Hey, way to go dude. I'm proud of ya.
1.25" groups are minute of Whitetail. I prefer sight ins at 200 yds, but I'm weird. I don't ever remember Jack O'Connor reporting a half inch hunting load. If they were inchers he went hunting.
What cartridge are you loading for?
The proper way to measure group size is to measure the outside of the two widest shots and then subtract one bullet diameter.
Example: rifle is 308 Win. Three shot group at widest point is 1.50 inches. Group is 1.500 - .308 = 1.192 ".
Your question "how will a load perform at different yardages", and my best ewag, educated wild a$$ guess, I don't know and neither can anyone else answer that. It may and it may not.
Something about MOA. Moa @ 100yds is 1". At 200yds it's 2', at 300 it's 3" and so forth as far as you can shoot.
Remember were open 24 hours a day at the "Church of the Lost Cause" to solve all reloading, shooting and marital problems. In business circles we are also known as The Grace L. Ferguson Storm Door and Airline Company.
I gotta quit drinking beer while I'm posting.
Best wishes, Bill