Suggestion: create a pivot at the gunhands position. Then you'll only have to position the guns at the pivots location and rotate it the way mentioned before.
Suggestion2:
Load all guns at level start, then hide them all and only show the active one. This will prevent any pauses for loading.
Suggestion2:
Load all guns at level start, then hide them all and only show the active one. This will prevent any pauses for loading.