The weightlifter was shot in the shoulder (file photo)

A weightlifter shot himself in the shoulder after accidentally dropping his dumbbell on a bullet, in an incident Modesto police described as "suspicious, but not impossible."

The Californian muscle man told officers he was working out at home on Wednesday when he dropped one of his weights on a .22 caliber bullet. The impact on the rim of the bullet could have caused the explosion, a police officer told the Modesto Bee.

There was no gun found on the property, however police did locate the shell's casing. The veracity of the 56-year-old weightlifters' story seems to be confirmed by witnesses, who say they saw nobody leave the man's home following the shot around 9pm on Wednesday.

The man was taken to hospital to be treated for the wound, but was not seriously injured, The LA Times reports.