diff --git a/code/datums/ammo/shrapnel.dm b/code/datums/ammo/shrapnel.dm
index e27caa4b27..ac48a3f909 100644
--- a/code/datums/ammo/shrapnel.dm
+++ b/code/datums/ammo/shrapnel.dm
@@ -34,6 +34,31 @@
 	stamina_damage = 25
 	shrapnel_chance = 0
 
+/datum/ammo/bullet/shrapnel/canister
+	name = "low velocity canister shot"
+	icon_state = "buckshot"
+
+	accuracy_var_low = PROJECTILE_VARIANCE_TIER_6
+	accuracy_var_high = PROJECTILE_VARIANCE_TIER_8
+	accurate_range = 5
+	max_range = 8
+	damage = 25
+	penetration = 0
+	shell_speed = AMMO_SPEED_TIER_1
+	damage_armor_punch = 1
+	pen_armor_punch = 0
+
+/datum/ammo/bullet/shrapnel/canister/on_hit_mob(mob/M, obj/projectile/P)
+	knockback(M, P, 4)
+	slowdown(M, P)
+
+/datum/ammo/bullet/shrapnel/canister/set_bullet_traits()
+	. = ..()
+	LAZYADD(traits_to_give, list(
+		BULLET_TRAIT_ENTRY_ID("turfs", /datum/element/bullet_trait_damage_boost, 6, GLOB.damage_boost_turfs),
+		BULLET_TRAIT_ENTRY_ID("breaching", /datum/element/bullet_trait_damage_boost, 6, GLOB.damage_boost_breaching),
+		BULLET_TRAIT_ENTRY_ID("pylons", /datum/element/bullet_trait_damage_boost, 5, GLOB.damage_boost_pylons)
+	))
 
 /datum/ammo/bullet/shrapnel/hornet_rounds
 	name = ".22 hornet round"
diff --git a/code/game/objects/items/explosives/grenades/marines.dm b/code/game/objects/items/explosives/grenades/marines.dm
index 46d2d4eba9..14c5b143cd 100644
--- a/code/game/objects/items/explosives/grenades/marines.dm
+++ b/code/game/objects/items/explosives/grenades/marines.dm
@@ -130,6 +130,36 @@
 	shrapnel_count = 56
 	falloff_mode = EXPLOSION_FALLOFF_SHAPE_LINEAR
 
+ /*
++//================================================
++				Canister Grenades
++//================================================
++*/
+
+/obj/item/explosive/grenade/high_explosive/airburst/canister
+	name = "\improper M108 canister grenade"
+	desc = "30mm canister grenade, effectively low velocity buckshot. Substantial close combat impact when paired with the 5 round PN pump action grenade launcher. No, you can't set it off with a hammer, moron."
+	icon_state = "grenade"
+	item_state = "grenade_hedp"
+	hand_throwable = FALSE
+	underslug_launchable = TRUE
+	explosion_power = 0
+	explosion_falloff = 25
+	det_time = 0 //this should mean that it will explode instantly when fired and thus generate the shotshell effect.
+	shrapnel_count = 20
+	shrapnel_type = /datum/ammo/bullet/shrapnel/canister
+	dispersion_angle = 15 //hopefully this means the cone spread is pretty small
+/obj/item/explosive/grenade/high_explosive/airburst/canister/proc/canister_fire(mob/living/user, target)
+	var/direction = Get_Compass_Dir(user, target)
+	var/position = get_step(user, direction) //otherwise we buckshot ourselves
+	create_shrapnel(position, min(direct_hit_shrapnel, shrapnel_count), direction , dispersion_angle, shrapnel_type, cause_data, FALSE, 100)
+	if(shrapnel_count)
+		create_shrapnel(loc, shrapnel_count, direction, dispersion_angle, shrapnel_type, cause_data, FALSE, 0)
+	qdel(src)
+// canister has no impact explosion.
+/obj/item/explosive/grenade/high_explosive/airburst/canister/launch_impact(atom/hit_atom)
+	return
+
 /*
 //================================================
 				Airburst Grenades
diff --git a/code/modules/projectiles/gun_attachables.dm b/code/modules/projectiles/gun_attachables.dm
index 4f0daf2a2b..cbf7cb8c87 100644
--- a/code/modules/projectiles/gun_attachables.dm
+++ b/code/modules/projectiles/gun_attachables.dm
@@ -2800,13 +2800,18 @@ Defined in conflicts.dm of the #defines folder.
 	msg_admin_attack("[key_name_admin(user)] fired an underslung grenade launcher [ADMIN_JMP_USER(user)]")
 	log_game("[key_name_admin(user)] used an underslung grenade launcher.")
 
-	var/pass_flags = NO_FLAGS
-	pass_flags |= grenade_pass_flags
-	G.det_time = min(15, G.det_time)
-	G.throw_range = max_range
-	G.activate(user, FALSE)
-	G.forceMove(get_turf(gun))
-	G.throw_atom(target, max_range, SPEED_VERY_FAST, user, null, NORMAL_LAUNCH, pass_flags)
+// canister nades explode immediately and don't leave the barrel of the weapon.
+	if(istype(G, /obj/item/explosive/grenade/high_explosive/airburst/canister))
+		var/obj/item/explosive/grenade/high_explosive/airburst/canister/canister_round = G
+		canister_round.canister_fire(user, target)
+	else
+		var/pass_flags = NO_FLAGS
+		pass_flags |= grenade_pass_flags
+		G.det_time = min(15, G.det_time)
+		G.throw_range = max_range
+		G.activate(user, FALSE)
+		G.forceMove(get_turf(gun))
+		G.throw_atom(target, max_range, SPEED_VERY_FAST, user, null, NORMAL_LAUNCH, pass_flags)
 	current_rounds--
 	cocked = FALSE // we have fired so uncock the gun
 	loaded_grenades.Cut(1,2)
diff --git a/code/modules/projectiles/guns/specialist/launcher/grenade_launcher.dm b/code/modules/projectiles/guns/specialist/launcher/grenade_launcher.dm
index 0f767d679d..4cc0857907 100644
--- a/code/modules/projectiles/guns/specialist/launcher/grenade_launcher.dm
+++ b/code/modules/projectiles/guns/specialist/launcher/grenade_launcher.dm
@@ -195,14 +195,18 @@
 	msg_admin_attack("[key_name_admin(user)] fired a grenade ([fired.name]) from \a ([name]).")
 	log_game("[key_name_admin(user)] used a grenade ([name]).")
 
+	// canister rounds explode before leaving the barrel of the launcher.
+	if(istype(fired, /obj/item/explosive/grenade/high_explosive/airburst/canister))
+		var/obj/item/explosive/grenade/high_explosive/airburst/canister/canister_round = fired
+		canister_round.canister_fire(user, target)
+		return
+
 	fired.throw_range = 20
 	fired.det_time = min(10, fired.det_time)
 	fired.activate(user, FALSE)
 	fired.forceMove(get_turf(src))
 	fired.throw_atom(target, 20, SPEED_VERY_FAST, user, null, NORMAL_LAUNCH, pass_flags)
 
-
-
 //Doesn't use these. Listed for reference.
 /obj/item/weapon/gun/launcher/grenade/load_into_chamber()
 	return