the best 17 hmr or mach 2 , under 300 , is by marlin, period. and the 17hmr can take most varmints out to 200 yds, and will take out coyotes, out to 150. This is all stated with personal knowledge, and experience. However I don't recommend a 150 yard shot on a coyote. I have bought/shot all 17hmr's and mach 2's that are made, from about 300 bucks and under, and have kept these;
Rossi, kids model nickel washed s.s., 17hmr. 100 bucks.(found out an ammo it
likes , plus it likes it's front take down screw completely loose, go figure!!)
Anschutz 6417hmr pistol, 5 shot, with 12 inch bbl, 300 bucks from CDNN,
Trigger is better than sex, plus it is Anschutz, it shoots everything into 1 hole.
Marlin 917m2 , stainless laminate. Almost as good as the hmr, plus ammo is 2.5 times cheaper, so I am able to plink.
Marlin 717m2, the only cheap and reliable semiauto 17m2 made, shoots into a dime at 100 yds, plus under 200 bucks. Cant be beat. Thompson /Center makes a better one, but it is about 400 bucks.
now remmy makes a 17hmr semiauto, but you may need to tweek it, plus get the latest generation mags, so it will work well. Also there is now 20 or 25 round mags for the Remmy, plus after market internal parts now, like the ruger 10.22. but it aint cheap, their regular models are about 400 bucks, and their s.s. laminate versions are about 500.