Fixes the XM43E1 and the M42C (#4974)

# About the pull request

they had the wrong barrel overlay giving them the normal marine spec
sniper barrel, the XM43E1 was only named that in one location which made
it spawn improperly, this has been fixxed and i went and renamed
everything relating to its old name which was the XM42B

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# Explain why it's good for the game

Visual bugs arent fun, fixing them is very important, this fixes what
was broken, so yippie
# Testing Photographs and Procedure
<details>
<summary>Screenshots & Videos</summary>

Put screenshots and videos here with an empty line between the
screenshots and the `<details>` tags.

</details>

https://imgur.com/EV52Q7S
all three snipers, with correct barrels

https://imgur.com/XiH0fSL
M42C rifle with correct barrel, in hand 

https://imgur.com/piifH2q
XM43E1 with correct barrel in hand

https://imgur.com/Y5kGftc
https://imgur.com/5IJsoS9
https://imgur.com/ZHAglSC
all items relating to the XM43E1 being correctly named and functioning
like normal

sorry i didnt feel like screenshotting every single helmet and head item
that could fit the pipe


# Changelog
:cl:

fix: fixes the XM43E1s name (previously named XM42B) and sprite, fixes
the M42C and XM43E1s barrel, correctly names several items relating to
the XM43E1

/:cl:

code/datums/supply_packs/black_market.dm

@@ -749,8 +749,8 @@ This is where the RO can reclaim their lost honor and purchase the M44 custom, t
 	dollar_cost = 10
 	containertype = /obj/structure/largecrate/black_market
 
-/datum/supply_packs/contraband/deep_storage/xm42b_pipe
-	name = "10x99mm XM42B casing"
+/datum/supply_packs/contraband/deep_storage/xm43e1_pipe
+	name = "10x99mm XM43E1 casing"
 	contains = list(/obj/item/prop/helmetgarb/bullet_pipe)
 	dollar_cost = 10
 	containertype = /obj/structure/largecrate/black_market

code/datums/supply_packs/spec_ammo.dm

@@ -109,10 +109,10 @@
 	containername = "M42A Incendiary Magazine Crate"
 	group = "Weapons Specialist Ammo"
 
-//XM42B - Disabled during testing per request.
+//XM43E1 - Disabled during testing per request.
 /*
 /datum/supply_packs/ammo_amr_marksman
-	name = "XM42B anti-materiel rifle marksman magazines crate (x5)"
+	name = "XM43E1 anti-materiel rifle marksman magazines crate (x5)"
 	contains = list(
 		/obj/item/ammo_magazine/sniper/anti_materiel,
 		/obj/item/ammo_magazine/sniper/anti_materiel,
@@ -122,7 +122,7 @@
 	)
 	cost = 30
 	containertype = /obj/structure/closet/crate/ammo
-	containername = "XM42B Anti-Materiel Magazine Crate"
+	containername = "XM43E1 Anti-Materiel Magazine Crate"
 	group = "Specialist Ammo"
 */
 //M4RA

code/game/objects/items/props/helmetgarb.dm

@@ -502,8 +502,8 @@
 	icon_state = "trimmed_wire"
 
 /obj/item/prop/helmetgarb/bullet_pipe
-	name = "10x99mm XM42B casing pipe"
-	desc = "The XM42B was an experimental weapons platform briefly fielded by the USCM and Wey-Yu PMC teams. It was manufactured by ARMAT systems at the Atlas weapons facility. Unfortunately the project had its funding pulled alongside the M5 integrated gasmask program. This spent casing has been converted into a pipe, but there is too much tar in the mouthpiece for it to be useable."
+	name = "10x99mm XM43E1 casing pipe"
+	desc = "The XM43E1 was an experimental weapons platform briefly fielded by the USCM and Wey-Yu PMC teams. It was manufactured by ARMAT systems at the Atlas weapons facility. Unfortunately the project had its funding pulled alongside the M5 integrated gasmask program. This spent casing has been converted into a pipe, but there is too much tar in the mouthpiece for it to be useable."
 	icon_state = "bullet_pipe"
 
 /obj/item/prop/helmetgarb/chaplain_patch

code/modules/client/preferences_gear.dm

@@ -350,7 +350,7 @@ var/global/list/gear_datums_by_name = list()
 	path = /obj/item/prop/helmetgarb/trimmed_wire
 
 /datum/gear/helmet_garb/bullet_pipe
-	display_name = "10x99mm XM42B casing pipe"
+	display_name = "10x99mm XM43E1 casing pipe"
 	path = /obj/item/prop/helmetgarb/bullet_pipe
 	allowed_origins = USCM_ORIGINS
 

code/modules/projectiles/gun_attachables.dm

@@ -495,6 +495,20 @@ Defined in conflicts.dm of the #defines folder.
 	accuracy_mod = HIT_ACCURACY_MULT_TIER_3
 	scatter_mod = -SCATTER_AMOUNT_TIER_8
 
+/obj/item/attachable/pmc_sniperbarrel
+	name = "sniper barrel"
+	icon = 'icons/obj/items/weapons/guns/attachments/barrel.dmi'
+	icon_state = "pmc_sniperbarrel"
+	desc = "A heavy barrel. CANNOT BE REMOVED."
+	slot = "muzzle"
+	flags_attach_features = NO_FLAGS
+	hud_offset_mod = -3
+
+/obj/item/attachable/pmc_sniperbarrel/New()
+	..()
+	accuracy_mod = HIT_ACCURACY_MULT_TIER_3
+	scatter_mod = -SCATTER_AMOUNT_TIER_8
+
 /obj/item/attachable/sniperbarrel/vulture
 	name = "\improper M707 barrel"
 	icon_state = "vulture_barrel"

code/modules/projectiles/guns/specialist/sniper.dm

@@ -337,12 +337,12 @@
 	damage_mult = BASE_BULLET_DAMAGE_MULT
 	recoil = RECOIL_AMOUNT_TIER_5
 
