This is a guide that was primarily created for the sole purpose of educating others on how I got the achievement, Artillery Barrage, in PAYDAY 2. I like to consider this the best, though time-consuming, way.
Other PAYDAY 2 Guides:
- Rifle Build.
- Shotgun Build.
- Critical Explosive Crossbow Build.
- Enter the Gungeon Achievements / Trophys.
Kill 25 enemies at 40 meters or more using only the GL40 grenade launcher. Unlocks the Wooden Stock for the Gecko 7.62 rifle, Pirate Barrel for the GL40 grenade launcher, Bone material and Muerte pattern.
Normal Bomb: Forest
First off, grab a cop hostage near clearly identifiable object, such as a tree, at least a few meters away from other trees, rocks, and so on.
Secondly, place a few Sentry Guns (set on AP, Armor Piercing rounds) near the hostage so that no cop tries to free your soon-to-be-exploded cop "buddy".
Next, obviously, move at least 40 meters away from the hostage, preferably on a train.
Next, aim your GL40 into position so that the grenade accurately fires from the barrel of the Grenade Launcher and within about 2 meters of the cop hostage down there, on the ground, at least 40 meters away from you.
Next, repeat until you get the achievement. Quite simple, really. Yeah, fo' sho.