When crimped in the crimp groove (using .45 Colt brass) this boolit will be too long for your Colt SAA cylinder in .45 Colt. When crimped in .45 Auto Rim brass this boolit will not be too long for your Smith 1917.
The below picture that you are referring to illustrates which make of revolvers chambered in .45 Colt that this boolit will fit.
Hope this helps,