If it's a whitetail or similar, and not an elk or something bigger, You can use one of the self drilling, screw type drywall anchors, they come in both metal or plastic. The base screws into the drywall, then the screw goes into the base, leave the screw out 1/2 inch and you're good to go. they come rated for 65 - 80 lbs, depending on size in 1/2" drywall
Sorry guys. It is an elk. I use the anchors above for whitetail but I have one slot of wall space right now for an elk and it's fairly heavy with no studs. Sorry for the confusion but appreciate the help
I had a big whitetail mount I couldn't get to hang right even with the above anchors. Ended up cutting a hole in the wall alittle smaller than the mount and screwing a cross brace between the studs. Not the best idea but it worked and you can't see it
I think I'd go with a brace between studs. Depending on your mount it could be a surface mounted brace or the better way would be to cut out some drywall insert brace in wall between studs and patch drywall.
I would either try these toggler bolts as I know they use them in commercial construction a lot or these "wingits". They say they're rated for 300 pounds. I imagine if they can hold 300 the Hilti brand hangers should as well.
I would not hang an elk unless it was into a stud. My buddys elk fell of the wall after his young son bounced a ball off of it and gored him pretty good. His son was lucky, but the elk was not. wife made him get rid of it.
Go with the 1 x 4 across the studs. Cut to length, paint it if you want to match wall. Then you have a sturdy mounting pint directly attached to the wall framing. And - it is temporary as well. Move the elk, remove the board, patch four screw holes and your wall is pristine once again.
The 1 x will be less than $3. The screws and stuff are usually around the house, or if you just don't have them - ask someone at work. At least 2 inches, and 2-1/2 isn't to big.
The 1 x will be hidden behind the mount base.
Don't cut corners with something like this. Repairs are expensive, and might not be possible.
Do the job right the first time. In the grand scheme of things, a bit of time and effort now saves a ton of heartbreak later.