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Shoulder bump FL sizer problem

Following my failed attempt to turn the head nut on my Lee 270 win FL sizer and remove the stuck brass, I’am on to a new FL sizer. I can’t seem to bump the shoulder back .001-.002 thousandth. I have the proper Hornady guage and 270 insert, my numbers never change down. I lower the die with several complete turns to the point that my handle only goes half way down. If I raise the die up or try screwing it down my numbers stay practically the same. My initial FL reading stays the same . I can’t bump down.
 
So, what is fired size in question vs SAAMI dwgs max sizes? It's possible to have a small chamber, also possible to have a big die. Relatively easy way to determine if it is the shellholder, is to trim feeeler gages to fit under case, in the shellholder and see if that gets you anywhere, if it does, you can either shave the shellholder or go to the store and measure up some from the lower deck height to the top and see if you can just buy one.
 
4 suggestions. First does the fired(primer removed, brass not sized) case chamber properly?
If so shoulder doesn't need bumping.
Second, set the die up in the press following the die brand instructions, gutted(no decapping rod/expander button)
Third, use correct shellholder from the die manufacturer.
#4 call the die manufacturer if you still can't size a case properly after following the instructions.
 
You might want to think about getting the Redding Competition Shellholder set???

Those go the other way - 0 = 0.125", 002 = 0.127", 004 = 0.129", etc. Helpful if your die goes too far. I took a set of these holders and put them on a surface grinder and now have a set that goes negative in ~0.0006" steps, so 0.1244", 0.1238", 0.1231", 0.1226" so that when I can't get the bump I'm looking for, even with annealing, I can push past the spring back point.
These are also an option and within a couple tenths of indicated height if not dead nuts on. https://www.amazon.com/DERRACO-ENGINEERING-6pcs-300WIN-MAG/dp/B0DH8F4JZK?tag=accuratescom-20
 
Following my failed attempt to turn the head nut on my Lee 270 win FL sizer and remove the stuck brass, I’am on to a new FL sizer. I can’t seem to bump the shoulder back .001-.002 thousandth. I have the proper Hornady guage and 270 insert, my numbers never change down. I lower the die with several complete turns to the point that my handle only goes half way down. If I raise the die up or try screwing it down my numbers stay practically the same. My initial FL reading stays the same . I can’t bump down.

How many times have the cases that you are trying to size been fired?
2-3 times. Norma brass.
 
I can’t bump down.
Because the brass has not expanded to the chamber.

Starting loads of slow burn rate powders, can cause the case body to expand outward. This can pull the shoulder back. Nothing to bump.

Size fired brass with a gap of .005" between shell holder & FL die. Continue firing same brass, till there is a crush fit when closing the bolt.
IF needed reduce gap .002" more, to easly close the bolt.
 
4 suggestions. First does the fired(primer removed, brass not sized) case chamber properly?
If so shoulder doesn't need bumping.
Second, set the die up in the press following the die brand instructions, gutted(no decapping rod/expander button)
Third, use correct shellholder from the die manufacturer.
#4 call the die manufacturer if you still can't size a case properly after following the instructions.
Yes, fired brass chambers with very little resistance.
 
I've had that happen occasionally with LC 223 brass after several firings/resizings, which work-harden the brass and make it more springy. For me, annealing the necks/shoulders restored the shoulder-bumping effectiveness of my setup/routine without me needing to change anything else.
 
Because the brass has not expanded to the chamber.

Starting loads of slow burn rate powders, can cause the case body to expand outward. This can pull the shoulder back. Nothing to bump.

Size fired brass with a gap of .005" between shell holder & FL die. Continue firing same brass, till there is a crush fit when closing the bolt.
IF needed reduce gap .002" more, to easly close the bolt.
I may be worried about a problem that I don’t have. I may resize and start shooting.Thanks.
 
Yes. I’am having the same results with an Rcbs die to.
I've experienced once with a Redding die that even with the shellholder touching the die on sizing, the shoulder was not moved back far enough. When I changed to a Lee die, the problem went away.

You have the same problem with two makes of die, so put the dies aside for a while and do other checks.

Have you ever successfully sized brass for this rifle ?

If not, and it's a "new" to you rifle, before you do gymnastics with the dies and shellholders, it's worth the time to get a go gauge for the caliber, and see if it chambers.

While you wait for the gauge, do a chamber cast [ you can use elemental sulphur mixed with 10% graphite powder ] and compare what comes out to the brass.
 

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