Atmospheric conditions is your worst enemy. In hot conditions even the greatest of the scopes will magnify haze and mirage allowing you to see bullet holes at 300 yards on an intermittent basis.What's a reasonably priced spotting scope for "seeing" .22- & .30-cal holes at 300-yds - without having to use Shoot-n-See targets as spotting aids?
The one I have now, an old Redfield purchased in the late '80s, is only 'okay' to about 200-yds if the lighting conditions are just right. But I often shoot to 300-yds and further (M1 service rifle), so I'm looking to upgrade.
I have a Nikon Fieldscope 25x75x82 considered one of the top tier scopes and when temperatures reach above 90° I am not able to see a bullet at 300 yards. When temperatures are in the 70's and lower on a bright crisp sunny day I can see the bullet holes without the shoot NC targets.
Here is a link for an old article but with great information on spotting scopes and what is required for targets and seeing bullet holes at various distances. Even though the article is old and there are newer scopes the information still applies now.
https://www.opticsplanet.com/howto/how-to-choose-a-spotting-scope-for-target-shooting.html