The Sprocket Wheel, cataloged under National Stock Number 3020-00-321-3856, is classified within Federal Supply Class 3020 (Gears, Pulleys, Sprockets, and Transmission Chain) of the Mechanical Power Transmission Equipment group. The manufacturer of record is General Dynamics-Ots, Inc. Div Ordnance and Tactical Systems. Government technical data includes 22 specifications, cited from the U.S. Government catalog. The record lists 1 manufacturer part number for this item, enabling identification through both NSN and commercial part number lookups. 2 items share a part number with this NSN in the catalog (possible match — not a government interchangeability claim). Current acquisition status: Active.
| Parameter | Value |
|---|---|
| NSN | 3020-00-321-3856 |
| Primary Part Number | 139C6319 |
| Item Name | Sprocket Wheel |
| FSC / FSG | 3020 / 30 — Gears, Pulleys, Sprockets, and Transmission Chain |
| Manufacturer | General Dynamics-Ots, Inc. Div Ordnance and Tactical Systems |
| Status | ACTIVE |
| Spline Minor Diameter | 0.438 INCHES NOMINAL IN |
| Hub Outside Diameter | 0.760 INCHES NOMINAL AA END IN |
| Design Form | PLAIN |
| Teeth Hardness Rating | 30.0 ROCKWELL C MINIMUM AND 35.0 ROCKWELL C MAXIMUM |
| Tooth Pitch | 1.086 INCHES NOMINAL IN |
| Outside Diameter | 3.250 INCHES NOMINAL IN |
| Spline Length | 0.750 INCHES NOMINAL IN |
| Style Designator | PLAIN |
| Metallic Hardness Rating and Location | 30.0 ROCKWELL C MINIMUM BODY AND 35.0 ROCKWELL C MAXIMUM BODY |
| Material Document and Classification | MIL-S-18729, COMP 4130, COND N MIL SPEC SINGLE MATERIAL RESPONSE |
| Pitch Diameter | 2.620 INCHES NOMINAL IN |
| Spline Major Diameter | 0.525 INCHES NOMINAL IN |
| Bore Type | INVOLUTE SPLINE |
| Teeth Row Quantity | 1 |
| Teeth Quantity Per Row | 4 |
| Spline Pressure Angle in Deg | 30.0 |
| Hardness Rating Test Method | ROCKWELL |
| Spline Quantity | 15 |
| Distance From Hub End to Flange End | 0.600 INCHES NOMINAL AA END IN |
| Material | STEEL COMP 4130 |
| Face Width | 0.150 INCHES NOMINAL IN |
| Spline Pitch Diameter | 0.469 INCHES NOMINAL IN |
| Acquisition Status | ACTIVE |
| DEMIL Code | DEMIL Q — CCL Item — Commerce Control List |
| Hazard | No hazard code in the DLA record (HMIC N) |
| Criticality Code | X |
| Part Number | Manufacturer |
|---|---|
| 139C6319 PRIMARY | General Dynamics-Ots, Inc. Div Ordnance and Tactical Systems (USA) |
NSN 3020-00-321-3856 is a Sprocket Wheel, manufactured by General Dynamics-Ots, Inc. Div Ordnance and Tactical Systems, classified under FSC 3020, Gears, Pulleys, Sprockets, and Transmission Chain. Status: active.
NSN 3020-00-321-3856 has 1 manufacturer part number on file: 139C6319 (General Dynamics-Ots, Inc. Div Ordnance and Tactical Systems).
2 possible matches (shared part number, not a government interchangeability claim): 3020-01-140-3265, 3020-01-228-4377. Verify interchangeability with system specifications before substitution.
Key specifications for 139C6319: Spline Minor Diameter: 0.438 INCHES NOMINAL IN; Hub Outside Diameter: 0.760 INCHES NOMINAL AA END IN; Design Form: PLAIN; Teeth Hardness Rating: 30.0 ROCKWELL C MINIMUM AND 35.0 ROCKWELL C MAXIMUM. 22 specifications are documented in the U.S. Government catalog.
No hazard code in the DLA record (HMIC N). Hazard information on this page is shown exactly as it appears in the DLA record.
NSN 3020-00-321-3856 has DEMIL Code Q. Demilitarization may be required before disposal or transfer to non-military entities.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-16.
U.S. Government catalog: edition PUBLOGDVD v12.0.0 (OCT 2026), edition date 2026-10-01, retrieved 2026-10-18.