Fixes strippers not working (#3649)

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## About The Pull Request

Fixes #3536
Fixes #3547

Ammo stacks added a check to prevent magazine to magazine filling which
also prevented directly filling guns with anything that wasnt an ammo
stack, which broke stripper clips and speedloaders. Revolvers escaped
this since they handle everything related to loading completely
differently.

This moves the strict ammo stack check down a bit so ammo holders that
are able to instantly transfer ammo between eachother can instead of
dont

## Changelog

:cl:
fix: strippers and speedloaders for rifles now work again
/:cl:

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---------

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

code/modules/projectiles/boxes_magazines/_box_magazine.dm

@@ -123,10 +123,10 @@
 	if(!can_load(user))
 		return
 
-	if(istype(attacking_obj, /obj/item/ammo_box/magazine/ammo_stack))
+	if(istype(attacking_obj, /obj/item/ammo_box))
 		var/obj/item/ammo_box/attacking_box = attacking_obj
 		for(var/obj/item/ammo_casing/casing_to_insert in attacking_box.stored_ammo)
-			if(!((instant_load && attacking_box.instant_load) || (stored_ammo.len >= max_ammo) || do_after(user, 0.5 SECONDS, attacking_box, timed_action_flags = IGNORE_USER_LOC_CHANGE)))
+			if(!((instant_load && attacking_box.instant_load) || (stored_ammo.len >= max_ammo) || istype(attacking_obj, /obj/item/ammo_box/magazine/ammo_stack) && do_after(user, 0.5 SECONDS, attacking_box, timed_action_flags = IGNORE_USER_LOC_CHANGE)))
 				break
 			var/did_load = give_round(casing_to_insert, replace_spent)
 			if(!did_load)

code/modules/projectiles/guns/ballistic.dm

@@ -233,7 +233,7 @@
 				to_chat(user, "<span class='notice'>There's already a [magazine_wording] in \the [src].</span>")
 		return
 
-	if(istype(A, /obj/item/ammo_casing) || istype(A, /obj/item/ammo_box/magazine/ammo_stack))
+	if(istype(A, /obj/item/ammo_casing) || istype(A, /obj/item/ammo_box))
 		if (bolt_type == BOLT_TYPE_NO_BOLT || internal_magazine)
 			if (chambered && !chambered.BB)
 				chambered.on_eject(shooter = user)