Like any weapon, become proficient with a handgun takes a lot of practice. It's definitely makes it easier when you can put on a scope and rest it on something solid, again, like any other weapon. Don't assume that a pistol is inherently inaccurate. I'd dare to say that most decently built handguns are as accurate as rifles of similar build quality.
How's .589" at 100 yards with a 221 Fireball and tailored handloads?
1.28" at 100 while breaking in a 460 Encore with cheap factory fodder?
How about 5-shot sub-MOA accuracy with a 460 S&W revolver?