If I anneal, and trim, resize and reload more than normal, when do I get casehead sep?

[Amanda4461]

Just asking. Coming from mainly pistol reloading, I now reload for .300 Winchester Magnum. My normal process is take my virgin brass, usually Winchester or PPU, place 50 in the loading block and inspect the case mouths. PPU, I find few, if any issues. They are ready to uniform the flash hole, chamfer and deburr. Winchester is cheap and typically availability is good for a reason, the case mouths are out-of-round and I typically find two case necks out of 50 with vertical cuts rendering them useless. Piss-poor QC and their packaging machines, or monkeys, whichever loads the bags of brass, must be rejects from UPS. Brass is always damaged to some extent. I run every WW virgin brass through the expander button, just so that I can chamfer a round, rather than elliptical case mouth. Then the search for the flash hole commences. Again, poor punch alignment QC.
After 4 firings of PPU, I will trim all cases, chamfer and deburr. After 3 firings of Winchester, I will trim all cases, chamfer and deburr. Each fired case is deprimed and pushed into a Lee Collet die. The Collet does fine at depriming and giving me a couple thousandths shoulder bump. I keep my loads below max, typically using a 200gr. SMK and Vihtavouri N-560 2 grains below max, allowing 2800fps. I throw the brass in a bucket after it reaches time for the second trimming, and ignore it. I buy new brass and start the process again.
If I Anneal, how long will it take before the brass that I will end up trimming results in thin brass just ahead of the belt on my brass, and I get to find out what case-head separation is all about? I see the possible shot to shot improvement from annealing, but I would need to test and see enough improvement to decide that it was worthwhile. Annealing to get more caselife would lead me to wonder when the brass would thin too much. Sure, I would like to keep loading past 6 reloads per piece of brass. As is, I get to using my dental pick on the brass, looking for the depressed ring ahead of the belt, after I trim and reload the 4th time with WW, and the 5th time with PPU. Too cautious, I may be, but 55,000psi is a nice hand grenade. Do I feel lucky?
Thanks for all suggestions. Please let me know if I am being chicken little, or pushing the envelope.

 

[supercorndogs]

CHS has little to nothing to do with any of those things. You get CHS generally from bumping the shoulders back too far. With belted mags you eat up a lot of that on the first firing because the chambers are so loose. I have a semi retired box of Winchester 300WM brass with 17 reloads on it.

 

[axarob44]

How are you getting shoulder bump from a Lee collet neck die? It only sizes the neck.

 

[308pirate]

If annealing leads to case head separation in your ammo, you're doing it very wrong.

 

[Gustav7]

If I Anneal, how long will it take before the brass that I will end up trimming results in thin brass just ahead of the belt on my brass, and I get to find out what case-head separation is all about? I see the possible shot to shot improvement from annealing, but I would need to test and see enough improvement to decide that it was worthwhile. Annealing to get more caselife would lead me to wonder when the brass would thin too much. Sure, I would like to keep loading past 6 reloads per piece of brass. As is, I get to using my dental pick on the brass, looking for the depressed ring ahead of the belt, after I trim and reload the 4th time with WW, and the 5th time with PPU. Too cautious, I may be, but 55,000psi is a nice hand grenade. Do I feel lucky?
Thanks for all suggestions. Please let me know if I am being chicken little, or pushing the envelope.

Like others have said, annealing doesn't mess with the case head unless you're annealing the body, but that would go bad quick lol.

If you're 2 full grains under max, then you're not even close to being on the edge of pushing the brass hard, so I wouldn't be worried about case head separation after 4-5 firings, unless you're over sizing too much.

You either have a regular Lee full length sizer and you are thinking its called a Lee Collet Die, or you have LCD and you're not sizing your shoulders back at all. Are you using calipers and a comparator to measure your shoulder bump?

Also, generally speaking, a case head separation isn't going to "grenade" your barrel/action.

 

[Amanda4461]

How are you getting shoulder bump from a Lee collet neck die? It only sizes the neck.

Unless my Forster collimator is being read wrong, the shoulders show the bump after the die has been screwed down a couple of rounds in the co-ax. I’ll measure some new brass after it’s first firing today, and after it goes through the collet die, and make sure it just isn’t my imagination. I know that the force required to get the co-ax to full travel is more than it takes to run my Valkyrie cases through their sb sizer die. Still wondering where all this brass is flowing from, for those who reload belted magnums more than 6 or 7 times? I probably need to section a case for verification every so many reloads, just to see the effects. I have plenty of time, may as well cut a few cases open.

