May have a better answer later this season.....
I've never been able to breed any male less than 2 1/2 years old. Not sure on weight but those males were close in size to their female counterparts. I'd venture to guess in the 1KG to 1.5KG range. But, I have this male Rusty from 2004. He's never been a great eater as he typically will only eat mice and not multiple ones at that. Therefore a very slow grower. Bred him this year to Clover and she looks gravid, has stopped eating and heard lil heartbeats in her belly yesterday so???? I'll weigh him later tonight but he's visually only 1/2 size to my typical ready to breed 2 1/2 year old females. I'd guess around 500 - 700 grams. Clearly old enough at 4 1/2 years at begining of breeding season, now around 5 years old.
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Thanks,
Dave Colling

www.rainbows-r-us-reptiles.com
0.1 Wife (WC and still very fiesty)
0.2 kids (CBB, a big part of our selective breeding program)
LOL, to many snakes to list, last count (05/26/2009):
36.51 BRB
29.42 BCI
And those are only the breeders 
lots.lots.lots feeder mice and rats 

