I've tried numerous loads in my Windham Weaponry Varmint exterminator barrel with 55 grain V-Max and 68 Grain HPBT. This gun does not like them pushed fast. Right now the load is 23 grains H322 for both bullets. Both shoot one hole at that level.

I don't know, maybe the 1-8 twist is not good for the 55, who knows? Maybe it's something I'll never know. The barrel just doesn't like a faster load.

So I looked up the drop on the load at 3100 fps and 3300 fps. The drop is 1.8 inches more for the 3100fps than for the 3300fps at 300 yards. If that would cause a miss, given it's a known value, then that's not really the cause. My shooting would be the cause. And the 3100fps load will kill a woodchuck or coyote just as fast as the 3300fps load.

A consistent known is the thing here, heck, I've killed bunches at 300 and much farther with a 222 in the past.

It's weird, it works, run with it. I would have never figured on H322 as the load, I tried it on a whim.

I load 62 Barnes to the max in my Rock River varmint. You might try those. Damn near one hole shooter. Varget powder. I have some CFE, but haven't tried it yet.

With hornady it depended, bullet to bullet... 75 bthp you could not push hard no matter what I tried... 75 amax you could hammer... go figure.

I've never really been a fan of H anyway.

To start, using 33 or 34 g. W760 and mag primer. This AM at 100 yds., with a 12' twist 22/250, three Berger 60 g. were touching.
But the 69 g. (Nosler) was all over the place and another 69 g. was off the paper except for the one that went in sideways. Experimenting with a trusty old rifle that has been great with 45g. to 55 g. forever, but never shot anything heavier/longer. Most realize that ROT can matter a lot, and clearly with this old Douglas there is a decided breaking point.

I use a lot of H-322 in various chamberings.

It does some good groups.

Actually the only reason I have H322 on hand is that I use it in my 45-70.

I'm curious how your rifle shoots with other bullet weights? I only ask because I have the same rifle and found it to shoot best with bullets lighter than 55. 50-53 seem to shoot best in mine and it's never shot as well with 55 and heavier.

I haven't tried them. I do have some 50 grain Noslers I could try.

I shot 20 rounds into a single 3/4" hole today. 5 at a time as fast as I could load the mag.