borderlands

Weapon proficiency is a passive attribute in Borderlands that a character can build for each weapon type. Characters gain proficiency for the equipped weapon whenever experience is gained from a kill. This applies even if the kill is scored by an allied unit, including a team mate, a Bloodwing or a Scorpio Turret. Kills scored from standard melee attacks and grenades also count towards the class of the weapon currently wielded.

Bonuses

Each proficiency level gives you three bonuses for every weapon in that category, which affect different weapon characteristics:

Damage - Adds to the weapon's 'Manufactured Damage'.
Reload Speed - Decreases the time it takes to swap out a weapon's magazines.
Accuracy - Improves the character's handling of the weapon. See Accuracy.
Stability - Exclusive to Sniper Rifles, Stability decreases the time it takes for a rifle to 'settle' after lining up the scope, after firing a shot and after taking damage.[1][2]
Cooldown Rate - Exclusive to Eridian Weapons, Cooldown reduces the time it takes an Eridian weapon to recharge.
Rate of Fire - Increases the rate at which a weapon can fire one shot after another. While not exclusive to any one weapon type, Shotguns and Sniper Rifles earn a rate-of-fire bonus for proficiency.

Level Experience Bonus #1 Bonus #2 Bonus #3
Required
to level up
Total Damage Reload Speed
Rate of Fire
Cooldown Rate
Accuracy Stability Rate of Fire
1 2,400 2,400 - +6% - - -
2 4,800 7,200 - +6% +9% +12% +6%
3 7,200 14,400 +3% +6% +9% +12% +6%
4 9,600 24,000 +3% +12% +9% +12% +6%
5 12,000 36,000 +3% +12% +18% +24% +12%
6 14,400 50,400 +6% +12% +18% +24% +12%
7 16,800 67,200 +6% +18% +18% +24% +12%
8 19,200 86,400 +6% +18% +27% +36% +18%
9 21,600 108,000 +9% +18% +27% +36% +18%
10 24,000 132,000 +9% +24% +27% +36% +18%
11 26,400 158,400 +9% +24% +36% +48% +24%
12 28,800 187,200 +12% +24% +36% +48% +24%
13 31,200 218,400 +12% +30% +36% +48% +24%
14 33,600 252,000 +12% +30% +45% +60% +30%
15 36,000 288,000 +15% +30% +45% +60% +30%
16 38,400 326,400 +15% +36% +45% +60% +30%
17 40,800 367,200 +15% +36% +54% +72% +36%
18 43,200 410,400 +18% +36% +54% +72% +36%
19 45,600 456,000 +18% +42% +54% +72% +36%
20 48,000 504,000 +18% +42% +63% +84% +42%
21 50,400 554,400 +21% +42% +63% +84% +42%
22 52,800 607,200 +21% +48% +63% +84% +42%
23 55,200 662,400 +21% +48% +72% +96% +48%
24 57,600 720,000 +24% +48% +72% +96% +48%
25 60,000 780,000 +24% +54% +72% +96% +48%
Level Experience Bonus #1 Bonus #2 Bonus #3
Required
to level up
Total Damage Reload Speed
Rate of Fire
Cooldown Rate
Accuracy Stability Rate of Fire
26 62,400 842,400 +24% +54% +81% +108% +54%
27 64,800 907,200 +27% +54% +81% +108% +54%
28 67,200 974,400 +27% +60% +81% +108% +54%
29 69,600 1,044,000 +27% +60% +90% +120% +60%
30 72,000 1,116,000 +30% +60% +90% +120% +60%
31 74,400 1,190,400 +30% +66% +90% +120% +60%
32 76,800 1,267,200 +30% +66% +99% +132% +66%
33 79,200 1,346,400 +33% +66% +99% +132% +66%
34 81,600 1,428,000 +33% +72% +99% +132% +66%
35 84,000 1,512,000 +33% +72% +108% +144% +72%
36 86,400 1,598,400 +36% +72% +108% +144% +72%
37 88,800 1,687,200 +36% +78% +108% +144% +72%
38 91,200 1,778,400 +36% +78% +117% +156% +78%
39 93,600 1,872,000 +39% +78% +117% +156% +78%
40 96,000 1,968,000 +39% +84% +117% +156% +78%
41 98,400 2,066,400 +39% +84% +126% +168% +84%
42 100,800 2,167,200 +42% +84% +126% +168% +84%
43 103,200 2,270,400 +42% +90% +126% +168% +84%
44 105,600 2,376,000 +42% +90% +135% +180% +90%
45 108,000 2,484,000 +45% +90% +135% +180% +90%
46 110,400 2,594,400 +45% +96% +135% +180% +90%
47 112,800 2,707,200 +45% +96% +144% +192% +96%
48 115,200 2,822,400 +48% +96% +144% +192% +96%
49 117,600 2,940,000 +48% +102% +144% +192% +96%
50 120,000 3,060,000 +48% +102% +153% +204% +102%
k 2400*k 1200*(k^2+k) floor(k/3)/100*3 ceil(k/3)/100*6 ceil((k-1)/3)/100*9 ceil((k-1)/3)/100*12 ceil((k-1)/3)/100*6

Notes