CALIBER WIKI
What is .177 / 4.5mm?
4.5mm BB & pellet — The standard airgun caliber — no license under the energy limit.
.177 (4.5mm) is the standard airgun caliber: tiny steel BBs or lead pellets pushed by CO2, spring or compressed air. Almost every air pistol and air rifle on IndianGuns — Glock, Beretta, Colt and Walther replicas — is a .177.
In India, .177 airguns below the legal energy limit (dealers quote the 20-joule line) need no arms license for adults aged 18 and above.
Quick facts
- Projectile: 4.5mm steel BB or lead pellet
- Power: CO2 / spring / PCP airguns
- Use: 10m target, plinking, training
- Famous guns: virtually every replica air pistol
No arms license needed for adults (18+) as long as the airgun stays below the legal energy limit.
Buying guides
Technical specifications
Representative standard loading: Typical 8 gr domed pellet from a PCP air rifle. Figures from Wikipedia.
| Bullet diameter | 4.5 mm (.177 in) |
|---|---|
| Case length | — (waisted pellet, no case) |
| Bullet weight | 8 gr pellet (0.52 g) |
| Muzzle velocity | ≈244 m/s (≈800 ft/s) |
| Muzzle energy | ≈15 J (typical; Indian license-free limit is 20 J) |
| Origin | United States |
| Designer | Crosman et al. |
| Test barrel | Airgun barrel (varies) |
.177 / 4.5mm vs other well-known calibers
Typical muzzle energy — bars to scale. A .177 airgun pellet hits with roughly 1/25th the energy of a 9mm round.
| Caliber | .177 / 4.5mm | .22 LR | .32 ACP | 9mm Luger |
|---|---|---|---|---|
| Bullet Ø | 4.5 mm (.177 in) | 5.7 mm (.223 in) | 7.9 mm (.3125 in) | 9.01 mm |
| Bullet weight | 8 gr pellet (0.52 g) | 40 gr solid (2.6 g) | 71 gr FMJ (4.6 g) | 7.45 g FMJ (115 gr) |
| Velocity | ≈244 m/s (≈800 ft/s) | 366 m/s (1,200 ft/s) | 276 m/s (905 ft/s) | 360 m/s (1,180 ft/s) |
| Energy | ≈15 J (typical; Indian license-free limit is 20 J) | 178 J (131 ft·lbf) | 175 J (129 ft·lbf) | 481 J (355 ft·lbf) |
Bullet size, to scale
Front view of each bullet at true relative size.
.177 / 4.5mm 4.5 mm
.22 LR 5.7 mm
.32 ACP 7.94 mm
9mm Luger 9.01 mm