diff --git a/wadsrc/static/zscript/actors/inventory/weapons.zs b/wadsrc/static/zscript/actors/inventory/weapons.zs
index 9c3519b48..8e1801600 100644
--- a/wadsrc/static/zscript/actors/inventory/weapons.zs
+++ b/wadsrc/static/zscript/actors/inventory/weapons.zs
@@ -994,7 +994,7 @@ class Weapon : StateProvider
 	//
 	//===========================================================================
 
-	virtual bool DepleteAmmo(bool altFire, bool checkEnough = true, int ammouse = -1)
+	virtual bool DepleteAmmo(bool altFire, bool checkEnough = true, int ammouse = -1, bool forceammouse = false)
 	{
 		if (!(sv_infiniteammo || (Owner.FindInventory ('PowerInfiniteAmmo', true) != null)))
 		{
@@ -1006,7 +1006,7 @@ class Weapon : StateProvider
 			{
 				if (Ammo1 != null)
 				{
-					if (ammouse >= 0 && bDehAmmo)
+					if (ammouse >= 0 && (bDehAmmo || forceammouse))
 					{
 						Ammo1.Amount -= ammouse;
 					}
diff --git a/wadsrc/static/zscript/actors/mbf21.zs b/wadsrc/static/zscript/actors/mbf21.zs
index 1a8f76fbb..2a703feac 100644
--- a/wadsrc/static/zscript/actors/mbf21.zs
+++ b/wadsrc/static/zscript/actors/mbf21.zs
@@ -430,7 +430,7 @@ extend class Weapon
 		if (!weap) return;
 
 		if (consume == 0) consume = -1;
-		weap.DepleteAmmo(weap.bAltFire, false, consume);
+		weap.DepleteAmmo(weap.bAltFire, false, consume, true);
 	}
 
 	//