Re: 75gr Hornady BTHP for coyotes???
I shoot the Hornady 75 BTHP out of a CZ 527 Kevlar Varmint in .223 Rem.
I recently worked up some new loads and chronographed them.
Both loads will hold 1/2" groups at 100 yards. Both loads at set at 2.250" COL, and that just puts them on my lands.
25.0 grains of Varget. 2848 FPS with 1351 FPE.
24.5 grains of H4895. 2874 FPS with 1376 FPE.
Those speeds and energies are not excessive, and are at the max in the Lee Load Manual. The 5.56 SS109 NATO FNM 92-3 that I shoot is 3179 FPS with 1392 FPE and that is a hard 62 grain bullet. It is also a very good hunting bullet for blowing through tough bone per a guy in Montana who hunts deer with it. Mine is all new production that I have stored carefully since 1993. I bought a lifetime supply when it was 37 cents a rounds brand new, all hermetically sealed and boxer primed. Very good FN brass. The chronographed extreme spread is 21, which is fabulous for mass produced military ammo. Accurate enough for 200 yard work, which is the guaranteed maximum yaw and snap range. The FN designed SS109 ammo was designed to yaw and snap into two tumbling halves at about 8" penetration in flesh, so it is a legitimate hunting bullet in deer sized game. My SS109 ammo was made by the company that designed it, so it is 100% effective, and I have done a ballistic test that proved the bullet yawed and broken in half as intended. This ammo can probably be made more accurate by pulling the bullets and taking out a bit of the powder, as the SS109 is loaded to a speed standard and not an accuracy standard. The standard is 3140 FPS out of a 20" barrel plus or minus 40 feet per second. I find that reducing the SS109 bullet 100-150 feet per second below NATO specs gives the best accuracy in my reloads. The American designation is M855, but they usually do not equal the European bullets in accuracy, especially Winchester M855 which is the worst American manufacturer. Lake City will beat it, if you can find it.
I had a previous 75 BTHP load, that was chosen to match my 75 grain Swift Scirocco load as a cheaper practice ammo. It is 23.4 grains of IMR 4895 at 2766 FPS and 1274 FPE. Have not chronographed the Swift Scirocco load yet, but this 75 BTHP load was set for the same zero point at 200 yards, and since it was meant for mule deer on the prairie, a 100 yard zero has little meaning for me. The 75 Swift Scirocco and the Hornady 75 BTHP have a very similar BC which is why I chose this combination. Though recommended for 8" twist, at 3000+ feet of altitude both stabilize very well in a 24" barrel with 9" twist if you keep speed above 2750 FPS. Since I have a very nice glass bedded CZ 550 in 7mm Mauser, it is doubtful I will shoot a mule deer with the 75 Scirocco. I would have no doubts it would work well on smaller whitetail deer out to 200 yards, but the mule deer I shoot run 200+ pounds and the shots are generally far in excess of 200 yards. Will not waste a deer tag on a whitetail as long as I have hunting rights on a private ranch full of mule deer. 250 pound mule deer and 150 pound whitetail have the same meat processor cost.