mine isnt Bushmaster, but i have a DPMS Varminter 223 it has 20in chrome molly bull barrel, 1-12 twist, its a flat top upper with a 4-16x44 scope, it cost me $800 i can drive tacks out to about 300 with it.

Just google "Bushmaster Varminter" and you will see lots of info. The DPMS Varminter is very similar and I would expect similar results... They are extremely accurate out of the box and I have never shot at running game with anything so deadly. Standing still coyotes or foxes out to 500 yards are just flat dead. With the very light recoil, your cross hairs stay right on the game. If you miss, you usually see the bullet hit in the scope and can instantly adjust your lead or holdover. You can effectively get off about 2 good, well aimed shots per second. The result is, you have time for 5-30 well aimed shots while the animal is still in range(depending on laws in your state). Once you get used to aiming the rifle and setting up the shot, you will find that you usually hit each coyote within one or two shots. If you have multiple targets, you get good shots on several of them. You will see a nice review by Gunblast at http://www.gunblast.com/Bushmaster_Varminter.htm

If you are hunting coyotes and foxes, you want the speed of the .223. Suggested retail is over $1300 but I got mine at a gun show from a private owner with scope mounts, Harris bipod and rubber receiver shim and magazines for $700. The cheap rubber shim at the back of the receiver really improves accuracy on the AR by locking up the wabble between the upper and lower units. I use a 6-25x scope with mildot reticle so I can be precise on lead and holdover out to 600 yards. I've plinked a few anteope with it and kind of quit using it because it is so deadly, it kind of dampens the sporting aspect of anelope hunting because they don't have a chance with a five round clip. I can put the cross hairs on a housefly at 100 yards and hit him right between the shoulder blades about 7 times out of 10 and the misses usually hit the wings or the head. I like the 24" barrel for speed and accuracy. Mine is a 1:9 twist but a 1:8 is even better if you want to shoot deer or targets at ranges over 500 yards because you can shoot up to 85g bullets. Kolbster's 1:12 twist will be excellent for varmints as long as 65g bullets are the largest you plan to shoot. Plan to reload for it and tune a load for the rifle. If you really want to eradicate varmints in your state, this is the tool. Good luck!