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How to identify donuts

expiper, my comment isn't directed at you, it is about what you shared. I often see the comment to see if a bullet will slip into the case neck of a fired case. My experience is that it rarely happens. The reason being the mouth of the case doesn't fully open as the rest of the case neck does. For example, my loaded 25-06 rounds neck OD is 0.282", the neck after firing is 0.290" OD. And this is how far a bullet will go into the fired case neck. A near max load.

View attachment 1059738
It depends on the neck clearance. Most of my rifles allow for a slip fit of the bullet in a fired case. One, a very tight neck, does not require neck sizing at all.
 
K&M sells expander mandrels that are available in .0005 increments. You can buy them individually or in a full set. If you are concerned about neck tension and RO, these mandrels are the cat’s ass. The expander mandrel is my last step before priming, powder and bullet seating. Using a hydro press for bullet seating is my method for measuring consistent neck tension.
Ben

i have that kit and agree wholeheartedly
 
I have a couple of questions for you out of curiosity. What is your uses for this rifle? Hunting, strictly target or combination. What is the neck diameter of your chamber? .012 neck would give a .308 loaded round, for a .312 chamber. Since you said that your new to neck turning, I wanted to check that you understood.004 clearance is total, not per side. Also if this is a hunting rifle, I wouldn't recommend jamming bullets. When I read 7RM, I don't think target use. That is why I thought that I would ask.
 
If you cant slip a bullet in a fired case theres 2 reasons: either the brass is too long and needs trimmed or you dont have enough neck clearance. It doesnt matter the barrel or chamber if its right a bullet will slip in and either fall into the case or hit the donut. As far as expander dies go forget the high dollar k&m or sinclair get you a porter precision products die that takes $3 gage pins you can get in any size down to the .0001
 
As far as expander dies go forget the high dollar k&m or sinclair get you a porter precision products die that takes $3 gage pins you can get in any size down to the .0001
I have a many several hundred collection of pin gages, but they would need to have tapers added to become expanders. The MIC Vermont brand are cheap enough, bought singly or in sets on Ebay. One needs to be aware of the tolerance class and "plus/minus" designations. Since I got pin gages, I've found no end of uses for them.
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Can somebody help me out here? I turned case necks to 12k .When seating bullets I can feel inconsistent neck tension. My loading sequence is deprime-anneal-tumble-fl size with honed Forster die. Wash lube off with naaptha - brush necks with nylon brush and imperial graphite expand necks. Also when expanding necks I'm feeling big difference in force it takes to run mandrel through case to case. Even my other calibers I don't neck turn or sort brass in have more consistent seating pressure
 
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Can somebody help me out here? I turned case necks to 12k .When seating bullets I can feel inconsistent neck tension. My loading sequence is deprime-anneal-tumble-fl size with honed Forster die. Wash lube off with naaptha - brush necks with nylon brush and imperial graphite expand necks. Also when expanding necks I'm feeling big difference in force it takes to run mandrel through case to case. Even my other calibers I don't neck turn or sort brass in have more consistent seating pressure
What brand of brass have you?
For which cartridge?
Describe the gun / chamber you're shooting them in.
Describe the honed Forster FL die's dimensions.
Described how you are employing the FL die.

(Err on the side of more rather than fewer details.)
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7mm rem mag - neck turn chamber neck diameter .312. - norma brass -turned to .012 per side so my loaded rounds measure .308-honed die is at .304 and expander mandrel is .281. I'm bumping shoulder back .0015-.002. Fired case neck measures .3105-.311. neck tension was consistent first loading but after first fireing they started to get inconsistent tension
 
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I have Redding type s fl die as well. I've always got better results useing forster fl die. The expander ball is out of my die since I'm useing expanded mandrel
 
7mm rem mag - neck turn chamber neck diameter .312. - norma brass -turned to .012 per side so my loaded rounds measure .308-honed die is at .304 and expander mandrel is .281. I'm bumping shoulder back .0015-.002. Fired case neck measures .3105-.311. neck tension was consistent first loading but after first fireing they started to get inconsistent tension
What brand is your mandrel?
 

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