Someone Explain Achievements Please?

[Hammy]

I cant seem to figure out when a character would get an upgraded weapon.
I mean, I get killed by them all the time, so I am left wondering where I can see the information.

[H0ly-H@nd-Gr3nade]

If you go here you can see all the achievements in the game (these are just the basic ones that came out with the game).

From there, you can click to see all the medic ones, or pyro ones (with the link in the appropriate section). When you go to one of those classes pages, at the bottom there are achievements named Milestone 1, etc. When you complete each milestone, you get a new weapon.

[CarbonFire]

If you look at the bottom of each achievement list, you'll see three milestones.

I believe they are at 10, 15 and 20.

At 10 achievements
Medic: The Blutsaugher - Leech 3 health with each needle hit on an enemy, 0% Crit Chance
Pyro: Flare Gun - Long range weapon lights people on fire (does more damage the farther it flies), no damage to buildings

At 15 achievements
Medic: Kriztkrieg Medigun - 100% Crit chance + 10% charge speed bonus - replaces Uber
Pyro: Backburner - 50 Extra Health and 100% Crit chance when burning people from behind, no Leafblower

At 20 achievements
Medic: Ubersaw - Each hit adds 25% charge to Medigun (Uber or Kritz), 20% Slower rate of fire
Pyro: Axtinguisher - 100% Crit chance when used on ignited foes, half damage and 0% Crit Chance against non-ignited foes

[H0ly-H@nd-Gr3nade]

For the Medic it is 10, 16, 22.
For the Pyro it is 10, 15, 20.