First Indication of a PPU Case Head Separation

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   I have my first indication of an incipient case head separation in my first batch of PPU cases.
Unfortunately I have not logged the number of reloads, I suspect 30+, perhaps over 40.  Had to get the lighting just right for it to show in the photo below.   It does not look nearly this obvious in normal lighting. 

This was on the first firing after a partial length resize (I think I’ve P/L resized these cases three times now, typically get 10 to 15 neck sizing reloads between each P/L resize).  I shot this on Friday at the D-Day match.  I like to have the cases P/L sized for a major match, as it makes bolt cycling and lockup very fast for the rapid fire stage. 

I’ve been tracking the number of reloads in subsequent batches and now at 15 neck sizings and one partial length resize.  

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britrifles Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: February 03 2018 Location: Atlanta, GA Status: Offline Points: 5591	Post Options Post Reply Quote britrifles Report Post Thanks(0) Quote Reply Topic: First Indication of a PPU Case Head Separation Posted: June 12 2022 at 8:15am
	I have my first indication of an incipient case head separation in my first batch of PPU cases. Unfortunately I have not logged the number of reloads, I suspect 30+, perhaps over 40. Had to get the lighting just right for it to show in the photo below. It does not look nearly this obvious in normal lighting. This was on the first firing after a partial length resize (I think I’ve P/L resized these cases three times now, typically get 10 to 15 neck sizing reloads between each P/L resize). I shot this on Friday at the D-Day match. I like to have the cases P/L sized for a major match, as it makes bolt cycling and lockup very fast for the rapid fire stage. I’ve been tracking the number of reloads in subsequent batches and now at 15 neck sizings and one partial length resize.

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Shamu Members Profile Send Private Message Find Members Posts Add to Buddy List Admin Group Logo Designer / Donating Member Joined: April 25 2007 Location: MD, USA. Status: Offline Points: 16520	Post Options Post Reply Quote Shamu Report Post Thanks(0) Quote Reply Posted: June 12 2022 at 12:13pm
	Yep that's the classic symptom!
	Don't shoot till you see the whites of their thighs. (Unofficial motto of the Royal Air Force)

britrifles Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: February 03 2018 Location: Atlanta, GA Status: Offline Points: 5591	Post Options Post Reply Quote britrifles Report Post Thanks(0) Quote Reply Posted: June 12 2022 at 1:39pm
	That area of the case just forward of the head undergoes a lot of plastic strain, and thins the brass. I can see it getting thin looking down the case mouth, the thin area will be in shadow if you shine a light down into the case. Hate to junk this whole batch, but that’s probably what I should do.

Honkytonk Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: December 30 2017 Location: Brandon Mb Status: Offline Points: 4613	Post Options Post Reply Quote Honkytonk Report Post Thanks(0) Quote Reply Posted: June 12 2022 at 1:54pm
	Might just be a weak one in the batch but probably binning the rest of that batch is the way to go.

Breaker Members Profile Send Private Message Find Members Posts Add to Buddy List Groupie Joined: July 21 2022 Location: APPALACHIA Status: Offline Points: 20	Post Options Post Reply Quote Breaker Report Post Thanks(0) Quote Reply Posted: July 23 2022 at 9:00am
	I wouldn't toss out the others from that batch, but downgrade them to low pressure cast round ball loads. they could last many more shots at that level of pressure. Thats just my practice when brass gets to this point and may not be for everyone. Those certainly lasted through many loadings already!

A square 10 Members Profile Send Private Message Find Members Posts Add to Buddy List Special Member Donating Member Joined: December 12 2006 Location: MN , USA Status: Offline Points: 13701	Post Options Post Reply Quote A square 10 Report Post Thanks(0) Quote Reply Posted: July 24 2022 at 7:24pm
	breaker - welcome if ive not said it before , i think you are addressing reloaders that dont soot the low pressure loads you mention often , i do and understand where your going with this , but unless that fits their shooting patterns it wont help them much , maybe they have friends that do they could give these to , it is a good way to salvage these for an extended life use ,

britrifles Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: February 03 2018 Location: Atlanta, GA Status: Offline Points: 5591	Post Options Post Reply Quote britrifles Report Post Thanks(0) Quote Reply Posted: July 25 2022 at 7:06am
	My typical approach is to cull the cases that show the white line as an impending case head separation. The lot eventually gets down to less than 40 cases at which point I throw the remaining cases in the scrap container. I try not to mix in new cases with old cases.

