Primer Pocket Blowout — Another Reason to Wear Eye Protection

Our friend Grant Guess experienced a “close call” with a defective primer a few years ago. A defective primer caused a part of the casehead of one of Grant Guess’s rounds to blow out. This allowed high-pressure gas to escape through the damaged primer pockets. Look closely, boys and girls. It is another good reason to always wear safety glasses when you shoot. The cartridge was a Winchester-headstamp necked-down.270 Win brass. Grant reports, “I had a blast-through today between the primer and primer pocket. The action was really smoking, and I got gas in my face. This was a relatively light charge. Thank God for safety sunglasses. I should also mention there appears to be a 3/64-inch hole halfway between the primer pocket and the primer. It was like a small hole burned through both of them. It could happen to you. One of Grant’s Facebook Friends, Chris D., commented: “Search the Internet, you will find a lot of pinhole failures in the corners.” Winchester has a problem with the LR primers.Grant examined the damaged case after the incident: “I [measured] and the flash hole is not too large or too small. The primer has a clear area of defect. It doesn’t take a lot of a defect at [50,000 CUP] to cause problems. The next shot had a little pucker factor ….”