All my fired brass will not F/L resize

[VEC2]

In a nutshell - I shot about 350 rounds in an AA factory upper, loaded to AA factory approved specs. Gun operated flawlessly, brass looked fine, Accuracy was good. But none of the cases will go all the way through the F/L sizing die. The base of the cases have expanded .014".

I have 3 questions:
1- What could cause this?
2- How can I correct the problem?
3- How can I resize my brass?

Data-
Gun - AA 24" Overwatch upper from AA (2008), Warped flash suppressor from AA
- lower - AA single stage tactical trigger, buffer - A1/A2, 5.9", 5.18oz (146.8g)
w/ 5 ea 18.4g weights and 1 spacer 9.4g. Spring is 12.5' free, 44 coils of .072"
round wire.

Loads - bought lots of AA brass and die set from AA w/ gun. Used reloading table from
AA website. Using new AA brass loaded up several combinations to try. Accuracy
has always been at least 1moa and generally much better. Visually, fired brass
looks fine, No primer flattening, ejector marks, rare dent on a body. So I just kept
shooting my new AA brass. About 350 rounds. Gun runs smoothly and doesn't jump around.

95g H VMax - 31.3g H BL-C(2), CCI-450, 2.200", 2750fps (from table)
108g Scenar - 32.0g H BL-C(2), CCI-450, 2.265", 2730fps (from table)
120g Barnes TSX- 30.8g H BL-C(2), CCI-450, 2.230", 2495fps (from table)
120g Barnes TSX- 30.0g W 748), CCI-450, 2.230", 2503fps (from table)

Went to reload once fired AA brass - vibrating tumbler, went to resize w/ Redding F/L die and would not go the last .25". Die made a large ring of brass at its travel stop. Used Imperial Sizing Die Wax from Redding and RCBS's Resizing Lube. Used 2 Redding F/L Sizing dies one w/ the neck bushing option/ The press is an old RCBS single stage with an RCBS #32 shell holder.

So I measured my once fired Alex-R and compared it to new AA brass:
Base to Shoulder - Fired - n= 45, mean= 1.2155", SD= .00069"
New 1.200". Base to shoulder got .0155 longer.
COL - Fired - n= 98, mean= 1.507", SD= .005"
New - 1.516. COL got .009" shorter.
Base Dia. - Fired- n= 86, mean= .453", SD= .000185"
New - .439". Base diameter grew .014".
Neck OD - Fired - n= 93, mean= .2989", SD= .0004"
New - n= 51, mean= .2877", SD= .0005", Necks got .0112" larger.

Thanx for reading my ramblings.

[m796rider]

Hm. Are you decapping with the die or doing that before using the resizing die?

[VEC2]

I have the decapping rod removed. Just trying to resize.

[Wheelhorse]

Got any good closeup photos?

[VEC2]

Yes, I am trying to figure out how to post a pic.

[VEC2]

Alex-R brass that will not resize

The Redding F/L resize die will only go down 90%. The brass builds up in a ring stopping motion.

Grendel Brass.jpg

[SG4247]

I had the same happen to me yesterday. The brass was from another persons competition Grendel rifle.

This was AA brass also.

I decided he had to have been running a hot load. The same dies have been sizing my fired brass from my guns with no issues.

It is possible your die is "tight". I would shoot some factory loads and see if that brass will resize.

[rwh]

That looks like early unlocking (over gassed) with the case starting to eject while the pressure is still high enough to cause it to balloon out. Did the cases look sooty? The latest thing is an adjustable gas block to reduce the gas pressure and keep the bolt locked a little longer. The old way was to use a heavy buffer.

[VEC2]

I have tried resizing w/ 2 dies. Although both are Redding one is a standard die the other has neck sizing capability.
I listed all my loads - all were from the early AA site and I have seen no over-pressurization issues. I could load up some rounds at the low pressure end of the tables. Might be a good idea, takes longer to drive to the range. Thanx.

RWH - Cases had no soot or blowby anywhere.

[Bwild97]

Can you post pics of fired brass before any attempt at sizing?

Sorry but I have to ask, are you lubing the cases?

[Allen]

Do they have that "belted magnum" look before you resize them? I agree that it looks like early unlocking.

[JASmith]

10 mills growth in diameter is astonishing!

The diameter .02" forward from the base should not be less than 0.433 for unfired brass. Your unfired brass is OK.

The inside diameter of the chamber shoulbe NO LARGER THAN 0.4446 (SAAMI max). Since the distance from the base was not indicated, then we don't know whether measurement was there or on the unsupported part of the case closer to the base.

the earlier posts suggesting esrly unlocking msy have identified the prime suspect.

Can you post a side view of a fired case -- that and the sized cases you already posted will help trouble shoot.

[VEC2]

Grendel Brass 2.jpgPer my post I have tried 2 different case lubes. I have the SAAMI Grendel drawing showing the measurement locations. Case Base OD measurements were taken at max diameter, which is at the point just above where the shell holder grabs (don't know the term). The measuring blade on my caliper is 0.140". Also if you turn the case 90 degrees and measure the diameter axially you get the same max diameter. Thanx

[SG4247]

The base mean diameter of .453" is a little concerning.

As JAS mentioned, where from the base are you measuring that diameter?

I will check some fired brass in the morning.

[lead chucker]

Im no expert, and according to what iv read so far I think you either have a out of spec chamber or resizing die. From what Iv read your saying the fired brass looks normal until you resize it, then you get the ring from the die. That would tell me either the chamber is larger than normal and letting the brass expand more and when resized the die is pushing the excess down while trying to get it back to spec. On the other hand the die is out of spec (to tight) and doing the same thing. I have never seen this happen in 20 years of reloading. Very interesting. I would try another brand of resizing die just to try and rule out the die issue. If it still does it then it must be a chamber issue.