Police?
Army?
ATF?
In reality, nobody is going to attempt to disarm 100 million gun owners.
Also, you talk about getting rid of 2nd Amendment. How?
It takes a 38 state super-majority to ratify a constitutional amendment. Anyone voting for repeal of the 2nd Amendment would be committing political suicide.
So your proposal is not feasible.
Furthermore, the percentage of gun owners relative to the general population is getting LARGER each year. The tide is flowing AGAINST your stupid idea.