KEVIN Phillips crowned his 50th Baggies appearance with a brilliant two-goal blast as Tony Mowbray's men stormed into second spot with a truly five-star display.
Top scorer Phillips' fifth and sixth of the season and strike partner Ishmael Miller's third in two games earned Albion a richly-deserved 3-1 half-time lead.
And stunning second-half volleys from Robert Koren and skipper Jonathan Greening in the 57th and 65th minutes respectively wrapped up a fourth successive Championship win at The Hawthorns.
Gareth Ainsworth's 24th-minute reply - the first league goal conceded by Albion on Black Country soil this term - was the only blot on their copybook.
A sell-out home crowd lapped up the goal-fest as the visitors' first away defeat of the season left them rooted to the foot of the table.
Tuesday's disappointing Carling Cup defeat seemed like a distant memory as the five-goal blast made Albion the division's highest scorers.
The Baggies' biggest victory of the season also meant they finished September unbeaten in the league, having won four of their five Championship fixtures.
Although yesterday's results saw Albion slip a place to fourth, Mowbray's men kicked off this televised encounter knowing a victory would move them within a point of leaders Watford.
The Baggies boss made two changes from the last league outing at Scunthorpe eight days ago, with Phillips and James Morrison replacing Chris Brunt and Zoltan Gera, who both dropped to the bench.
Albion looked full of beans from the off and caused Rangers no end of problems during the opening ten minutes.
Miller used all his brute strength to shrug off Danny Cullip and charge into the box.
He centred towards the unmarked Phillips, but Zesh Rehman slid in in the nick of time to hack the ball clear, denying the ex-England hitman a simple tap-in.
The strike partners swapped roles 60 seconds later, with Phillips teeing up Miller 15 yards out.
The 20-year-old pulled the trigger first time but his scuffed effort clipped off Damion Stewart and crept just wide of the far post.
Albion went even closer from the ensuing corner, with Phillips peeling away from his marker to smash Greening's perfect centre off Martin Rowlands' knee on the goalline, onto the near post and out to safety.
The hosts continued to keep the West Londoners pegged back and their pressure paid off with two goals in a minute.
Filipe Teixeira fed Miller in the 17th minute and the 'Moston Menace' raced past Rehman before squaring to Phillips, who ghosted between two QPR defenders to tap home from three yards.
It was Phillips' 27th Baggies goal, making him the highest scorer currently on the club's books - one ahead of long-serving defender Neil Clement.
And Phillips returned the favour moments later.
Miller beat the offside trap to race onto the ex-Sunderland man's throughball before firing under Lee Camp's body and into the net.
The goal was much celebrated by England defender Micah Richards - Miller's Eastlands team-mate - who was sat in the Halfords Lane Stand.
The Baggies were in complete control - but a lapse in concentration handed John Gregory's side a 24th minute lifeline.
Dexter Blackstock leapt at the far post to head Rowlands' free-kick across the face of goal and Ainsworth held off Teixeira to poke home.
That was Rangers' first effort on goal and they soon recorded another, with Ben Sahar jinking inside Carl Hoefkens before dragging a right-footed shot well wide of the far post.
But normal service soon resumed.
Morrison sprinted onto Teixeira's lay-off and beat left-back Chris Barker before seeing an acute 15-yard drive brilliantly turned wide by Camp at his near post.
Greening whipped the corner in and the unmarked Leon Barnett powered a header towards the far post, where Stefan Moore kept it out with his thigh.
The ball bounced onto the lurking Phillips' knee and back towards Moore, who desperately hacked clear.
But it was a momentary reprieve as a moment of Phillips magic restored Albion's two-goal cushion in the 39th minute.
After Camp had done well to push away Miller's stinging 15-yard drive, Greening collected the loose ball and cleverly fed the 34-year-old marksman, who curled a delicious effort over Camp and into the far corner of the net.
QPR threatened briefly before half-time when skipper Adam Bolder whipped in a dangerous right-wing cross.
The ball appeared to be arcing towards Blackstock before Barnett intervened with a terrific clearance which snuffed out the danger.
Albion were back on the attack after the interval - but almost shot themselves in the foot in the 49th minute.
Barnett had to take evasive action after Paul Robinson under-hit his backpass.
But the ex-Luton defender's attempted clearance cannoned off Sahar's knee and fortuitously flew straight at Dean Kiely.
Back came Albion and clever play by Miller fed Teixeira on the left.
The £680,000 bargain buy found Morrison eight yards out but the ex-Middlesbrough man wastefully side-footed over the bar.
Baggies chances were now coming thick and fast and, after Rangers had failed to properly clear Robinson's centre, Morrison let fly with an 18-yard volley which Camp gathered at the second attempt.
It was finally 4-1 in the 57th minute.
Phillips raced onto Koren's sublime throughball, held off Cullip and was denied a hat-trick by Camp's smart near-post save.
However, Cullip could only head the loose ball to the edge of the box and Koren slammed it in the top corner with a ferocious left-foot volley.
Albion were not satisfied and continued to pile forward at will.
Phillips raced onto Miller's square ball and saw his low 15-yard drive deflect off Stewart and squirm wide of the far post.
From sub Chris Brunt's ensuing corner, Robinson powered a header towards the far top corner and only Camp's brilliant one-handed save denied the left-back a first goal of the campaign.
Again, it was to prove brief respite as the Baggies netted from Brunt's following 65th-minute flag-kick.
Blackstock cleared his lines with a near post header but the ball looped invitingly to Greening, who lashed an unstoppable 25-yard volley inside the bottom right-hand corner of the net.
QPR rallied in the dying stages but never looked like reducing the deficit.
Rowlands saw a long-range effort comfortably tipped over by Kiely before Bolder shot straight at the Baggies No.1 from similar distance.
Rowlands then jinked inside the box before seeing his low drive once again held by Kiely.
Sub Craig Beattie thought he'd made it six in the 85th minute when he slotted home Phillips' lay-off - but the 'goal' was wrongly ruled out for offside.
That failed to take the gloss off Albion's biggest win of the season, eclipsing the 4-0 romp against Ipswich in their last home league game.
It brought the perfect end to Zoltan Gera's 100th league appearance for the club after the Hungary star replaced Greening in the 68th minute.
ALBION (4-4-2): Kiely; Hoefkens, Barnett, Albrechtsen, Robinson; Morrison, Koren, Greening (Gera 68), Teixeira (Brunt 63); Miller (Beattie 68), Phillips. Subs not used: Steele (gk), Pele.
QPR (4-4-2): Camp; Rehman (Curtis HT), Cullip, Stewart, Barker (Bignot 60); Ainsworth, Bolder, Sahar (Ephraim 60), Rowlands; Moore, Blackstock. Subs not used: Cole (gk), Timoska.
GOALS: ALBION - Phillips (17 & 39), Miller (18), Koren (57), Greening (65). QPR - Ainsworth (24).
BOOKINGS: QPR - Curtis (foul 51), Rowlands (foul 80).
REFEREE: A D'Urso (Essex).
ATTENDANCE: 24,757.
ALBION STARMAN: Kevin Phillips.
PIC: GOAL TO DYE FOR...Phillips celebrates his sublime second with blond buddy Robinson
