CLYDESDALE BANK 40, The Oval:
Surrey 386-3 (38 ovs) beat Glamorgan 187-5 (20 ovs) by 39 runs (D/L method)
Hamilton-Brown's 115 came from just 69 balls, with 12 fours and five sixes
Surrey broke the record for the highest score in 40-over cricket in beating Glamorgan by 39 runs on the Duckworth-Lewis method in the CB 40 at The Oval.
Rory Hamilton-Brown (115) and Steven Davies (88) took Surrey to 386-3 after rain reduced the hosts to 38 overs.
Mark Ramprakash (85 no) and Matt Spriegel (56 no) also contributed as Surrey passed the 377-9 posted by Somerset against Sussex in 2003.
More rain left Glamorgan 20 overs to get 227, but they fell short on 187-5.
After a delayed start, Glamorgan captain Jamie Dalrymple won the toss and invited the home side to bat.
But the visitors were punished by a first-wicket stand of 190 between Davies and Hamilton-Brown, who hit 12 fours and five sixes in his maiden limited-overs century.
The most impressive scoring was to come at the end of the Surrey innings, with Ramprakash and Spriegel sharing an unbroken fourth-wicket stand of 142.
Former England man Ramprakash needed just 46 balls for his 85, hitting 10 fours and two sixes, as 70 runs came from the final fours overs.
Not one of the Glamorgan bowlers was able to escape the carnage, spinner Dean Cosker conceding 80 runs from his eight overs, seamer Huw Waters going for 73 off eight and Mark Cosgrove 54 off five.
Rain shortly into the Glamorgan reply revised their target, which was never threatened.
Despite a 55-ball 88 from Cosgrove and Dalrymple's 54 from 23 balls - the fastest half-century in Glamorgan history in 40 overs - the visitors closed on 187-5, with off-spinner Gareth Batty picking up 3-44.
Surrey climb to second in Group A, a point behind Somerset, while Glamorgan remain sixth.