diff --git a/src/p_local.h b/src/p_local.h
index a69f2549dd..eb69a23c7e 100644
--- a/src/p_local.h
+++ b/src/p_local.h
@@ -425,7 +425,7 @@ void	P_TraceBleed (int damage, fixed_t x, fixed_t y, fixed_t z, AActor *target,
 void	P_TraceBleed (int damage, AActor *target, angle_t angle, int pitch);
 void	P_TraceBleed (int damage, AActor *target, AActor *missile);		// missile version
 void	P_TraceBleed (int damage, AActor *target);		// random direction version
-void	P_RailAttack (AActor *source, int damage, int offset, int color1 = 0, int color2 = 0, float maxdiff = 0, bool silent = false, const PClass *puff = NULL, bool pierce = true);	// [RH] Shoot a railgun
+void	P_RailAttack (AActor *source, int damage, int offset, int color1 = 0, int color2 = 0, float maxdiff = 0, bool silent = false, const PClass *puff = NULL, bool pierce = true, angle_t angleoffset = 0, angle_t pitchoffset = 0);	// [RH] Shoot a railgun
 bool	P_HitFloor (AActor *thing);
 bool	P_HitWater (AActor *thing, sector_t *sec, fixed_t splashx = FIXED_MIN, fixed_t splashy = FIXED_MIN, fixed_t splashz=FIXED_MIN, bool checkabove = false, bool alert = true);
 void	P_CheckSplash(AActor *self, fixed_t distance);
diff --git a/src/p_map.cpp b/src/p_map.cpp
index 3ee9b15f29..b19c04e7b9 100644
--- a/src/p_map.cpp
+++ b/src/p_map.cpp
@@ -3769,7 +3769,7 @@ static bool ProcessNoPierceRailHit (FTraceResults &res)
 //
 //==========================================================================
 
-void P_RailAttack (AActor *source, int damage, int offset, int color1, int color2, float maxdiff, bool silent, const PClass *puffclass, bool pierce)
+void P_RailAttack (AActor *source, int damage, int offset, int color1, int color2, float maxdiff, bool silent, const PClass *puffclass, bool pierce, angle_t angleoffset, angle_t pitchoffset)
 {
 	fixed_t vx, vy, vz;
 	angle_t angle, pitch;
@@ -3780,8 +3780,8 @@ void P_RailAttack (AActor *source, int damage, int offset, int color1, int color
 
 	if (puffclass == NULL) puffclass = PClass::FindClass(NAME_BulletPuff);
 
-	pitch = (angle_t)(-source->pitch) >> ANGLETOFINESHIFT;
-	angle = source->angle >> ANGLETOFINESHIFT;
+	pitch = ((angle_t)(-source->pitch) + pitchoffset) >> ANGLETOFINESHIFT;
+	angle = (source->angle + angleoffset) >> ANGLETOFINESHIFT;
 
 	vx = FixedMul (finecosine[pitch], finecosine[angle]);
 	vy = FixedMul (finecosine[pitch], finesine[angle]);
@@ -3801,7 +3801,7 @@ void P_RailAttack (AActor *source, int damage, int offset, int color1, int color
 		shootz += 8*FRACUNIT;
 	}
 
-	angle = (source->angle - ANG90) >> ANGLETOFINESHIFT;
+	angle = ((source->angle + angleoffset) - ANG90) >> ANGLETOFINESHIFT;
 	x1 += offset*finecosine[angle];
 	y1 += offset*finesine[angle];
 
@@ -3857,10 +3857,10 @@ void P_RailAttack (AActor *source, int damage, int offset, int color1, int color
 		else
 		{
 			spawnpuff = (puffclass != NULL && puffDefaults->flags3 & MF3_ALWAYSPUFF);
-			P_SpawnBlood (x, y, z, source->angle - ANG180, damage, RailHits[i].HitActor);
+			P_SpawnBlood (x, y, z, (source->angle + angleoffset) - ANG180, damage, RailHits[i].HitActor);
 			P_TraceBleed (damage, x, y, z, RailHits[i].HitActor, source->angle, pitch);
 		}
-		if (spawnpuff) P_SpawnPuff (source, puffclass, x, y, z, source->angle - ANG90, 1, PF_HITTHING);
+		if (spawnpuff) P_SpawnPuff (source, puffclass, x, y, z, (source->angle + angleoffset) - ANG90, 1, PF_HITTHING);
 
 		if (puffDefaults && puffDefaults->PoisonDuration != INT_MIN)
 			P_PoisonMobj(RailHits[i].HitActor, thepuff ? thepuff : source, source, puffDefaults->PoisonDamage, puffDefaults->PoisonDuration, puffDefaults->PoisonPeriod);
@@ -3874,7 +3874,7 @@ void P_RailAttack (AActor *source, int damage, int offset, int color1, int color
 		SpawnShootDecal (source, trace);
 		if (puffclass != NULL && puffDefaults->flags3 & MF3_ALWAYSPUFF) 
 		{
-			P_SpawnPuff (source, puffclass, trace.X, trace.Y, trace.Z, source->angle - ANG90, 1, 0);
+			P_SpawnPuff (source, puffclass, trace.X, trace.Y, trace.Z, (source->angle + angleoffset) - ANG90, 1, 0);
 		}
 
