Template:FtCaseyBatterySeymour
| No. | Caliber | Length | Model | Serial No. | Manufacturer | Carriage | Service Dates | Notes | |
|---|---|---|---|---|---|---|---|---|---|
| A-1 | 12" Mortar Rifle | 141.12" | 1890MI | 19 | Niles Tool Works | Mortar, M1896MII, #115, Providence Steam Engine Co. | 1902-1942 | ||
| A-2 | 12" Mortar Rifle | 141.12" | 1890MI | 18 | ? | Mortar, M1896MII, #113, | 1902-1942 | ||
| A-3 | 12" Mortar Rifle | 141.12" | 1890MI | 59 | Watervliet | Mortar, M1896MII, #134, Am. Hoist & D. Co. | 1902-1942 | ||
| A-4 | 12" Mortar Rifle | 141.12" | 1890MI | 17 | ? | Mortar, M1896MII, #114, | 1902-1942 | ||
| B-1 | 12" Mortar Rifle | 141.12" | 1890MI | 60 | Watervliet | Mortar, M1896MII, #136, Am. Hoist & D. Co. | 1902-1942 | ||
| B-2 | 12" Mortar Rifle | 141.12" | 1890 | 5 | ? | Mortar, M1896MII, #117, | 1902-1942 | ||
| B-3 | 12" Mortar Rifle | 141.12" | 1890 | 8 | Watervliet | Mortar, M1896MII, #138, Am. Hoist & D. Co. | 1902-1942 | ||
| B-4 | 12" Mortar Rifle | 141.12" | 1890MI | 53 | ? | Mortar, M1896MII, #135, | 1902-1942 | ||
| Source: Coastal Defense Study Group | |||||||||