The accused were identified as Shahnawaj, Javed, Salman, and Januwal Khan, a police spokesman said, quoting Banswara Superintendent of Police A K Tak.
Five pistols and 10 live cartridges were seized from them, he said and added that they were booked under the Arms Act.
The four accused bought these arms earlier this month from gang members of Naeem, the kingpin of the illegal arms supplying racket who is lodged in Rajasthan's Pratapgarh jail, he said.
The gang has sold 22 items since 2012, the spokesman said.
Of these 22 items, Banswara Police have already recovered 12 arms and 10 live cartridges.