The gun in colonial America was as common as the computer and Internet of modern America. It is estimated that around sixty percent of colonial families owned a gun. So why was gun ownership so prevalent in colonial America? More importantly, to your question, why did the people of Redding value their guns? The answer is one of basic survival.
When Americans talk of gun rights today, they speak of using the weapon for protection or to guard against government tyranny. While the people of Redding felt these arguments to be valid, they were more concerned about the economic impact of the gun. The colonists used the weapon to guard against wolves harming the livestock on their farms and for hunting purposes. Colonists would also need to use the weapons when traveling the colonies to establish trade and to sell their goods. It was necessary to have weapons to guard against Native American raids when journeying through the wilderness.
The importance of the gun is established in the story when Tim asks to use his father's weapon to go off to battle. The gun was called the Brown Bess, a long gun with a bayonet attached to the end of it.
Tim is not allowed to use the gun because his father really needs it to do his daily work.