let me correct my earlier comment to match your correction. i used the UK's population instead of england and wales only, so it should be 56,000,000. gun crime didn't rise consistently over the decade. it was slightly higher in 2002 than in 2009. the correct rate for the most recent year is 17.6 per 100,000 people, which is still considerably less than the US rate of 32.
it's funny that you try to credit the heller decision for the drop in DC murders. the graph you posted shows it peaked at nearly 500 in 1991 and fell in most years after that, with small upticks in 1993, 1996, 2002, and 2008, when the high court made its decision, by which time the number had already fallen below 200.