Ive only ever had one 22/250 and thats an A I version. It started life as a mod 12 varmit in 223 i bought from a friend.
It was my intent from the getgo to have it rechambered to 22/250. The smith i used is an old friend in Emporium PA.
It only took a slight nudge from him to convine me on the A I chamber. He had sold his 22/250 and built a new gun on the 243 case.
So he gave me a couple hundred rounds of his ammo loaded with h380 and 55 gr bullets. They shot very well in my gun as for groups.
That said my opinion is the heavier bullets are better suited to the cartridge. In about 1950 my father bought a model 70 win in 220 swift.
He always used 50 gr bullets and i believe 55 was about the largest available in the 50s. I dont recall us ever killing a groundhog beyond
about 400 yds with that gun. Main reason was we couldnt hit them. A few years later my brother in law bought a 22/250 rem. and he could
kill them just as far with that. Ive killed prairie dogs out to 600 or so using 69 gr smks in the A I 22/250. Beyond that i'll use a 105 gr in the 6x284.