Here is the full list of all 20 Reload achievements.
Shoot 100 pumpkins.
PLATINUM medal achieved in each rifle drill.
PLATINUM medal achieved in each sniper drill.
PLATINUM medal achieved in each military drill.
Get 5 SUPER TARGET BLAST bonuses.
PLATINUM medal achieved in each shotgun drill.
Play 10 shoot house levels in a row without hitting any civilian targets.
Shoot 100 cans, canisters and bottles.
Shoot 400 bad guy targets in M988 Troop Carrier levels.
Play all shoot house levels with no civilians shot and all bad guys eliminated.
PLATINUM medal achieved in each pistol drill.
Shoot 100 METAL targets.
Shoot 50 long range targets.
Get 20 TARGET BLAST bonuses.
Play all skeet shooting levels.
Get 20 Headshooter bonuses.
Shoot 200 WOODEN targets.
Shoot 100 bad guy targets in a row without hitting any civilians.
Shoot 200 PAPER targets.
Get 20 Quickshooter bonuses.