BG-16 fixes (#3230)

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## About The Pull Request

BG-16 ammo now costs 666 power as intended (I think) down from 1000, so
they get 30 shots instead of not 30 with an advanced/military cell

BG-16 also gets its automatic firemode back since it was lost in the
firemode refactor

## Why It's Good For The Game

fancy gun version gets less shots per cell without doing more damage
when it shouldnt do that

## Changelog

:cl:
fix: the  BG-16 is now as ammo efficient as the BG-12
fix: the BG-16 has automatic fire again
/:cl:

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---------

Signed-off-by: Theos <[email protected]>

code/modules/projectiles/guns/manufacturer/etherbor/energy_gunsword.dm

@@ -52,8 +52,11 @@
 	item_state = "pgfgun"
 	w_class = WEIGHT_CLASS_NORMAL
 
+	gun_firemodes = list(FIREMODE_SEMIAUTO, FIREMODE_FULLAUTO)
+	default_firemode = FIREMODE_SEMIAUTO
+
 	cell_type = /obj/item/stock_parts/cell/gun/pgf
-	ammo_type = list(/obj/item/ammo_casing/energy/pgf , /obj/item/ammo_casing/energy/disabler/hitscan)
+	ammo_type = list(/obj/item/ammo_casing/energy/kalix/pgf , /obj/item/ammo_casing/energy/disabler/hitscan)
 
 /obj/projectile/beam/hitscan/kalix/pgf
 	name = "concentrated energy"
@@ -64,7 +67,7 @@
 	muzzle_flash_color_override = LIGHT_COLOR_ELECTRIC_GREEN
 	impact_light_color_override = LIGHT_COLOR_ELECTRIC_GREEN
 
-/obj/item/ammo_casing/energy/pgf
+/obj/item/ammo_casing/energy/kalix/pgf
 	projectile_type = /obj/projectile/beam/hitscan/kalix/pgf
 	fire_sound = 'sound/weapons/gun/energy/kalixsmg.ogg'
 	delay = 1