I believe Dave is quite correct regarding 'DS'
A good collection of hang tags have been shown here, and some indicate DuPont Bulk, some only 'Bulk', and on some the powder is not indicated
c. 1924
c. 1928 with DuPont Oval
BTW Dense Smokeless had significantly higher pressures than Bulk; period pressures to which 10% was added for modern transducer numbers
1 1/8 oz. 3 Drams BULK Smokeless was 6000 - 8000 psi.
1 1/8 oz. 3 Dr. Eq. of DENSE Smokeless was 8,500 - 10,000 psi.
1 1/8 oz. 3 1/4 Dr. BULK Smokeless was about 8500 psi.
1 1/8 oz. 3 1/4 Dr. Eq. DENSE Smokeless was 9500 - 10,500 psi.
1 1/4 oz. 3 1/2 Dr. BULK Smokeless was about 11,500 psi
1 1/4 oz. 3 1/2 Dr. Eq. DENSE Smokeless was 12,500 psi