"Grand Slam"
The Grand Slam use to be considered the ACF 3-Move National Ty, The Southern Ty, The Northern Ty (AKA The Lakeside Ty), and The Florida Open at St. Petersburg. Of course, with the ACF 3-move only held every other year, it could only be won during that (even year), as the other three are (or were) held annually. Water Hellman won the Grand slam in 1972, and Tinsley also won it in 1982.I don't know that there is anything to call the "Grand Slam" in this current age, as the tradition of the game is dying, and not many of the current tournaments hold the prestige that these older tournaments once did, as entrants numbers are down. It seem now that our best tournaments today (last 5 years) seem to be: Tennessee Open, Illinois Open, West Tennessee - Strawberry Open, Southern Open, ACF National, North Carolina Open, District 4, and Alabama / District 5.
In 2008 Alex Moiseye won the World Match Championship at 11-Man Ballot, The ACF 3-Move National, and the Gold in Beijing.... a remarkable year !! In addition to winning the 2008 Ohio State Championship, District 3 & Pennsylvania State Open, the Ohio State Title Match Champion, and the District V & Alabama Open. This should also be considered a "Grand Slam" in today's standard!
I would also like to mention that Elbert Lowder completed his "Big Three Sweep" in 1986, winning the Florida Open, Southern States, and the Northern States.