I have pretty much quit using Winchester primers.

by Catoosa, Tuesday, May 17, 2016, 09:53 (3119 days ago) @ Jared

This is a shame, as Winchester primers are one of the most easily obtained brands around here. I've got a bunch of them, but have not had any problems. Gonna check the lot numbers on the ones I have squirreled away.

Years ago I had the exact same problems with a particular lot of Remington LR primers. I had just started reloading (for a 6.5 Arisaka, coincidentally) and I was blaming myself for doing something wrong but had no idea what. Fortunately I saw an announcement in a magazine (WAY before Al Gore invented the internet)concerning the piercing problem with Remington primers. I contacted Remington and they sent me a whole carton to replace the 200 primers I had purchased. No problems since, and I think I'm still using primers out of that carton.