The Liberals under J.T. has proposed a ban on assault style weapons (not assault weapons, mind you which are already banned) that so far has cost over $70M without guns being collected. The estimate cost is over $800M to collect them.
The last time we had a gun control fantasy was also under the Liberals. They proposed a long gun registry that they estimated would cost $2M a year. By the time it was cancelled 20 years later, the total cost was over $2B.