MARION, Ohio (AP) – The owner and operator of a homemade cannon that exploded at a July Fourth weekend biker party, killing two men, has pleaded guilty to charges stemming from the deaths.

Timothy Bullard, 45, of Johnson, Vt., pleaded guilty in Marion County Common Pleas Court on Friday to two counts of involuntary manslaughter and one count of unlawful possession of dangerous ordnance.

Bullard could receive a sentence ranging from probation to 20 years in prison. No sentencing date has been set.

James McKinniss, 39, and Jackie Byrd, 64, both of Marion, were killed by flying pieces of metal when the makeshift cannon exploded on July 3 at the yearly event that drew about 100 bikers from around the country.

Authorities said the approximately 1-foot long steel tube was loaded with gunpowder and pieces of bread when it exploded, sending steel shards flying 200 yards in every direction.

Witnesses told investigators that the cannon was used to fire pieces of bread. The device had been fired several times over the weekend, said Marion County Prosecutor James Slagle.