Anschutz and Remington 700 are regarded to be most accurate rifles in the world. NOMAN
You will have to define "sniper rifle". There is no meaning to that term, other than an accurate scope mounted rifle. That includes most hunting rifles.
Depends on how you define accuracy. Mossberg makes a durable, workmanlike hunting rifle. While it would not be my first choice for a 900 meter target rifle, in a hunting situation, it is probably more accurate than the average shooter.
The correct term is cartridge- which is the cartridge case, primer, powder, and bullet. A sniper rifle is simply an accurate, long range rifle that is used by a sniper. It may look exactly like my long range hunting rifle- since most military sniper rifles BEGAN as a civilian hunting weapon.
Depending on condition, $75-150. Very accurate and powerful hunting grade air rifle.
I actually meant a target, Sorry.. I didn't mean hunting
Your rifle is a Marlin Model 81. Value could range from $50-$145, depending on condition. Most are around $100 or so. Accurate reliable hunting grade rifle.
If a rifle is permitted for hunting, semi autos can be used in MOST states. Pennsylvania does not permit them for big game hunting. You would need to check the hunting regulations for YOUR state.
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.
From a benchrest.
Custom built
Impossible to answer as asked. Rifle, pistol, shotgun? What does accurate mean to you?
It is often accepted the Heckler and Koch PSG-1 is the most accurate sniper rifle in the world.