Private James Farrell, 18, plunged a knife into the bed of the "ringleader" of a group of fellow trainees who were allegedly bullying him at Catterick Garrison in North Yorkshire.
The blow was aimed at Rifleman Curtis Horbury's head and he had to roll out of the way to avoid being stabbed, an earlier court martial hearing at Colchester Garrison in Essex heard.
Farrell said he had no intention of hitting him with the knife and just wanted to scare him to make Rifleman Horbury leave him alone, but was found guilty following a three-day trial.
Farrell, who is from Halifax and was with the 2nd Infantry Training Battalion, said he had "lost it" before the incident on November 13 2016.
He will also be sentenced for ammunition offences at Colchester Garrison on Monday.
Farrell has admitted possessing 42 rounds of live ammunition, and 30 rounds of blank ammunition.