-/obj/item/weapon/gun/rifle/sniper/xm43e1
+/obj/item/weapon/gun/rifle/sniper/XM43E1
 	name = "\improper XM43E1 experimental anti-materiel rifle"
 	desc = "An experimental anti-materiel rifle produced by Armat Systems, recently reacquired from the deep storage of an abandoned prototyping facility. This one in particular is currently undergoing field testing. Chambered in 10x99mm Caseless."
 	icon = 'icons/obj/items/weapons/guns/guns_by_faction/uscm.dmi'
-	icon_state = "xm42b"
-	item_state = "xm42b"
+	icon_state = "xm43e1"
+	item_state = "xm43e1"
 	unacidable = TRUE
 	indestructible = 1
 
@@ -353,12 +353,12 @@
 	zoomdevicename = "scope"
 	attachable_allowed = list(/obj/item/attachable/bipod)
 	flags_gun_features = GUN_AUTO_EJECTOR|GUN_SPECIALIST|GUN_WIELDED_FIRING_ONLY|GUN_AMMO_COUNTER
-	starting_attachment_types = list(/obj/item/attachable/sniperbarrel)
+	starting_attachment_types = list(/obj/item/attachable/pmc_sniperbarrel)
 	sniper_beam_type = /obj/effect/ebeam/laser/intense
 	sniper_beam_icon = "laser_beam_intense"
 	sniper_lockon_icon = "sniper_lockon_intense"
 
-/obj/item/weapon/gun/rifle/sniper/XM42B/handle_starting_attachment()
+/obj/item/weapon/gun/rifle/sniper/XM43E1/handle_starting_attachment()
 	..()
 	var/obj/item/attachable/scope/variable_zoom/S = new(src)
 	S.icon_state = "pmcscope"
@@ -368,11 +368,11 @@
 	update_attachable(S.slot)
 
 
-/obj/item/weapon/gun/rifle/sniper/XM42B/set_gun_attachment_offsets()
+/obj/item/weapon/gun/rifle/sniper/XM43E1/set_gun_attachment_offsets()
 	attachable_offset = list("muzzle_x" = 32, "muzzle_y" = 18,"rail_x" = 15, "rail_y" = 19, "under_x" = 20, "under_y" = 15, "stock_x" = 20, "stock_y" = 15)
 
 
-/obj/item/weapon/gun/rifle/sniper/XM42B/set_gun_config_values()
+/obj/item/weapon/gun/rifle/sniper/XM43E1/set_gun_config_values()
 	..()
 	set_fire_delay(FIRE_DELAY_TIER_6 * 6 )//Big boy damage, but it takes a lot of time to fire a shot.
 	//Kaga: Adjusted from 56 (Tier 4, 7*8) -> 30 (Tier 6, 5*6) ticks. 95 really wasn't big-boy damage anymore, although I updated it to 125 to remain consistent with the other 10x99mm caliber weapon (M42C). Now takes only twice as long as the M42A.
@@ -382,7 +382,7 @@
 	damage_mult = BASE_BULLET_DAMAGE_MULT
 	recoil = RECOIL_AMOUNT_TIER_1
 
-/obj/item/weapon/gun/rifle/sniper/XM42B/set_bullet_traits()
+/obj/item/weapon/gun/rifle/sniper/XM43E1/set_bullet_traits()
 	LAZYADD(traits_to_give, list(
 		BULLET_TRAIT_ENTRY(/datum/element/bullet_trait_iff),
 		BULLET_TRAIT_ENTRY(/datum/element/bullet_trait_penetrating),
@@ -415,7 +415,7 @@
 	force = 17
 	zoomdevicename = "scope"
 	flags_gun_features = GUN_AUTO_EJECTOR|GUN_WY_RESTRICTED|GUN_SPECIALIST|GUN_WIELDED_FIRING_ONLY|GUN_AMMO_COUNTER
-	starting_attachment_types = list(/obj/item/attachable/sniperbarrel)
+	starting_attachment_types = list(/obj/item/attachable/pmc_sniperbarrel)
 	sniper_beam_type = /obj/effect/ebeam/laser/intense
 	sniper_beam_icon = "laser_beam_intense"
 	sniper_lockon_icon = "sniper_lockon_intense"

code/modules/projectiles/magazines/specialist.dm

@@ -27,14 +27,14 @@
 	default_ammo = /datum/ammo/bullet/sniper/flak
 	ammo_band_color = AMMO_BAND_COLOR_IMPACT
 
-//M42B Magazine
+//XM43E1 Magazine
 /obj/item/ammo_magazine/sniper/anti_materiel
-	name = "\improper XM42B marksman magazine (10x99mm)"
+	name = "\improper XM43E1 marksman magazine (10x99mm)"
 	desc = "A magazine of caseless 10x99mm anti-materiel rounds."
 	max_rounds = 8
 	caliber = "10x99mm"
 	default_ammo = /datum/ammo/bullet/sniper/anti_materiel
-	gun_type = /obj/item/weapon/gun/rifle/sniper/XM42B
+	gun_type = /obj/item/weapon/gun/rifle/sniper/XM43E1
 
 //M42C magazine