ORIGINAL: Prairie Wolf

Has anybody else had factory ammo that showed pressure signs?

I have on two occasions. Once was with winchester white box .22-250. I was getting 4300 fps (I think) on the chrony. It was 200 fps higher than the velocity listed on the box. After about a half dozen rounds I blew a primer and I haven't shoot a round of it since. The brass was flowing into the extractor groove, almost all the case heads were shiny from opening the bolt. In hindsight, it was stupid to keep shooting but I could not believe the factory would load them too hot. I still have the rest of the ammo.

The second occasion was just a few weeks ago. I ordered some Federal Premium 7mm WSM from midway on closeout with the 150 nosler solid base. My primary reason for buying it was to try out the federal cases for reloading, as I read the win cases were softer. I also figured if they shot accurately I would have good ammo to use this season. First shot blew the primer. I could barely get the bolt open. I didn't shoot any more.

I think in both cases, it was likely due to shooting when it was too hot out. It was summer both times. With the 7mm it was in the 90's, don't remember on the .22-250, it probably was just as hot. I am sure they loaded the rounds with ball powder and it was just too hot. I have the 7mm rounds in the freezer, when I get a chance I'll try another round to see if it makes a difference.

In the case of the .22-250, I am surprised that they loaded them so hot. That is a round that could be used in the summer on prairie dogs. The 7mm, that is a big game round and in most cases it would be a lot cooler than 90 degrees when you use it.

Has anybody else had something similar happen?