.223 Remington (5.56x45mm)
With the purchase of my CZ 527, and the rapidly approaching coyote season, the focus of my handloading has shifted back to a predator load. I have gone to factory ammunition for personal defense purposes.
Hodgdon VARGET is the obvious best choice for .223 Remington, because it yields faster velocity, is a Hodgdon Extreme powder (which makes it relatively insensitive to temperature variations), and is a compressed charge in most loads. However, IMR had introduced a new powder, 8208 XBR, which also yields high velocities and is advertised as being totally insensitive to temperature changes. There is also H4895.
Eventually, I will want to go back to making predator loads that are accurate in my AR-15, because I can easily mount a night vision scope to it.
This varmint ammunition will be used primarily on coyote, but also occasionally groundhogs. This will be the load I use with my CZ 527. The bullet should be in the neighborhood of 55gr, because I want plenty of energy out to 400 yards, and because the rifle's rate of twist and the scope's reticle are both optimized for 55gr loads.
I have a bunch of BlitzKings, but I should also try the 53gr Hornady V-Max and probably the Nosler 55gr Ballistic Tip. I want a varmint bullet with a high ballistic coefficient in this weight range, which basically means a boat tail and a polymer tip.
There are three powders I definitely want to try: VARGET, H4895, and IMR 8208 XBR. If none of those work out, there are at least three other Hodgdon Extreme powders I can try.