Sorry, I should have clarified. You don't need the totals query at all. You can do the counting/totals whatever in SSRS. If you use a simple stored procedure like

SELECT Person, Weapon, [other column]

FROM MyTable

WHERE [filter]...

then you can add a matrix to your design layout and use Person and Weapon as rows/columns and then a COUNT of [other column] to do your totals. If you had to, you could create a column in SSRS and make it equal to a constant, like "A" and then just count that.