ORIGINAL: wallhangr
I noticed a similar issue with some mechanicals I had. While practicing with them on an inch and 1/2 thick foam target they were not opening but nearly passing completely thru. On deer however I got pass-thrus with the blades opening. I'm guessing you hit the yote where there wasn't much resistance and they didn't open.
Put a piece of paper directly behind your foam target, and you'll find that the bladesARE actually opening then closing. It doesn't make sense but you'll see it's the case.
Oh, by the way, every deer I've ever shot(CB) using Spitfires (blades ALWAYS opened) the blades were closed when I retrieved the bolt. Strange isn't it?
