Trying to figure out what is going on with .280 Remington

[postoak]

Are you speaking of Hogpatrol's suggestion of using my Forster sizing die with expander ball removed. Yes, that's wouldn't be good for the reasons you say.

 

[fourfive8]

I'm still confused about the issue (s) asked about here. While rare, there sounds like there may be a very large dimensional difference between the sizing die and the rifle's chamber. One or more of the chamber's dimensions could be at minimum or maximum acceptable and one or more of the die's dimensions could be minimum or maximum. The stars lining up so to speak and the zigs meeting the zags.

The various diameters of the case from the head/web up the body to and including he neck are easy to measure both after firing a full pressure round and after sizing in an individual die. Comparing those two measurements at the various places up the case may reveal out of whack differences between die and chamber.

The headspace datum, which on this cartrdge is the shoulder, is a bit trickier. It is best (and easiest) checked by marking or smoking the shoulder and feeling for resistance and watching for the marked/smoked datum ring around the shoulder left by the chamber after fully cambering a resized round.

The Lee collet neck die usually works very well but it is only a neck sizing die so at some point, if chambering becomes a problem after a few firing cycles, a body die will have to be used. The Lee neck collet die is actually one of the best for minimizing brass work hardening because it only works the neck brass in one direction while maintaining the concentricity between body and neck after sizing. Collet fingers simply squeeze the neck wall inward laterally up against a mandrel that is sized to provide a "standard" amount of neck tension to a bullet. Usually produces very high accuracy potential for reloaded ammo- all other things equal.

If you continue to use a conventional full length sizing die and can make it work with your rifle's chamber then removing the neck button and decapping separately and neck expanding separately usually produces better results, no matter the issues between the chamber and sizing die. The Lyman M die is an excellent neck expanding tool for this purpose and prevents most all the potential issues that may be caused by pulling a neck button out of case under great friction.

So if trying a different brand or type of dies doesn't resolve the issue then the rifle's chamber may be so far out of whack it may be difficult, no matter which method is used for resizing, to find a solution. If that's the case- two solutions 1) have a custom sizing die made for chamber or 2) set back barrel and re-cut chamber.

Who knows, mostly thinking out loud here

 

[postoak]

fourfive8 - let me see if I can make it clearer:

1) Symptom - a much larger than normal force required to press the case into the sizing die and to pull it out of the die. Crumpling of the neck, sometimes, on sizing

2) Over reduction (IMO) of the neck ID


Diagnosis:

1) The Forster (and I suspect Hornady also) dies locate the expander ball differently than other brands. They place it higher and the purpose of this is to provide extra stability and centering of the decapping rod. If the expander ball is positioned "normally", using the extension of the decapping pin as a visual aid, then a condition will arise where the case neck walls are "trapped" between the expander ball and the inner walls of the die. This caused the excessive force requirement AND the neck crumpling I was experiencing.

2) The amount the neck is reduced in OD has to be great enough to handle different wall thicknesses. With thicker than normal case walls, this will result in an excessively small ID. The case walls on my Norma brass are .015" which the Forster Tech Support person said was slightly thicker than normal.

My solution:

Use a body die and collet neck sizing die instead of the Forster die.

 

[fourfive8]

Thanks!, I think I’ve got a better idea about the problem(s). Having to use that much force to resize the neck points to the neck chamber dimensions being very large or even out of spec. If the brass neck wall is a tad thick then yes greater than normal force may be needed for button extraction. Neck brushing with a dry lube can help. Three causes for neck walls to be or to become too thick- Multiple firings/cycles will thicken neck walls. Forming case from larger caliber will result in thick walls. Case manufactured (drawn) from thick stock. Also the symptoms of difficult resizing/expanding will be amplified as each resizing work hardens the brass.

I once had a rifle causing similar symptoms you describe. I just lived with it by modifying reloading techniques. Shot OK but never was a “tack driver”. Besides the basic accuracy being so so, the biggest downside was it shortened brass life expectancy. Coincidentally it too was a 7mm but in 7x57.

If the root cause is something like excessive neck wall thickness,
that would be the best cause!... easily remedied with some different brass.

Anyway good luck and most interested in the outcome or results using the different dies.

 

[C.W. Richter]

I wonder if the people who had problems with Hornady dies crumpling necks had the same issue. I'm too lazy to research to see if Hornady expander balls have to be positioned in this same way.

