Possible short story from 60’s or 70’s about a man who invents a force field bubble by accident in his home using simple items then the government tries to take it away. He discovers the fields properties as he defends himself from attempts to force him to give it up by using the force fields size and opacity to incursions to defend himself.
Might it be "Gadget vs. Trend" by Christopher Anvil?
There are mentions of using the force field in actions against the government:
Staunton, Vt., February 23, 1978. Hiram Smith, a retired high school science teacher whose family has lived on the same farm since before the time of the Revolution, was ordered last fall to leave his family home.
A dam is to be built nearby, and Mr. Smith's home will be among those inundated.
At the time of the order, Mr. Smith, who lives on the farm with his fourteen-year-old grandson, stated that he would not leave "until carried out dead or helpless."
This morning, the sheriff tried to carry out the eviction order, and was stopped by a warning shot fired from the Smith house. The warning shot was followed by the flight of a small, battery-powered model plane, apparently radio-controlled, which alighted about two thousand yards from the Smith home, near an old apple orchard.
Mr. Smith called to the sheriff to get out of his car and lie down, if the car was not stasis-equipped, and in any case to look away from the apple orchard.
There was a brilliant flash, a shock, and a roar which the sheriff likened to the explosion of "a hundred tons of TNT." When he looked at the orchard, it was obscured by a pink glow and boiling clouds, apparently of steam from vaporized snow.
Mr. Smith called out to the sheriff to get off the property, or the next "wink bomb" would be aimed at him.
No one has been out to the Smith property since the sheriff's departure.
It is also used by farmers to form immovable barriers when roads are built across their farms:
Spring Corners, Iowa, January 28, 1978. Traffic is flowing once again on the Cross-State Highway.
This morning a U.S. Army truck-mounted earth auger moved up the highway and drilled a number of holes six feet in diameter, enabling large chunks of earth to be carefully loosened and both sections of the barricade to be lifted out as units. The wire, oil drums, saw horses, and big chunks of earth, which remained rigid when lifted out, are being removed to the U.S. Army Research and Development Laboratories for study. No QuietWall units have been found, and it is assumed that they are imbedded, along with their power source, inside the masses of earth.
The sheriff, the police chief of Spring Corners, and state and federal law enforcement agents are attempting to arrest Oscar B. Nelde, owner of the farm adjacent to the highway.
It is also used by robbers to make unstoppable getaway cars out of golf carts and the US government is accused of dropping millions of small force field generators over Cuba, thereby causing the cuban government a lot of trouble.
This might not be the story you had in mind, but it sprang to mind at the combination of "force field" and "fight the government "
I finally found it by searching for the "wink bomb," which is what Mr. Smith called the forcefield based atomic bomb he used against the sheriff.