Congrats on your successful hunt. Somebody chimed in with a figure of 60% of live weight - I think that sounds about right. I shot one down around Medford several years ago, and it was the biggest blacktail I have ever seen. The carcass weighed 117# on a meat processor's scale in Canby. He told me 225 on the hoof, but my past experience with dozens of large-bodied Minnesota whitetails put my guess at an even 200. ( I had seen the whole animal, and I was the guy who put it in the back of the pick-up. It looked & felt like a 200-pounder to me.) Anyway, my guess for you is somewhere around a hundred and a quarter.
Those Oregon blacktails are some of the best tasting venison I've had anywhere - better even than farm-fed whitetails. I wish that it was cold enough here in deer season to let a carcass hang for a couple of weeks before having to cut it up. That makes a whale of a difference in how they taste.
I'm leaving Friday to go chase them around in an area on the east slope of Mount Hood. That area has a lot of bench-leg deer, since it's right on the edge of the mule deer range. We may get into some big animals.