 	}
diff --git a/src/thingdef/thingdef_codeptr.cpp b/src/thingdef/thingdef_codeptr.cpp
index 69333c75f8..d0319a9920 100644
--- a/src/thingdef/thingdef_codeptr.cpp
+++ b/src/thingdef/thingdef_codeptr.cpp
@@ -1207,7 +1207,8 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_CustomPunch)
 enum
 {	
 	RAF_SILENT = 1,
-	RAF_NOPIERCE = 2
+	RAF_NOPIERCE = 2,
+	RAF_EXPLICITANGLE = 4,
 };
 
 //==========================================================================
@@ -1217,7 +1218,7 @@ enum
 //==========================================================================
 DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_RailAttack)
 {
-	ACTION_PARAM_START(8);
+	ACTION_PARAM_START(10);
 	ACTION_PARAM_INT(Damage, 0);
 	ACTION_PARAM_INT(Spawnofs_XY, 1);
 	ACTION_PARAM_BOOL(UseAmmo, 2);
@@ -1225,7 +1226,9 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_RailAttack)
 	ACTION_PARAM_COLOR(Color2, 4);
 	ACTION_PARAM_INT(Flags, 5);
 	ACTION_PARAM_FLOAT(MaxDiff, 6);
-	ACTION_PARAM_CLASS(PuffType, 7);	
+	ACTION_PARAM_CLASS(PuffType, 7);
+	ACTION_PARAM_ANGLE(Spread_XY, 8);
+	ACTION_PARAM_ANGLE(Spread_Z, 9);
 
 	if (!self->player) return;
 
@@ -1237,7 +1240,21 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_RailAttack)
 		if (!weapon->DepleteAmmo(weapon->bAltFire, true)) return;	// out of ammo
 	}
 
-	P_RailAttack (self, Damage, Spawnofs_XY, Color1, Color2, MaxDiff, (Flags & RAF_SILENT), PuffType, (!(Flags & RAF_NOPIERCE)));
+	angle_t angle;
+	angle_t slope;
+
+	if (Flags & RAF_EXPLICITANGLE)
+	{
+		angle = Spread_XY;
+		slope = Spread_Z;
+	}
+	else
+	{
+		angle = pr_crailgun.Random2() * (Spread_XY / 255);
+		slope = pr_crailgun.Random2() * (Spread_Z / 255);
+	}
+
+	P_RailAttack (self, Damage, Spawnofs_XY, Color1, Color2, MaxDiff, (Flags & RAF_SILENT), PuffType, (!(Flags & RAF_NOPIERCE)), angle, slope);
 }
 
 //==========================================================================
@@ -1249,12 +1266,13 @@ enum
 {
 	CRF_DONTAIM = 0,
 	CRF_AIMPARALLEL = 1,
-	CRF_AIMDIRECT = 2
+	CRF_AIMDIRECT = 2,
+	CRF_EXPLICITANGLE = 4,
 };
 
 DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_CustomRailgun)
 {
-	ACTION_PARAM_START(8);
+	ACTION_PARAM_START(10);
 	ACTION_PARAM_INT(Damage, 0);
 	ACTION_PARAM_INT(Spawnofs_XY, 1);
 	ACTION_PARAM_COLOR(Color1, 2);
@@ -1263,6 +1281,8 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_CustomRailgun)
 	ACTION_PARAM_INT(aim, 5);
 	ACTION_PARAM_FLOAT(MaxDiff, 6);
 	ACTION_PARAM_CLASS(PuffType, 7);
+	ACTION_PARAM_ANGLE(Spread_XY, 8);
+	ACTION_PARAM_ANGLE(Spread_Z, 9);
 
 	AActor *linetarget;
 
@@ -1329,7 +1349,21 @@ DEFINE_ACTION_FUNCTION_PARAMS(AActor, A_CustomRailgun)
 
 	angle_t angle = (self->angle - ANG90) >> ANGLETOFINESHIFT;
 
