First Indication of a PPU Case Head Separation

Message Topic Search Topic Options Post Reply Create New Topic Printable Version Translate Topic

   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.  

Author	Message Topic Search Topic Options Post Reply Create New Topic Printable Version Translate Topic
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: 4175	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.

Sponsored Links

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: 14800	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: 4175	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: 4003	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.