Entering the final turn of the final of 250 laps, Briscoe made contact with Reddick as the pair were fighting over the lead sending both cars spinning out of control allowing Busch to pounce.
Reddick was able to straighten out his #8 Chevrolet and continue but not before Busch – who was running far back in third – nipped him at the chequered flag by 0.330 seconds to steal the victory.
The win ends a 25-race winless streak by Busch, who now owns nine total Cup wins at the 0.533-mile track. Busch is also tied seven-time Cup champion Richard Petty’s streak of 18 straight seasons with at least one victory.
“We got one. Doesn’t matter how you get them. It’s all about getting them,” said Busch, who was greeted by a cascade of boos from the Bristol crowd. “I mean, man, I feel like Dale Earnhardt Sr. right now. This is awesome. I didn’t do anything.
“It’s just a testament to our team, Joe Gibbs Racing, Toyota … and it being fast, fast enough to stay in contention, fast enough to see those guys. I don’t know why we couldn’t fire off after it rained, both times. It just would not fire. Took it about 20 laps to get going.
“Overall, just really pumped to be back. Real pumped to get a win. This one means a lot. I can win on any surface here at Bristol. Bring it on, baby.”
Joey Logano, who won the inaugural Bristol Dirt Race last season, finished third, Kyle Larson was fourth while Ryan Blaney rounded out the top-five.
Completing the top 10 were Alex Bowman, Christopher Bell, Chase Elliott, Michael McDowell and Ty Dillon. Briscoe ended up 22nd after his clash with Reddick.
“I was running Tyler down and tried throwing a slider and didn’t expect him to drive in there on me and I got loose. I was spinning either way,” Briscoe said. “I feel terrible. I didn’t want to wreck him.”
NASCAR Bristol Dirt race results