Yes those weights are accurate. I always figure about 100 grams a month so they're pputting on good weight. Careful not to over feed them though. Some people power feed to put on weight so they can breed sooner (not saying your doing this) but this can cause adverse affects to the breeding devolopment. Obese snakes make horrible breeders. And somepeople say snakes will eat when they're hungry but they are opportunistic feeders they will eat if given food unless they're fasting for some reason. But I feed my girls twice a week too they eat like beasts. Id say your on a good schedule and they're gaining weight nicely!