Counterstrike Global Offensive Danger Zone: How many bullets to kill a drone?

So I set up a server in CS:GO using these commands:

game_mode 0
game_type 6
map dz_blacksite (I used blacksite as the test map)
sv_cheats 1

I used this command to spawn drones:

ent_create drone

And this command to drop weapons:

give weapon_"weaponname"

Using these commands I found the minimum number of bullets it took for each weapon to shoot down a drone.

Pistols

• Took 3 bullets: USP-silenced and unsilenced, P2000, Glock, Dual Beretta, Five Seven, Tec-9, CZ-75
• Took 2 bullets: p250, Deagle
• Took 1 bullet: Revolver

SMGs

• Took 4 bullets: Bizon
• Took 3 bullets: MAC-10, MP7, MP9, P90, UMP45, MP5

Heavy Weapons

• Took 3 bullets: M249, Negev
• Took 1 pellet: MAG-7, Nova, Sawed-Off, XM1014

Rifles

• Took 3 bullets: M4A1-Silenced and unsilenced, M4A4, AUG, SG553, Galil, Famas
• Took 2 bullets: AK47
• Took 1 bullet: G3SG1, SCAR-20, SSG-08, AWP

Some interesting observations:

• Distance was not a factor for bullets needed
• If the drone bounced off a ceiling of some sort before you shot your 1st bullet, it reduced the required bullets by 1 for all weapons (except for the weapons that are 1 hit of course)
• Being in the red Danger Zone does not affect the drone or the amount of bullets taken

Hope this helps.