Last Dates for "S" and "W" Marked Projectiles?

Does anyone know approx. what the latest years U.S.C.Co. and W.R.A.Co. projectiles were impressed with an “S” or “W” respectively?

Thanks,
Dave

According to Dan Shuey, WRA Co. marked their jacketed bullets with a ‘W’ from 1902 to February of 1932.

Roundsworth,

Thank you for that information.

Dave