OK, let me rephrase then - "I believe that the average effectiveness of the weapons possessed by those criminals who are armed with firearms in jurisdictions where firearms are heavily restricted is almost certainly much greater than the average effectiveness of the weapons possessed by those criminals who are armed with firearms in jurisdictions with comparatively permissive firearms laws"

Without wanting to weigh in on the rest of the gun debate issues, statistics don't show criminals in the UK having more effective firearms, in fact just the opposite.

More than half of the firearms offences in England&Wales involved the use of air weapons, a substantial number of the rest are imitation weapons, and only 12 of over 8,000 recorded violent crimes involved a machine gun (http://webarchive.nationalarchives.gov.uk/20160105160709/htt... table 3.02)

A study by the police of the gun crime market (http://webarchive.nationalarchives.gov.uk/20110218135832/htt...) concluded that automatic weapons were mostly used in gang warfare and as a status symbol; they're more expensive and the study noted that ammunition for all weapons was in short supply, which would make a bullet-hungry gun less attractive for other criminal usage (which is mainly to threaten).

With an imitation gun going for £20 and an automatic costing £1000, why would you choose the real gun to commit a robbery?

Cool beans, my mission is accomplished. This is a much softer claim than the one in your comment above.

edit: I changed 'weaker' to 'softer', because it's a stronger claim, it's likely to stand up to scrutiny, it's almost a banality.