but ...

DECLARE @T table (data char(1))

Insert @T (data) values ('A')
Insert @T (data) values ('a')
Insert @T (data) values ('B')
Insert @T (data) values ('b')

select * from @T where data like '[ABCDEFG]'
select * from @T where data like '[A-G]' collate Latin1_General_BIN


does give the desired result. And no need to change the table definition