The hosts took a fifth-minute lead after Liam Elston powered over from close-range, a strong maul having been stopped short of the line.
Andrew Lamb slotted the extras before Rams moved further ahead at the start of the second quarter, hooker Pete Austin burrowing over from the back of a set-piece.
A sensational Tomek Pozniak try soon after saw the Polish wing beat several defenders when running in from his own half, but Chinnor got off the mark as second row Sam Gilbert nudged an Andrew Prosser chip ahead forward before grounding the ball.
Rams pull further clear
A brilliant touchline conversion reduced the arrears to 17-7, but following a terrific Rhoads burst, Max Marshall was able to burrow under the posts for a home seven-pointer with the final play of the opening 40 minutes.
Rhoads then produced a lovely arcing run to extend the lead from inside his own half, Lamb on target for 31-7 before Chinnor struck back with two tries in three minutes.
Firstly, Joe Harman powered over from close-range, before a carbon-copy effort was added to to cut the gap to 12 points.
Rams responded swiftly, however, debutant Sam Thain running in an interception from 30 metres out, only for Chinnor’s maul to again get going in making it 36-26 with a quarter-of-an-hour to play.
Marshall doubles up
The hosts gave them breathing space as Marshall crossed following a series of pick-and-goes, James Gilman with a fine nudge from the right.
Some brilliant work from Sam Bowen then saw the wing go from inside his own 22 to Chinnor’s an inside ball giving scrum-half Ollie Hodgson a simple walk-in next to the posts.
Gilman brought up the half-century, and arguably the team try of the night followed as some sublime continuity play saw the ball pass through the hands of Gillman, Aaron Tull, Marshall and Hodgson before a long pass sent Rhoads away.
Chinnor battle but Rams have final word
Another solid Gilman kick followed, but Chinnor fought to the end and grabbed a fifth try of the evening after regaining another chip ahead, Isaac Ridge eventually blasting over.
It was Rams, in the form of hat-trick hero Rhoads, though, who had the final word.
And it was a bizarre score which sealed the treble, Chinnor looking to play from behind their own try-line only for a pass to go astray and Rhoads to dot the ball down for Gilman to convert.
Rams Development next host the Royal Air Force on Wednesday, October 29.
