too much shoulder bump and using mandrel

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flatsticks

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What would you do with your brass if you bumped the shooulder back too much by accident.

Sized some brass of a different headstamp and it bumped the shoulder back 2-3 thousands more than

it did on my previous brass .

It is for my 556 and I had been in the 4-5 thousands on my previous batch , now it has been bumped back 6-8 thousands .

Did not notice it until I had about 75 cases done , should have checked after a couple .... lesson lerned .

Second question what and how do you lube your mandel for neck tension on new brass .

Thanks
 
Really depends on how many times those cases have been reloaded previous. If this was the 7th loading I would probably skip anything further and just toss them, but that's me. If they are only on their 2nd loading and you can honestly say the worst case hasn't had the shoulder bumped back more than .009" then if it were me I'd load em up and shoot em. Caveat being I'd separate those cases and watch them carefully, might have to toss them.
 
I had cases that needed trimming and some didn't. They are all different. I was just listening to a gunsmith on brass and memory. He said start with new brass and shoot it in your rifle. IDK? I have shoulders that measure different headspace, I check them all as I sized them. I have brass from where ever, and well, they're all different, same manufacture but different lots. From time to time I have to move my die, but most of the time no. Make sure your die is clean.

I recently starting using Burts Bees lip balm. Use sparingly on the mandrel, and I have many cases that size really well. Just run the stuff over your finger lightly, rub your thumb and forefinger together and apply evenly on the mandrel. I rotate the case few times 1/3 rotation and check for springback over my turning pilot. I could use a .3075 rather than a .307 to prevent the three times running through the mandrel. 21st Century Pete told me I that I would be better off. I forget the amount of spring back but I would have to do as much maybe just the one time. We'll see.
 
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@Walkalong got it. Assuming none have incipient separations, load and fire. Likely some will have incipient separations thereafter, and some won't.
 
The brass is lake city and was fired once in my gun.

I asked about the lube on tne mandrel as I tried it on few new 6.5 cases and it was not smooth on the return trip even with a little lube on the mandrel ( maybe not enough )
 
flatsticks said:
The brass is lake city and was fired once in my gun.

I asked about the lube on tne mandrel as I tried it on few new 6.5 cases and it was not smooth on the return trip even with a little lube on the mandrel ( maybe not enough )
Click to expand...
Some people use the redding graphite so the cases dont need cleaning. It's my last step before bullet and powder. You can get carbide mandrels but knowing what size you want first before dropping 60 bucks.
 
flatsticks said:
The brass is lake city and was fired once in my gun.

I asked about the lube on tne mandrel as I tried it on few new 6.5 cases and it was not smooth on the return trip even with a little lube on the mandrel ( maybe not enough )
Click to expand...

Or maybe too much. I use Burts Bees very sparingly. Lip balm stick. Run it across your finger lightly an rub thumb and forefinger together and coat mandrel. I see the word carbide mandrels.... and it escaped me, till now !! Sounds like a better deal.
 
Help me figure out what I’m missing. Using the Wilson case gauge:
Factory new brass- 1.760
Fired in gun 1- 1.768
Fired in gun 2- 1.771
I normally bump the shoulder to 1.765, but have had many bump back farther, and never had an issue with feeding or head separation and I commonly see the advice to full length resize for semis which would bring me back to 1.760.
I’m not sure I understand the abundance of caution call to scrap the brass or even keeping a watchful eye after an .008 bump. The case is handled a lot during the case prep stage where it’s usually not a problem to find a flaw.
 
If your not annealing your brass, the different hardness along can give you a pretty good variation. This is why I anneal every time. Keeps every thing the ssme and more consistent. If I'm using a mandrel or only neck sizing I use the Imperial neck sizing lube ( mica/graphite). This does not need to be cleaned off after wards.
 
