bumping the shoulder back when sizing? Backing the die off the shell holder ~0.090" seems like a lot. I set my dies by shoulder bump, most of mine end up around .020"-.050" off the shell holder. My point is the die may be too high and not sizing the entire neck.
 
The only way I can even size them is by backing it off that much or it crush's the necks. I didnt even measure the shoulder bump I got sick of screwing with it and loaded some 6.5. I will get a measurement this evening
 
I use a honed Forster and have to say it's the best die I've used. Even using it locked down (no O ring) in a Dillon toolhead, I get less than .001 RO. The expander can be set very low and still not create any more runout. That brass looks like the expander is coming back through the neck as too much of the case neck is still in the sizer. Try lowering the expander more than you think you should. Just my .02...

Edit: Crushed necks could be a lube issue. The Forster's I've used would not oversize; I had them shorten all of mine by a couple of thousandths to allow sizing without excessive cam.
 
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Is your chamber possible large and the die is trying to size the neck down more than it needs. I just got a new set and set to instructions and no problems at all.
 
I’ve been trying to mimic your results with my Forester dies that aren’t honed. They all size properly.
 
Well I played with the expander ball for an hour going down half a turn at a time and got it to where it wasnt doin it as bad but still bulged the neck around 3 thousandths... Im done screwing with it
 

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