 

[supercorndogs]

Brass flows when you are way over pressure. Brass flowing is not what causes CHS. Brass stretching at the web causes it to get thin, which leads to CHS.

 

[308pirate]

Also, generally speaking, a case head separation isn't going to "grenade" your barrel/action.

I had two yesterday with shit Winchester brass that went in the trash as soon as I got home. Nothing unusual except a slightly sticky bolt.

 

[Steel head]

If your initial case stretch and subsequent resizing is minimal you’ll probably lose the primer pocket well before a case separation.
I scrapped a lot of brass after I had a case separation earlier his year.
Winchester brass had over 40 firings on it.
I had already culled a lot of that because of opened up pockets.

 

[TxWelder35]

I lost the primer pockets on hornady 300wm brass at 7 firing with a stiff load

 

[axarob44]

If your initial case stretch and subsequent resizing is minimal you’ll probably lose the primer pocket well before a case separation.
I scrapped a lot of brass after I had a case separation earlier his year.
Winchester brass had over 40 firings on it.
I had already culled a lot of that because of opened up pockets.

Over 40 firings?

 

[Steel head]

Over 40 firings?

That lot of brass killed 2 and almost a third 260 barrels.

 

[Amanda4461]

The rest of the story: Loaded 50 virgin W-W .300 Winmag brass. Chrono showed 2893fps for the 190gr SMK’s I had available. SD=7. ES=24. Checked my 30 year old Starret dial calipers against a 1” standard. Repeatability was poor and off several thousandths. Started up a new Mitutoyo. Seems like I forgot the Neck Size step after the Lee Collet die. Axarob44, good catch. The Lee doesn’t do anything but allow me to punch out primers and reduce the Neck O.D. from 0.3375” to 0.3305” without using any lube. I use a Redding Neck Sizing die, without the expander stem. CB-Shoulder after firing = 2.2750”. CB-Shoulder after Neck Sizing = 2.2740”. I get only 0.0010” setback, with the Neck die screwed quite far down near the shell plate on the co-ax. Regardless, at this point, I normally tumble, then prime and load them up. Today, after seeing what appears to be minimal shoulder bump, I Full Length sized after Neck Sizing. The COAL increased to 2.620” from the 2.6175” that it was after Neck sizing. The CB-Shoulder increased from 2.2740” to 2.2765”. Seems like my CB-Shoulder actually increased by 0.0025”. Seems like I need to stick with Neck Sizing, and be happy with the 0.0010” setback on the shoulder. Another plus is the Neck O.D. Is reduced in that neck die down to 0.3260. I believe I could just forget the Collet die and stick the expander/decamped rod back into the Neck die and save a step, unless using the Collet first helps the uniformity of the neck. Anything I am doing wrong, please step up and let me have it.
Thanks!

 

[Gustav7]

Sounds like your full length die isn't screwed down far enough. I've done that before when I switched from a turret press to a Dillon... the setup on the two presses is wildly different and the Dillon I don't cam over, so i was a little confused when my cases grew.

How did you set up your full length die?

Also... am I reading this right that you're using a Lee Collet Die AND a Redding Neck sizing die? .... cause those do the same exact thing lol. If thats right, then stop using one of them.

Either use a Lee Collet and then FL size every other or every 2 firings..... OR, just use a FL die and decap, neck size, and bump the shoulders all in one motion.

 

[lash]

When you full length resize, you are moving brass. It has to go somewhere, and that somewhere is oal. Not uncommon at all. If you want to reduce headspace by 001.-002” then you need to continue to lower your full-length sizing die until you do so.

Also, if you still plan on neck sizing, do it after you have properly full-length sized and have the correct headspace that you need.

 

[Amanda4461]

Thanks for the info. I initially used the Collet die to save time with no lube and no tumbling. My Redding Neck Sizing die came in last week, so I decided to try it after the Collet die, to see if I noticed a dimensional difference. The Redding Neck die appears to do what I want, even if I have to towel off the lube or tumble.
The Full-length die isn’t bottomed out against the co-ax shell plate, so I’ll adjust that die until it gets me the needed bump. Sounds like using the FLS die is what I need to concentrate on, once I get it set correctly. I only shoot steel, and just using the one die will simplify the process. I’ll investigate the affect of just using the neck sizing die if I get to where I can tell a difference on paper.