the strongest gun

[Hrith]

kinda hard to reply =/
do you mean "handguns" or anything a Ranger can weild ?
note that 'best-looking' is very subjective

most powerful rifle is Yasminkov 3000R
most useful rifle is Frozen Shooter
best looking rifle is Anti Android Rifle

most powerful handgun is S-Rank Gun
most useful handgun is S-Rank Gun
best looking handgun is Yasminkov 2000H

most powerful mechgun is Guld Milla
most useful mechgun is Guld Milla
best looking mechgun is Guld Milla

most powerful shot is S-Rank Shot
most useful shot is S-Rank Shot
best looking shot is Power Maser (but it COMPLETELY sucks)

most powerful launcher is Red Scorpio
most useful launcher is Red Scorpio
best looking launcher is Red Scorpio

most powerful bazooka is NUG2000-Bazooka
most useful bazooka is NUG2000-Bazooka/Iron Faust
best looking bazooka is NUG2000-Bazooka/Iron Faust

Spread Needle -- or S-Rank Needle -- is very unique and a ranger must-have.

best gear you can have is Frozen Shooter, Spread Needle, Guld Milla, but if you are legit, replace Guld Milla with Red Mechgun or Yasminkov 9000M.