I've experienced problems with Hdy dies in the past (esp. on larger, 338/.358/375/458 cases). Also cheap components, bending, breakage, etc. Pretty red plastic cases. Like their bullets. Redding, RCBS, Lee (using locking RCBS rings!!!)

 

[postoak]

I was looking around and found this post on another forum:

My memory may be off on this, but here goes. Forster dies have their expander balls mounted high so that the bottom of the neck begins to expand while the very top is still coming out of the neck portion of the die. This is to help case runout. The problem that you may be running into is that the friction of the expander may be adding to the force it takes to size the neck down smaller as it enters the neck part of the die, collapsing the shoulder from the total load. Also, not all expanders are shaped to work well bottom up. The best way to handle this is to use an expander die and mandrel, like you would use to prep cases for neck turning. Forster will lap out the ID of the neck part of their dies for a small fee if your necks are being sized excessively before or in this case after expanding. Like I said, this is all from 20 year old memory, so it may be worth exactly what it cost. If you can lower the expander , reshape and polish the bottom contour, it might be made to work. Just remember to set the die high enough so that the mandrel does not run into the bottom of the case, and put everything back were it is supposed to be once you have done the necks of the new cases. Beyond this, you need to be lubing the inside of the necks and making sure the chamfers are right.

So apparently Forster has been making their dies like this for 20 years.

 

[Bob Nelson 35Whelen]

I bought some Norma cases and FL resized them with Forster sizing dies, mainly to make the mouths circular. Then I fired the loaded rounds. Today, I started resizing with the die adjusted 1/4 turn past touching the shellholder. Holy cow, I've never had to use so much force to get the case into and out of the die. (I used graphite inside the neck, and Imperial Sizing Wax on the outside of the case. The shoulders were not set back at all but there was a bright ring on the shoulder where it meets the neck. (These were not super high pressure loads, BTW). The case length increased to .020 - .025 inches over maximum. Finally, on one especially difficult case the neck collapsed about 2/3rds of the way down. I think I'll probably have to toss these cases. Anyway, I removed the decapper/expander ball and sized a case and there was still a lot of pressure required, although not as much, and the ring at the front of the shoulder remained. The ID of the necks were .275. The expander ball measures .284 inch. The case wall thickness is .015", which seems about right.

I feel like we have discussed a similar problem on a different caliber but can't remember how that was resolved. My first thought was to buy a Lee collet style neck sizing die but this is a special order and Lee is so busy they have suspended special order work, so that is out.

Any thoughts? Should I get Forster involved?

@postoak
You have your die adjustment way to far down. It is recommended to just touch the shell holder then back off quarter to half a turn. Resize the case and try to chamber. If it is hard to chamber screw the die in a bit at a time until you get a slight bit if pressure on closing the bolt.
The way you are doing it you run the risk of bumping the shoulder back to much increasing the head space to possible dangerous levels or crushing the case as you have discovered. The bright doing on the shoulder is caused by the die.
Back your die off and start again.
Bob

 

[Bob Nelson 35Whelen]

I'll be contacting Forster later this morning. I'll probably wind up buying their bushing-bump die. I don't like the idea of those as much as the Lee Collet die, OTOH, it also sizes the body at the same time.

1) CBH - the dies are not new. I used them on the 100 new cases I had purchased to true up the mouths. (I wish I could remember if there was excess force required when I did that, but at least I know it wasn't enough to catch my attention.)

1) Pheroze, that 1/4 turn past the stop is getting me NO set back.

2) I agree Bruce, .275 sounds way too small to me, or at least way more than I like. I think those old posts I vaguely recall involved Hornady dies that oversized the neck.

One possibility that occurred to me is that I have an oversized chamber, but I just measured and the dies are reducing the bulge in front of the web just .003" and reducing the shoulder diameter .007". Neither of these seem excessive to me.

@postoak
.275 isn't to small remember you did this WITHOUT the expander and so only necked the case.
Replacing the expander ball will bring it back to the correct diameter. You should be able to get a carbide expander ball at .281. This will give you a neck tension of .003 tho which should be ideal.
Bob.
Yes Lee collet dies are good I have a few of them.

 

[Bob Nelson 35Whelen]

I wonder if the people who had problems with Hornady dies crumpling necks had the same issue. I'm too lazy to research to see if Hornady expander balls have to be positioned in this same way.

@postoak
That's why I like Lee dies they have a tapered expander no balls to worry about.
With the tapered expander I have necked up 270 brass to 35 Whelen for the fun of it in one pass and the neck lube with graphite.
Bov