I use a target (vitals) size of 4" to determine MPBR on all my varmint rifles. That's 2" above line of sight and 2" below. So the rifles are zeroed such that the bullet does not rise more than 2" above line of sight (wich usually happens pretty close to 150 yards). Wherever the bullet then drops to 2" below line of sight is then considered the "MPBR" (maximum point blank range).
Using the rifle I use the most for coyote hunting as an example (a .17 caliber wildcat), the MPBR is 325 yards. So it is zeroed to be 1.6" high at 100 yards, dead on at 280 yards and 2" low at 325 yards. I use the same point of aim for every shot, from as close as I can get them, out to 300+ yards. The rifle I use next most on coyotes (a .20 caliber wildcat) is even flatter than that. Works for me. Note, though, that not many rifles shoot that flat. Certainly not anything like a .223.
Knock'em, there is no doubt that those Eastern coyotes are on average larger than their Western cousins. I think you might be surprised at how many coyotes at around 40 lb's I do kill, though. I skin probably 10 coyotes every year over 37 pounds, and at least one or two every year that go an honest 40 or more. The largest I've personally killed was a 44 pounder, but I've skinned several that were larger, one my partner killed (with my .17 Mach IV) was only a pound shy of 50, at 49 pounds. Most of these have been killed in Utah.
Two seasons ago, I measured the side profile chest depth of as many coyotes as I could. I was bouncing around an idea in my head for a custom scope reticle that would employ a super fast subtension ranging/aiming system for coyotes. So I needed to know the actual size (depth) of a coyotes chest. I was interested in the "visual" depth, as in what you see through the scope - hair and all. I'd have to dig up all the notes I took to give really accurate numbers, but I do remember that only the very biggest coyotes I measured that year (40 pounders) went 12" deep. But again, that was from the tips of the guard hairs to the tips of the belly hairs. I didn't measure them after skinning. But I don't think even the ones that went 40 pounds were more than 8" deep in the chest with the hair off? I think the average was probably closer to 6" deep. I could be wrong about that, obviously, since I didn't actually measure them skinned. But, I did measure and weigh a bunch of them before skinning. I'd have to say my best guess, is that even your biggest 50 pounders, probably don't go more than 9" deep? Just rambling here I suppose, no real point I'm trying to make, other than I suspect I might have a better handle on how big your coyotes are, than you think I do?
- DAA
