Arguably the best post WWII article on Snapshooting was written by Francis Sell for a 1959 issue of Guns Magazine. The article: Snapshooting and Snapshooting Rifles defines Snapshooting well, giving sound advice.
The key descriptions are on the right side. This article must have frustrated Francis Sell as the word trigger is inadvertently used where the word hammer should have been used. I would imagine every writer has an article like this.
If MD were not such a slacker and got himself all retired that way he could have written a modern interpretation of Snapshooting and we could have chewed on it for awhile.
[Linked Image from i.imgur.com]

Slim