diff --git a/src/ranged.cpp b/src/ranged.cpp
index af1ea219a0b4..a4503e7ff643 100644
--- a/src/ranged.cpp
+++ b/src/ranged.cpp
@@ -776,8 +776,10 @@ namespace
 auto is_mountable( const map &m, const tripoint &pos ) -> bool
 {
     // usage of any attached bipod is dependent upon terrain
-    // sandbag barricades are impassable but climbable
-    if( m.climb_difficulty( pos ) <= 5 && m.has_flag_ter_or_furn( "MOUNTABLE", pos ) ) {
+    // only allow mounting passable OR climable terrain
+    // example: sandbag barricades are impassable but climbable
+    if( ( m.climb_difficulty( pos ) <= 5 || m.passable( pos ) ) &&
+        m.has_flag_ter_or_furn( "MOUNTABLE", pos ) ) {
         return true;
     }