Each weapon will exhibit a preference for one or more loads. The only way to know is to shoot as many different types as you can.
Assuming you mean the Remington 870 shotgun, with a scope- is your barrel rifled? If so, sabot slugs are generally the most accurate. If smoothbore, then rifled slugs will be most accurate.
Impossible to answer as asked. Rifle, pistol, shotgun? What does accurate mean to you?
.20 grams
The most popular magazine featuring guns and ammunition is "Guns and Ammo." Other popular gun and ammunition magazines include "Handguns" and "Shotgun News."
In the U.S. there is nothing specific needed in most states, but you have to 18 to purchase shotgun and rifle ammo, and 21 to purchase handgun ammo, so you might be asked for ID. Illinois, and I think a couple of other states, require residents to have an ID card to purchase ammo.
Well all the stores are closed because of the zombie apocalypse, and you need to conserve ammo! That is probably the most improtant part of Undead Nightmare! The only way you can get ammo is by killing Zombies who have ammo on them.
For out of the box ammo I've found Winchester CXP2 170 grain power points to be excellent on deer.
A Winchester 101 shotgun was used primarily for hunting. The best and most accurate way to find out the value of a firearm is to check with a gun dealer.
Completely depends on the ammunition you use. The long barrel tends to be just a little slower with most .22 ammunition but they are a highly accurate rifle with most ammo....
Depends on the firearm, what you are shooting, and where you are. With a rifle, firing from a supported position, such as a benchrest is the most accurate. In the field, the prone position is most accurate. However, that does not work well if you are in waist deep grass, or duck hunting with a shotgun. With a handgun, a two handed shooting stance is most accurate, and using a support makes that better.
If patented in 1913 the shotgun is most likely was made before 1920. There is not really any way to get an accurate date without knowing more about the gun.
Yes it is the most powerful shotgun.