On July 7, 2017, about 1545 eastern daylight time, a Piper PA-28-180, N6653J, was substantially damaged during a forced landing to a field about 5 nautical miles southeast of Lee Gilmer Memorial Airport (GVL), Gainesville, Georgia. The private pilot was not injured. The airplane was being operated under the provisions of 14 Code of Federal Regulations Part 91 as a personal flight. Visual meteorological conditions prevailed at the time and no flight plan was filed for the flight that was destined for GVL, and originated about 1430 from Hilliard Airpark (01J), Hilliard, Florida.The pilot stated that when the flight was about 10 miles from GVL, he made a radio call to the airport and gave his location and intentions. He then started the checklist, and when he moved the mixture control, the handle felt like it was caught on something. He pushed harder on the mixture control to move to rich, and then began troubleshooting by moving the mixture control to the point where it had "hung up" to see if it would occur again. At that moment, he heard a "pop" sound followed by engine rpm decrease to idle. He attempted to do a quick check of the throttle quadrant by breaking the sides to get access, but reported the problem was not in the quadrant. He moved the mixture control from full rich to idle cut-off and also advanced full throttle, but there was no engine change. By that time, the flight was 7 miles from GVL. He made a mayday call reporting his location, and then executed a right 180° turn and began looking for a place to land. He located a nearby highway, but because it was congested, he opted to land in a field. According to the Federal Aviation Administration inspector who examined the airplane at the accident site the following day, he could not access the cockpit because the cabin entry door was locked. The left fuel tank had about 1/2 capacity, but he could not tell if any fuel remained in the right fuel tank. The airplane was recovered by the pilot. He also indicated that the pilot said the fuel selector was on the left tank position when the engine lost power. The pilot, who also held an mechanic certificate with airframe and powerplant ratings as well as an inspection authorization, reported that during his examination of the engine compartment the following day, he found the mixture control cable separated from the mixture control lever at the carburetor. He also indicated that the hardware used to secure the control to the mixture control lever were not recovered. The last 100-hour inspection of the engine was signed off by the pilot/mechanic on January 15, 2017. The pilot/mechanic reported he did inspect the engine controls in the engine compartment, and all were properly secured. Since the inspection was signed off as being completed, he had not done any additional work to the mixture control cable at the carburetor. The airplane had been operated between 30 and 40 hours since the inspection was performed.