-	P_RailAttack (self, Damage, Spawnofs_XY, Color1, Color2, MaxDiff, (Flags & RAF_SILENT), PuffType, (!(Flags & RAF_NOPIERCE)));
+	angle_t angleoffset;
+	angle_t slopeoffset;
+
+	if (Flags & CRF_EXPLICITANGLE)
+	{
+		angleoffset = Spread_XY;
+		slopeoffset = Spread_Z;
+	}
+	else
+	{
+		angleoffset = pr_crailgun.Random2() * (Spread_XY / 255);
+		slopeoffset = pr_crailgun.Random2() * (Spread_Z / 255);
+	}
+
+	P_RailAttack (self, Damage, Spawnofs_XY, Color1, Color2, MaxDiff, (Flags & RAF_SILENT), PuffType, (!(Flags & RAF_NOPIERCE)), angleoffset, slopeoffset);
 
 	self->x = saved_x;
 	self->y = saved_y;
diff --git a/wadsrc/static/actors/actor.txt b/wadsrc/static/actors/actor.txt
index b6ef922657..3f8396ea19 100644
--- a/wadsrc/static/actors/actor.txt
+++ b/wadsrc/static/actors/actor.txt
@@ -185,7 +185,7 @@ ACTOR Actor native //: Thinker
 	action native A_Jump(int chance = 256, state label, ...);
 	action native A_CustomMissile(class<Actor> missiletype, float spawnheight = 32, int spawnofs_xy = 0, float angle = 0, int flags = 0, float pitch = 0);
 	action native A_CustomBulletAttack(float spread_xy, float spread_z, int	numbullets, int damageperbullet, class<Actor> pufftype = "BulletPuff", float range = 0, int flags = 0);
-	action native A_CustomRailgun(int damage, int spawnofs_xy = 0, color color1 = "", color color2 = "", int flags = 0, bool aim = false, float maxdiff = 0, class<Actor> pufftype = "BulletPuff");
+	action native A_CustomRailgun(int damage, int spawnofs_xy = 0, color color1 = "", color color2 = "", int flags = 0, bool aim = false, float maxdiff = 0, class<Actor> pufftype = "BulletPuff", float spread_xy = 0, float spread_z = 0);
 	action native A_JumpIfHealthLower(int health, state label);
 	action native A_JumpIfCloser(float distance, state label);
 	action native A_JumpIfTracerCloser(float distance, state label);
diff --git a/wadsrc/static/actors/constants.txt b/wadsrc/static/actors/constants.txt
index dcf029ca91..27a23fea67 100644
--- a/wadsrc/static/actors/constants.txt
+++ b/wadsrc/static/actors/constants.txt
@@ -84,6 +84,7 @@ const int MRF_UNDOBYDEATHSAVES = 2048;
 // Flags for A_RailAttack and A_CustomRailgun
 const int RGF_SILENT = 1;
 const int RGF_NOPIERCING = 2;
+const int RGF_EXPLICITANGLE = 4;
 
 // Flags for A_Mushroom
 const int MSF_Standard = 0;
diff --git a/wadsrc/static/actors/shared/inventory.txt b/wadsrc/static/actors/shared/inventory.txt
index 22cd69e6fa..a61519df0a 100644
--- a/wadsrc/static/actors/shared/inventory.txt
+++ b/wadsrc/static/actors/shared/inventory.txt
@@ -10,7 +10,7 @@ ACTOR Inventory native
 	action native A_CustomPunch(int damage, bool norandom = false, int flags = CPF_USEAMMO, class<Actor> pufftype = "BulletPuff", float range = 0, float lifesteal = 0);
 	action native A_FireBullets(float spread_xy, float spread_z, int numbullets, int damageperbullet, class<Actor> pufftype = "BulletPuff", int flags = 1, float range = 0);
 	action native A_FireCustomMissile(class<Actor> missiletype, float angle = 0, bool useammo = true, int spawnofs_xy = 0, float spawnheight = 0, bool aimatangle = false, float pitch = 0);
-	action native A_RailAttack(int damage, int spawnofs_xy = 0, int useammo = true, color color1 = "", color color2 = "", int flags = 0, float maxdiff = 0, class<Actor> pufftype = "BulletPuff");
+	action native A_RailAttack(int damage, int spawnofs_xy = 0, int useammo = true, color color1 = "", color color2 = "", int flags = 0, float maxdiff = 0, class<Actor> pufftype = "BulletPuff", float spread_xy = 0, float spread_z = 0);
 	action native A_Light(int extralight);
 	action native A_Light0();
 	action native A_Light1();