Yeah that's why there's a bunch of backs in the freezer. But with getting sick Nov 2020 I didn't feel up to making soup. ... and birds needed to be harvested and stuffed in the freezer. I can get a parted turkey in a gallon vac bag lol
I also have discolored ones in fall and winter. One suggestion is in off season some breeds shrink, atropine, until breeding season. Seems to be the case in mine.
https://www.backyardchickens.com/threads/discolored-testicle-in-heritage-mix-cause.1277956/
I put the curve over the back of the neck and blade on the front for chickens.
Older turkeys I had to go on the side and do both sides. It wouldn't go through the 4 yr old Tom's neck bones. It will go through jakes.
I use the PVC cutter
and a cut up kitty litter jug as a cone.
I tape the legs with cheap electric tape. They keep the head in the jug until I pull it out. Bird below has head tucked in jug.