Your pool deaths are inflated. The 390 is over 3 years 07-09. And gun deaths spike after age 14 where I presume pool drowning a continue to fall. Further, guns lead to very large injury numbers which I'm guessing greatly exceed pool-related injuries even more. Pools aren't that dangerous.
The 390 is the annual average number for those 3 years, not total. According to wonder.cdc.gov, for ages 0-14, there were 334 pool deaths in 2008 alone.
