Wow, thats some rabbit!!!!!!!!!!
OneShooter and to others that would consider an Semi-Auto
20 or more years ago in the Uk, you could use an AR180 or a similar weapon of that category, but nowdays we in this most-unpleasant land are restricted to .22 WMR-as the highest calibre we are allowed to own- in a semi or pump-action format.Personally I would use the following guns,to despatch giant rabbits with-in the UK-and these are still 100% legal:
Any pistol-calibre Marlin Lever-Action rifle
A Ruger M77 17HMR
A Ruger 10/22 or a Remington 597 in either .22LR or .22WMR.
A Silenced Mossberg 12 guage pump-action
A Remington 1100 .410 or 20 guage
A Daystate high-powered Air-rifle in either .22 or .177
An Australian copy of the Enfield N04 and N05 Jungle Carbine.
I would consider also using a:
A Southern-Gun Company LA9 or LA30 lever-action. (A copy of the Colt SMG, but includes a lever-action hinged- mechanism, instead of a semi-auto action, built into the pistol-grip of the carbine) Available in the following:9mm Parabellum and .30 calibre. Both guns have a 20 and 30 roung magazine.
A Straight-Pull AR-15 M16/A1A2/M4/A1
in 5.56mm (Purpose-built specifically for the UK market to Uk specifications.)