Sounds like you dodged a bullet(no pun intended as this is a serious topic) big time. It sounds like the ammo is not 9x19, otherwise know as 9mm Luger, 9mm parabellum(sp?). Like George says, mic the case and the bullet for dimension, I suspect the OAL (overall length) of the case is shorter than 19mm, allowing the case to slip foreward in the chamber. 9mmLuger headspaces on the case mouth, the stuff you have sounds like it is too short for the chamber. The keyhole effect is a mixed blessing. Fortunatly, it sounds like the slug is undersized for the .355 bore, and is not engaging the rifleing. That is a good thing because it kept the pressures down. Also a good thing is that you were using a Ruger(the things are dump truck tough), a lesser gun may have come apart in your hands. There are more 9mm designations out there than you can shake a stick at, so it pays to be sure of what you are buying. I would ask 2 or 3 or 10 people what exactly the cartridge was if I was unsure and it wasn't marked clearly, the price was so good you can't pass it up, or even if it was some stuff that somebody loaded at home. If they think I'm being a jerk for asking so much, screw em, it ain't their eyes, hands or fingers that are going to go if it doesn't work. I'm just guessing, but it sounds like somebody had a load of oddball stuff that they wanted to unload. Next show, I would have a serious discussion with the seller about what he is selling, and how it was advertised.
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