Gate defeated another of the promotion hopefuls to climb to ninth in the Hallmark Security League with this third successive premier division win.
A double from Gary Pett and a goal from the returning Max Rothwell saw Gate beat a Charnock side who had equalised early in the second half.
Manager Andy Clarkson made one change to the side that beat Abbey Hey as Ryan Riley replaced the unavailable Jake Higham.
Gate would be forced into an early change when Seydou Bamba suffered a nasty-looking elbow in the eye after four minutes, though he was okay after treatment.
Bamba was replaced by midfielder Max Rothwell, who made an instant impact when he found Pett, who volleyed straight at the keeper after 13 minutes.
The striker opened the scoring six minutes later, when Isaac Sincair collected Scott Harries’ pass down the left and delivered a pinpoint cross f0r Pett to glance a header home.
Clarkson was sent to the stands for losing his cool after Gate were denied a penalty for a foul on Riley.
His mood won’t have improved four minutes before the break, when Dean Ing headed home a corner only to see the goal disallowed because of a foul.
The closest the visitors came to an equaliser before half-time was when former Gate winger Alex Ralph cut inside but fired over.
Gate keeper Ben Fletcher was called into action early in the second half, tipping over David Prout’s shot, but Charnock beat him on 53 minutes, when top scorer Carl Grimshaw scored his 41st of the season from a defence-splitting pass.
Gate were back in front within a minute as Riley’s cross was deflected into the path of Pett, who kneed home his second at the back post.
Riley almost set up Sinclair for another but the winger shot straight at the keeper.
Sinclair made amends on 63 minutes, when his through-ball found Maxwell and he beat the last man before slotting home.
The visitors had a chance to get back into the game with 10 minutes left. Alex Colquhoun conceded a penalty for a foul but Fletcher guessed right to save the spot-kick.
A delighted Clarkson said: “We controlled the game really well and played some really nice football. Gate lost to Charnock 5-2 at the start of the season, so this shows how far these lads have come.”
Gate travel to bottom club Barnton on Wednesday.
Gate: Fletcher, Gray, Bamba, Rossall, Colquhoun, Riley, Richards, Ing, Sinclair, Harries, Pett; Subs: Rothwell, Charnley, Finlayson, Clarkson, Salthouse.