Robert E. Sanders, an ATF official for 24 years who is now a North Carolina lawyer specializing in firearms matters, said letter rulings are often “definitely contradictory and inconsistent,” but are necessary because the regulations being applied are ill-defined.
“It is hard to tell what ATF wants you to do without submitting your product and asking for a letter ruling,” he said. “You can’t tell what the agency has said in the past to others, because those letter rulings are generally secret. How could somebody know how to comply with the law?”
The letters come from the agency’s Firearms Technology Branch, which tests weapons and related equipment that are submitted voluntarily for compliance rulings.