Got an interesting feeling in my stomach this weekend, story:
Bought a rifle 5 years ago used at Gander Mt., Rem 700 Mountain chambered in .280 Remington, the thing was mint, rifling looked clean, very little wear on the bolt, wood was good. Finally got around to shooting it for the first time this weekend, so I had cleaned it good last week to kinda do a once over on it. Rounds fit in the chamber like they should. Yesterday I'm out at my shooting grounds in the U.P., take a shot (everything worked) and eject the round. I look at it and I think to myself that the spent casing doesn't look right. Here's the funny feeling part, because I was wondering whats the chance it could blow up because case stretch is normally not good.
Unfired on the left, fired on the right.
Decided to put that rifle away and research later upon getting back to the house. I had been aware of the .280 Ackley Improved, and knew of the cross compatibility but was not expecting to see this, cartridge and once I started researching it, it looks like that's what we have here. A chamber reamer is all that would be needed to open up the shoulder in the chamber as Ackley Improved's are based on a parent cartridge (.280 Rem in this case). But doing some reading I realized that part of P.O. Ackley's theory was that parent cartridges could be fired in his "Improved" chambers. (I won't get into why a steeper shoulder angle is a good thing here) While you would think that the stretch involved here wouldn't be good its actually one way of creating Ackley brass and its called fire forming. For bad case stretch google "glock kaboom", hence the funny feeling.
Moral of the story is, always, always! be cautious of used firearms, and on a new to you firearm, check your brass and make sure it looks good/right. Turns out in this case its alright, but who knows what could happen in another case hence the funny feeling.
Barrel stamp read ".280 Rem" so this rifle has had work done obviously
