First off, who knows what powder Federal use in their Classic hi shok ammo in .22/250? I'll explain later why I ask.

I've been working up loads using H380 to push 55 grain V-Max bullets through my heavy barrelled Tikka and am down to testing 4 loads (36.4, 36.9, 38.4 & 38.9) at 200 and 300 metres having had good results at 100 metres, in all cases excellent with overlaps and half inch groups. I volume measure and weigh my loads and shoot them in groups of 3.

Today @ 200 metres, POI was the same or higher than last time out, even though fps @ 12 feet from muzzle was lower today by 0.5% to 1.7%. Same ground, significantly lower air temperature today AND today I was storing my ammo in an open box in the shade until needed, so why might that have been so?

My best group today was with 38.4 gr at 0.5 inches. Next time out, I'll test the same loads @ 300 metres and then make a choice.

Now, here's the rub. Just for fun, I shot a group of Federal factory ammo last of all and guess what? This group was just tighter than the 38.4gr load and POI was lower by 2 inches, bisecting the vertical difference between POA and POI. Kinda makes you wonder why you bother sometimes, doesn't it?

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Don't have any idea what Federal uses.

I haven't had all that great of luck with H380 in the 22-250. Best powder for me has been 4895. It is a bit of a pain though because you have to weigh it. That being said -- your .5" at 200 ain't nothin' to snear at.

As for POI remaining the same at different velocity -- sounds like your only talking about 20 to 60 fps difference. I doubt that would make much difference in POI at 200 meters

I have agree with Mike on the H4895. I use 35.5 gr with the 55gr V-Max. Air temp and density may have a say in POI. Also if rounds are kept in sunny vs. shaded areas the round could build up internal pressure due to heat from the sun. This is another advantage of H4895. It doesn't seem as temp sensitive as 380.