Place the shotgun bottom side laying on your shoulder, on safe or unloaded.
DDT
The sniper shoulder is all for looks it does not effect you in any way. It does not give you extra bullets and neither does the shotgun bullets on the wrist. I hope this helps.
Yes
The spelling "shoulder" is correct (top of the arm, at the neck level).
Yes, you are correct.
The second expression is much more common.
The only way to know is to pattern your shotgun with as many different kinds of CORRECT ammunition as you can afford. Firearms will often show a marked preference for a brand or weight of shot.
Yes, you are correct.
The butt of a rifle or shotgun- the part that goes against your shoulder.
Cheek
The correct placement of rank for a non-commissioned officer's Army dress blues is centered on the left sleeve between the shoulder seam and the elbow. The shoulder sleeve insignia is centered on the left shoulder 1/2 inch below the top of the shoulder seam.
In America I have always been tought to "pass like cars" or pass left shoulder to left shoulder.
Gauge is correct.