Blues put in their best pre-season performance yet as they ran riot at a rain-sodden Gigg Lane.
All of Birmingham's goals arrived in the first-half as Mark Hughes' own goal was followed by a Peter Lovenkrands brace together with strikes from Chris Burke and Marlon King.
Lateef Elford-Alliyu grabbed a consolation after the break with an audacious lob, but it failed to take the gloss off a superb Blues display typified by some clinical finishing.
And speaking to bcfc.com afterwards, Lee Clark was delighted to see his team take advantage of the opportunities they carved out.
He said: "Certainly the first hour was very, very good. What I asked from the players was to be ruthless, to be clinical and decisive in the final third - they've certainty done that. We played a high pressing, tempo game as well which helped us create the chances and the lads finished them off really well.
"Probably, in all honesty, we had longer and better passages of play on Saturday. We created more chances. But as I said at the time we weren't clinical on Saturday but we were tonight and it showed you what we can be like when we've got that decisive play to our game. Obviously after the hour mark, when the substitutions were put in, it took a little bit of sting out of the game but it was important I could do that because we're monitoring the players' minutes all the time."
With Stephen Carr rested for the trip to Bury, Will Packwood came in at right-back, whilst Steven Caldwell returned at centre-back after he was rested at Cheltenham Town on Saturday.
Blues made a terrific start in the second minute thanks to Hughes diverting Burke's wicked cross into his own net.
Lovenkrands' cushioned header found Burke on the right and Hughes could do little to prevent the Scot from working his magic out wide.
The visitors doubled their lead on 16 minutes courtesy of Lovenkrands, who emphatically smashed the ball into the top corner after the Shakers defence conceded possession.
And the Dane didn't have to wait long for his second, when King laid the ball onto a plate from Packwood's perfectly weighted long ball.
The St. Andrew's outfit were very much in control throughout the opening period, restricting their npower League one hosts to a couple of long range strikes, and Burke made it 4-0 before the half was over, beating Trevor Carson's outstretched arm with a powerful shot.
Then, King prodded home from six-yards in the 43rd minute after Nathan Redmond's swerving effort was parried into the forward's path by Carson.
Moments before Clark made a triple substitution early in the second-half, Carson saved Curtis Davies' bullet header and Caldwell struck over the rebound.
With the damage already done Blues allowed Richie Barker's side to see more of the ball, and Elford-Alliyu's 35-yard lob proved to be the goal of the night on 69 minutes.
The last 20 minutes proved non eventful but it allowed Clark to assess a number of players he introduced from the bench.
Blues next face Plymouth Argyle in their penultimate friendly at Home Park on Saturday afternoon (3pm kick-off).
Bury starting XI (in numerical order): Trevor Carson, Phil Picken, Joe Skarz, Adam Lockwood, Peter Sweeney, David Worrall, Steven Schumacher, Lenell John-Lewis, Mark Carrington, Shaun Harrad, Mark Hughes.
Subs (in numerical order): Andy Bishop, Marcus Marshall, Lateef Elford-Alliyu, Efe Sodje, Max Harrop, Andrai Jones, Jordan Melia, Dalton McLaughlin, Liam Boswell, Luke McCarthy, Cameron Belford.
Blues starting XI: David Lucas, Will Packwood, Curtis Davies (Pablo Ibanez 71), Steven Caldwell, David Murphy, Chris Burke (Wade Elliott 56), Darren Ambrose (Morgaro Gomis 65), Hayden Mullins, Nathan Redmond, Peter Lovenkrands (Nikola Zigic 56), Marlon King (Akwasi Asante 56).
Subs not used: Colin Doyle, Jack Deaman, Mitch Hancox, Lee Naylor, Jake Jervis, Adam Rooney
, Darren Carter.