MakBaba said:
Help me figure out what I’m missing. Using the Wilson case gauge:
Factory new brass- 1.760
Fired in gun 1- 1.768
Fired in gun 2- 1.771
I normally bump the shoulder to 1.765, but have had many bump back farther, and never had an issue with feeding or head separation and I commonly see the advice to full length resize for semis which would bring me back to 1.760.
I’m not sure I understand the abundance of caution call to scrap the brass or even keeping a watchful eye after an .008 bump. The case is handled a lot during the case prep stage where it’s usually not a problem to find a flaw.
Click to expand...
Factory new brass or ammo has to fit into any proper SAMMI chamber, which means it has to fit a SAMMI minimum chamber, so it is generally shorter base to datum (Middle of shoulder) than our reloads.

For good brass I generally get a .001 spread on the base to datum/shoulder measurement. An example, using my Sinclair tool for getting
a measurement on sized cases in 6 Creed. Gauges like this give us an arbitrary number of course, it's only useful compared to its self.
Sizing 6 Creed - Before @ 75%.JPG Sizing 6 Creed - After @ 75%.JPG

.008/.009 is simply too much head clearance, which acts just like too much headspace machined into a chamber. In other words,
we took a perfectly good chamber with allowable headspace/head clearance with proper ammo, and we created artificial headspace
in the form of too much head clearance and created a dangerous situation just as if the rifle had improper headspace. Too much
room for the case to stretch. Since we control sizing, why would we want to do this? Yes, we very well might catch the internal rut
after firing and before we size/shoot it again, but it might separate on us when shooting it instead, and since we know how to avoid this,
we should.

https://www.thehighroad.org/index.php?threads/incipient-case-head-separation.734058/
 
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SEPARATIONS- At .014" i had separations in the 5.56/223 case body. Scraped about 250 brass. At 008" i would reload and watch for the first sign of pending sepatation, a thin bright line. If 1 separation is seen starting, the whole lot gets scraped.

EXPANDER- Standard die set expanders can be almost impossible to pull back out of a sized 223/5.56 brass neck on some brands of brass. Lubes dont really help much on the problem brass.
Even new brass may have a donut, causing the extraction problem.
I fix it by neck turning and annealing 1 time. Then use my standard RCBS fl die to size. This greatly reduces split necks & extends brass life.

Dillon users- check FL sizing, shoulder bump from each station. The shell plate may have issues.
 
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My Dasher cases usually measure +.001 or +.002 on this Whidden tool after firing. I sized them to measure about -.001 or .000, but a couple of them were +.001. No issues though, since +.002 still chambers. Remember, cases spring back a little after firing. I don't cut it this close for semis.
For 300 BLK I move shoulders .002 to .003. No issues. For .223 I size to fit my Wilson or Sheridan case gauge. No issues there either, with great
case life and no signs of a rut even after up to 12+ firings.
Whidden 6 Dasher Case Guage @ 50%.JPG
 
Walkalong said:
Factory new brass or ammo has to fit into any proper SAMMI chamber, which means it has to fit a SAMMI minimum chamber, so it is generally shorter base to datum (Middle of shoulder) than our reloads.
Click to expand...
Very true.

Fired some 30-30 factory ammo that stretched .022" without issue.
Here the annealing, brass quality makes a difference.

The 5.56 ammo is processed on high speed machines. Its made to be fired 1 time. If any 1 step in the manufacturing process can be skipped, it is.
Less anealling is the first step to speed up the process. Or even 1 draw process.

Example- Winchester Nato 5.56 ammo had case head separation in a non-M 16 brand Nato rifle. The action timing was different then our M16. Winchester needed to anneal the neck/shoulder 1 more time to stress relieve the case body. Stress relief happens around 400F on the case body. Neck is hotter.
https://discover.dtic.mil/
 
Appreciate the information , as always I learn a lot reding there .

I pretty much figured I would be tossing the brass but just wanted to be sure .

No sense creating any unsafe conditions .

On a positive note I sized the brass before working on the military crimp and I have a lot more of that LC brass that was once fired to replace it .

Thank you all !
 
Think I am going to pick up a micrometer for seating my 6.5 bullets . will be more careful to check on my next batch of 223 that I size looking at the first couple and make adjustments from there . die was fine for another headstamp made a rookie mistake but assuming the LC brass would turn out the same . we learn from our mistakes just glad I have more to replace it with .
 
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