first screw velocities when your talking about air rifles. The .177 is the least effective air rifle caliber for hunting. The .22 is generally the best caliber for all around hunting. It is an entire millimeter ( 4.5-5.5 mm )bigger and the pellets are almost twice as heavy. To hunt coyote with an airgun use a big bore air rifle. Use the .357 caliber, the .45 or .50 shoot too slow ( were talking about trajectory now ) for a long range shot. ( Keep in mind these big bores can be as loud if not louder than a .22 lr )The .357 Sam Yang Recluse is good. I would try to find someone to give it a super "tune" ( increase power, polish insides, etc. ) to increase the energy from 150 ft.lbs to about 200+ ft.lbs, look for Big Bore Bob he might be able to do it. For a gun out of the box ready use a Benjamin Rouge. It is twice the money, but worth it. It has an LCD display for you to customize the power and fill pressure for your bullet weight. It produces around 190 ft.lbs ( Crosman, who owns Benjamin, exaggerate the velocity of the guns they use lightweight and inaccurate pellets to test for velocity because "speed sells" ) and bullets custom made for it by Nosler. It is also a 6 shot repeater bolt action rifle. The Recluse is a single shot rifle. The Rouge is also much quieter with the Shrouded barrel. If you want a .25 caliber air rifle the Benjamin Marauder is also good. Just adjust the velocity screw to max and adjust the hammer and you have 60+ ft.lbs with 43 grain pellets. By the way these are all PCP/Pre Charged Pneumatic Air Rifles. Which means you need a High Preassue Air pump or a Scuba Tank to fill the gun up or "charge" the rifle.