Was hunting from a pop up blind with shoot through screens, seated with a good solid front rest. Breath, sight picture, squeeze... She twitched at the shot, and a half second later spun around and ran off the way she came, across the field and into the wood line. Given the circumstances I was positive I had made a good hit, but in the fading light and through the screens, it wasn't possible to see the impact (non-illuminated) to know for sure.
I sat for 15 minutes, then quietly backed out of the area and made my way to the house. An hour and half and a nice warm supper with the family later, I went back out to start tracking... and found... nothing. I grid searched the impact area and the route she ran for over a hundred yards and never found a spec of hide nor hair nor shaft.
Totally dejected - I went back to the house and started to dry the xbow off since there had been a slight drizzle, wondering how I could have missed - or if I had somehow made a horrible shot that left no trail. "tick tick" said the xbow as I ran the rag over the scope. "tick tick"?!? After the third or fourth time, that slight noise got my attention and that's when I discovered the scope mount base was loose - and not a little! The scope base assembly could pivot up and down considerably, easily 1/4" or better front to back.
This is my second season now with this Matrix 355, and I had replaced the string and snugged all the bolts maybe a month ago in preparation for this season - none were noticeably loose then, but each got a turn with torque wrench to be sure. I have zero idea how, when or why the base worked loose. I haven't been target shooting with it since before the season started after reconfirming zero, but after each hunt I have been shooting into a block to de-cock with a practice broadhead. The night before, when I shot to unload I did notice it was 2" high at 20 yards, but I just assumed I had rushed the shot... off-hand, nearly dark and not actually trying to aim all that much. In hindsight I'm guessing that is when the sight started to manifest some play.
Argh! Snugged everything back up today and re-zeroed. Was hitting 8" low at 20 yards initially. So that tells me the scope had at least 10" inches of vertical play @ 20 yards - likely more - which would have been even more exaggerated at the 35 yards I shot the night before. So, while I am confused as to how it happened, and frustrated with myself for not catching it before pulling the trigger, I feel better knowing that in all probability my shot sailed over or under my doe.
Long story short: check those fasteners - again.
Off to check the wife's purse for allen wrenches! She says she wants the freezer stocked but I know she is awfully fond of her "woodland creatures"!