Here's a question about holding the shotgun. In this article (written for people working for the DOE Atmospheric Radiation Measurement program , North Slope of Alaska), they recommend holding the thumb along the right side of the stock, not over the stock. (item #2 below). Have people here found this to be good advice?
Defensive Shotgun - Remington 870 Operator's Guide
U.S. Department of Energy
Safeguards and Security
Central Training Academy
http://www.arm.gov/sites/nsa/870.stm
MARKSMANSHIP FUNDAMENTALS
1. Aiming
During the aiming process, you are concerned with correctly pointing the shotgun so the slug will hit the target in the desired spot.
1. Sight Alignment
You achieve correct sight alignment when the opt of the front sight post is exactly in the center of the rear sight aperature. If an imaginary horizontal line is drawn through the center of the rear sight aperature, the top of the front sight post will appear to touch that line. If an imaginary vertical line is drawn through the center of the rear sight aperature, the line will appear to bisect the front sight post. To obtain perfect sight alignment, focus on the front sight post. The rear sight post will appear fuzzy.
2. Sight Picture
You obtain correct sight picture when the sights are correctly aligned and the front sight is placed in the center of the aiming area. This center is commonly called "center hold" or "center of mass".
3. Flash Sight Picture
In a close-range encounter, you get flash sight picture by quickly verifying that the front sight is on the target's center of mass.
2. Holding
Several factors affect your ability to hold the shotgun steady while firing. These factors are the same for all firing positions.
1. Grip of the weak hand
The weak hand and elbow should be under the shotgun as much as possible. The strong hand grasps the pistol grip so that the grip rests in the "V" formed by the thumb and the trigger finger.
2. Grip of the strong hand
The strong thumb is correctly placed when it lies along the stock, NOT if it is wrapped around the wrist of the stock. If the thumb is wrapped around the wrist, during recoil you may hit your nose with the thumb, especially in the lower positions. The trigger finger is placed alongside the receiver and does not touch the trigger until the sights are on the target. The last three fingers around the pistol grip are quite sufficient to hold the shotgun exerting a firm rearward pull to keep the buttstock in the "pocket" of the strong shoulder.
3. Buttstock in the pocket of the shoulder
Correct placement of the buttstock in the shoulder pocket lessens the effect of recoil and helps steady the weapon allowing faster follow-up shots. Here's how to find your shoulder pocket: raise the strong elbow above the shoulder, place the fingers of your other hand under your raised armpit, and feel for the pocket with the thumb.
4. Strong side elbow
Mounting the elbow when firing helps keep the buttstock in the "pocket" of the shoulder. Always mount the elbow when you mount the shotgun. If the elbow isn't kept high, the pocket disappears and the shotgun can slide out onto the shoulder or biceps.
5. Stockweld
By consistently placing your cheek against the stock in the same place each time, you maintain a consistent relationship between the sights and your eyes. This consistency leads to increased accuracy. When a shooter's cheek is placed firmly against the stock, the shotgun and the shooter recoil together. This reduces the amount of time neede to recover between shots and aim again.
6. Lean into the shotgun
The action of bending your forward knee and leaning into the shotgun helps you make faster follow-up shots. Keep your rear leg straight, allowing it to act as a shock absorber.
3. Squeezing (pressing)
This is the act of manipulating the trigger, causing the shotgun to fire. This can and should be done without disturbing the alignment of the shotgun to the target. During the firing process, increase pressure straight to the rear on the trigger while maintaining sight alignment and sight picture. When you compress the time required to squeeze the trigger, this is called a "compressed surprise break."
4. Follow through
Following through means continuing to apply the fundamentals of marksmanship after firing a shot. This helps ensure good shot placement and allows quicker follow-up shots if necessary.