Ok, but practically it does make a difference.
As above I shot a few matches using a very average (.27 G1 BC) bullet and the difference between that and a "proper" cartridge was significant.
I know the 75BTHP is much better (still only .355 G1) than the 62SPBT but it's still an example of how it does all add up.
Add to that the higher BC bullets will retain more energy so should be easier to spot impacts/misses at range also.
I understand what you are saying in your posts, but from what I've seen overall wind drift is the most important figure not just the error margin the extra BC gives you. Most people I see at events will hold edge of plate regardless of the wind conditions, and many people aren't even trying to work out how the terrain will be effecting their bullet.
Add to that the wind being at a different angle than what you are seeing, or even worse a switchy tail/head wind then overall wind drift becomes important in practicse.
Using the same load above, shooting in changing winds, when it's raining at distance, trying to spot misses was near impossible, and even the hit's were very hard to see, and were often only heard.
I get that this is for his trainer so the 75BTHP are probably going to be the best bang for the buck training bullet regardless, but even on a flat range unless he is shooting at electronic F-class targets, the better bullets will pay off.
If he cant get anything other than the 75BTHP, 73ELD-M, 77SMK etc, class of bullet to shoot then of course he should just be happy enough shooting that class of bullet. But trying to squeeze every bit of performance is worth it IMO.
