Rise of the Ronin
51 Achievements
60-80h
Firearm Genius
Received the highest rank (Master) in firearms training.
41.1%
How to unlock the Firearm Genius achievement in Rise of the Ronin - Definitive Guide
Josh, Wise
This trophy isn’t too tough to unlock. First head to a firearms training point. There is one in Kanda, which you can see on the map here:
Talk to the man in there and activate the firearms training drill. Now, you will be charged with reaching a high score within a time limit. This challenge isn’t really very difficult. You have to hold 
to aim and pull 
to fire, and you have to aim at the targets. The way to gain high points is to shoot through wooden targets, because your bullets penetrate wood, and you can hit targets behind targets. The metal targets are worth more, but you can’t penetrate them. Once you have reached 7,000, you will achieve Master rank, and the 'Firearm Genius' will unlock.
You will also receive a Foreign Book, which you can give to Igasichi to increase your Bond.
Crazybasil
stratege.ru
stratege.ru
To achieve the "Master" rank in this competition, you need to hit at least 12 wooden and 15 metal targets within the time limit (hitting multiple targets at once will give you a higher score). The requirements for other tests will be different.
Some missions feature stationary machine guns or cannons. Don't try to break targets with it, first destroy all obstacles, only then switch to the main target. When you run out of ammo, you will exit the machine gun mode automatically: this is faster than leaving it manually. Cannons, where they exist, are a necessary tool for getting the highest score: follow the flight path of the cannonball, it must penetrate all wooden targets and hit the metal one, destroying all targets around the epicenter of the explosion and giving a huge number of bonus points.