When Gerry was only 2 weeks old his father, Les Hemsley, was presented with a brand new snare drum, for his son, by Professor C.F. Thiele who was founder of Canada's first drum maker, The Waterloo Music Company. Professor Thiele, considered "the father of Band Music in Canada", was also the President of the Waterloo Band Festival from 1932 to 1958. The Festival was considered the premiere band and individual solo contest of it's time in Canada. (Note: Les Hemsley was a 3 time Individual Snare Drum Champion at this event.)

Gerry's formal drum training was begun at a very early age by his father who, as well, taught a number of Championship bands in and around Toronto during the 1940's and 1950's. Les Hemsley was also the first instructor of Mr. Fred Johnson (Drum Corps Hall of Fame) who, to this day, is considered the foremost authority, historian and technician of rudimental drumming in Canada. Subsequently, in his early drum career, Gerry studied under Fred Johnson for many, many years.

Aside from numerous and varied drum lessons Gerry also studied orchestral music throughout high school and for 2 years at Humber College in Toronto.

He was the 1964 Canadian National Jr. Individual Snare Drum Champion.

Gerry's students have won the Canadian National Jr. Individual Snare Drum Championship 4 times.

He has instructed and/or arranged for Drum & Bugle Corps and Marching Bands throughout North America.

Gerry and/or his students are responsible for the drumlines of over 20 Canadian National Champions.

Gerry and/or his students have instructed and/or arranged percussion for almost every prominent Junior and Senior Drum & Bugle Corps and Marching Band in Canada during the last 35 years.

He has been an adjudicator and task force member for the CJA (Canadian Judges Association), DCA (Drum Corps Associates) and DCI (Drum Corps International).

Over the years, Gerry's students have gone on to perform and/or instruct with virtually every top twelve DCI corps including: The Cadets, Blue Devils, Santa Clara Vanguard, Phantom Regiment, Madison Scouts, Boston Crusaders, Star of Indiana, Glassmen, Carolina Crown, Crossmen, Bluecoats, Dutch Boy, Seneca Optimists, and Oakland Crusaders...a trend which continues even today.

Gerry has performed as a clinician at numerous Schools and Universities throughout Canada.

He has been a member of CADRE (Canadian Associates Drumming Rudimentary Excellence) for the past 10 years.

In 2002 Gerry performed at PASIC (Percussive Arts Society International Convention) in Columbus, Ohio as part of the "Historic Drummer's Heritage Concert".

During his percussion career Gerry has had the opportunity to instruct, perform and share the stage with the likes of such rudimental drumming legends as: Larry McCormick, Fred Johnson, John Pratt, Nick Attanasio, Tom Float, Marty Hurley, Alfons Grieder, Jim Kilpatrick, Scott Johnson, and Jeff Queen, as well as many other phenomenally great drummers too numerous to mention.

In January 2006 Gerry was recognized as a "Master Drummer" by the International Association of Traditional Drummers and awarded an "Honorary Membership" by this prestigious organization founded by the legendary rudimentalist John S. Pratt.

For the past 3 years Gerry has been a composer/arranger for CADRE's Competitive Percussion Ensemble which in September, 2006 won 1st place honours at the DCA Individual & Ensemble World Championships.