DaveNo5 Members Profile Send Private Message Find Members Posts Add to Buddy List Groupie Joined: January 15 2022 Location: Western NY, USA Status: Offline Points: 82	Post Options Post Reply Quote DaveNo5 Report Post Thanks(0) Quote Reply Posted: July 25 2022 at 9:41am
	If you're going to discard it, could you section it with a hacksaw to see the extent of the wall thinning? I am curious as to what it looks like inside. Dave
	DaveNo5

Shamu Members Profile Send Private Message Find Members Posts Add to Buddy List Admin Group Logo Designer / Donating Member Joined: April 25 2007 Location: MD, USA. Status: Offline Points: 16520	Post Options Post Reply Quote Shamu Report Post Thanks(0) Quote Reply Posted: July 25 2022 at 11:42am
	Here you go. I crushed the case mouths to prevent others fishing them out of the trash at the rage & tying their gun up.
	Don't shoot till you see the whites of their thighs. (Unofficial motto of the Royal Air Force)

britrifles Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: February 03 2018 Location: Atlanta, GA Status: Offline Points: 5591	Post Options Post Reply Quote britrifles Report Post Thanks(0) Quote Reply Posted: July 25 2022 at 11:50am
	Yup, done enough of these to be able to spot the “white line of death”. Mine usually crack a bit lower than the photo Shamu posted, about 5/16 inches up from the bottom of the case head.

Dragunov Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: November 12 2021 Location: Melbourne, FL Status: Offline Points: 196	Post Options Post Reply Quote Dragunov Report Post Thanks(0) Quote Reply Posted: July 25 2022 at 11:58am
	This is why I always keep a broken she!! extractor in the butt trap (just in case).

Shamu Members Profile Send Private Message Find Members Posts Add to Buddy List Admin Group Logo Designer / Donating Member Joined: April 25 2007 Location: MD, USA. Status: Offline Points: 16520	Post Options Post Reply Quote Shamu Report Post Thanks(0) Quote Reply Posted: July 25 2022 at 2:09pm
	I've had a couple go there. This odd positioning seems unique to the Remington nickle-plated I got a bunch of years back.
	Don't shoot till you see the whites of their thighs. (Unofficial motto of the Royal Air Force)

A square 10 Members Profile Send Private Message Find Members Posts Add to Buddy List Special Member Donating Member Joined: December 12 2006 Location: MN , USA Status: Offline Points: 13701	Post Options Post Reply Quote A square 10 Report Post Thanks(0) Quote Reply Posted: July 25 2022 at 9:18pm
	wow , thanks for doing that it really brings home what is happening in there - photo/1000 words kinda thing

britrifles Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: February 03 2018 Location: Atlanta, GA Status: Offline Points: 5591	Post Options Post Reply Quote britrifles Report Post Thanks(0) Quote Reply Posted: July 26 2022 at 4:28am
	Here’s what mine look like. The progression of case web thinning (far right), and left to right, the “white line of death”, visible cracking and head separation. These happen to be Canadian DI Mk 7 cases, with 40+ reloads.

Dragunov Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: November 12 2021 Location: Melbourne, FL Status: Offline Points: 196	Post Options Post Reply Quote Dragunov Report Post Thanks(0) Quote Reply Posted: July 26 2022 at 5:12am
	Britrifles, could you share your load with us? I use mostly PPU brass with IMR 4064 (39 grains) as my "go to" with both 180 JSPs and 174 FMJs. But, even neck sizing only, 10 reloads is about the end of the world for me. Perhaps it is my particular rifles chamber?

britrifles Members Profile Send Private Message Find Members Posts Add to Buddy List Senior Member Joined: February 03 2018 Location: Atlanta, GA Status: Offline Points: 5591	Post Options Post Reply Quote britrifles Report Post Thanks(0) Quote Reply Posted: July 26 2022 at 7:52am
	My match load is PPU Case (or Canadian Service Mk VII Ball case), 40.0 gr Varget (ADI AR2208) and 174 grain Sierra Matchking. I think the largest single factor in case life is headspace. That controls how much plastic strain the case experiences in the web area that is unconstrained by the chamber. I keep my rifles at minimum headspace, just over 0.064 inches. None of my rifles will lock up on a 0.070 gage, bolt handles typically half inch from closing on the 0.070 gage. I also think neck sizing is essential to long case life, to keep the case head up against the bolt head. But, you don't want to have excessive force to close the bolt either. Some light pressure on the handle to fully lock the bolt is OK. Just my experience, others may have a different experience...