J996 - Thanks for your response.
The other issue I was trying to avoid was the necessity of a rangefinder to setup at a closer distance. 84 feet between 300m and 300yd is over 3 tape lengths if I take a standard measuring tape and the range is already covered in snow. The intent of listed group sizes seems to be MOA, 2/3MOA and 1/3MOA - if that sounds funny, you could just use MOA, 1/2 and 1/4. I would suggest changing the thread title if MOA measurements are not going to be used (3" 10rds @ 300yards Challenge).
Maybe metric shooters could scale down their group sizes mathematically to 300yards? You could ask posters to report their result in MOA - many have already done so anyway.
Food for thought - thanks for your consideration.
1moa is 1.05 inch right.
So if that's the deal then people just need to switch the max from 3 inches to 3.15 max.
Or am I missing something.