Here are two analyses I did a few years back that can shed some light on the question.
I hope to present soon a new analysis Statistics Canada data that bear on this question, but, unfortunately, the results aren’t ready yet.
The Long-Gun Registry and Spousal Homicide
This paper is a brief analysis of a special request to Statistics Canada, made in July 2011, concerning female victims of spousal homicides (1995 – 2009). This study updates results from an earlier study I did in 2010 (SSRN #1599705). No support was found for the claim that the long-gun registry has been effective. As far as it can be determined, the long-gun registry has not saved a single woman’s life.
Bill C-391 – Countering Ten Misleading Claims
The statistics provided in this presentation to the Committee of the Canadian House of Commons that was evaluating Bill C-391 clearly shows that the long-gun registry has not been effective in reducing criminal violence and most especially that it has not saved lives. The multiple murders by shooting that have occurred since the registry was put in place prove that it is a waste of time and money.