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