lancetkenyon Report post Posted November 26, 2017 I run my 7 Rem Mag pushing a 180 Hybrid @ 2996fps. Never any presssure, but on the 8th firing, I finally had a brass failure. I didn't even know this happened yesterday until I went to resize it today. Good thing I have another 349 pieces already loaded. I have been using this first 50 pieces since I started. Always bumped shoulder .002". Check your brass carefully. Even new. I have seen brand new brass with cracked necks, a hole in the shoulder, a split down the side, and a crack at the top of the rim. Share this post Link to post Share on other sites
300RUM Report post Posted November 26, 2017 I frequently get radial cracks like that with federal brass. I got several .50 cal cans of mixed R-P and FC .308 brass off a L/E range master years ago. With the R-P the failure point is consistently a loose primer pocket. With the FC it is a radial crack like that, varying distances from the head. I have not seen many open up like that. I have learned the failure starts from inside the case and works it's way through the wall. To check for weak cases I insert a angled pick and drag it along the inside wall from the head toward the neck. If you feel the pick catch on something it is a crack forming. Share this post Link to post Share on other sites
lancetkenyon Report post Posted November 26, 2017 Yep. I have done the feeler. I have a straightened out paper clip with a bent end I use. I will be checking the other empty brass carefully. Share this post Link to post Share on other sites
lancetkenyon Report post Posted November 26, 2017 I wonder if that was my one flier I had yesterday? All others in the 6 shots I took were within .5" @ 200. I had one flier that was about 3/4" out from the group. We will blame the flier on this....sounds good to me. Share this post Link to post Share on other sites
pwrguy Report post Posted November 26, 2017 I'm on the 5th and last firing of my Rem cases (300 WM). I noticed this last go around many of the primer pockets have become sloppy. Not one single failure so far on this batch of brass. Share this post Link to post Share on other sites
300RUM Report post Posted November 26, 2017 It's a reasonable assumption that case failure cause a flyer. Gas definitely vented through the action which means it didn't go down the barrel therefore MV was reduced. There would also be an inconsistency in how the barrel vibrated in relation to the rounds without a case failure. It's got flyer written all over it. 1 Share this post Link to post Share on other sites
