The former Manchester United striker rattled in a total of seven goal attempts against a ponderous QPR defence at Vicarage Road and could hat had a hat-trick or more.
His co striker Bruce Dyer also weighed in with a goal to complete a transformation for the Hornets - both strikers were much heralded when they arrived at the club last season but finished as bit parts to a struggling campaign.
Webber struck after 11 minutes when Neal Ardley put a superb ball over the top of the defence to send Webber clear. He rounded the keeper and opted for a placed shot and was perhaps a might fortunate that Gino Padula was unable to cut out the attempt and slid into the net with the ball.
Dyer had an easier chance a few minutes later when he spun to go clear to a Gavin Mahon pass, but sent his left-foot attempt over the bar.
Former Watford keeper Chris Day had to move swiftly to get behind another snap shot from Webber, whereas Rangers took 33 minutes to muster a goal attempt and then Martin Rowlands sent a 30-yard drive over the bar.
Rangers thought they were harshly thwarted when Watford's rookie goolkeeper Richard Lee dropped the ball under pressure from Kevin McLeod, but the referee awarded a foul, dismissing Rangers' claim for an equaliser.
The visitors had a flurry of attacks, but the nearest they came was when Kevin Gallen slid in but failed to make a connection with Tony Thorpe's cross.
Watford increased their lead after 43 minutes when Ardley fed the ball to Mahon who sent a reverse pass into the path of Paul Devlin who crossed from the byline to set up Dyer for a stooping header.
Watford made sure of all three points in the 60th minute when a header by Neil Cox was left by Dyer whose dummy took the defence with him enable to Webber to sprint clear.
After rounding the keeper he fired against the near post, but then converted the harder chance from the rebound.