The solution is very simple;
Register EVERY gun. Minimum 5 year sentence for having a non registered gun
Min 30 day waiting period with exhausting background checks for every purchase
A tiered licensing system where it requires much more training and proficiency to acquire ANY semi auto, but it's much easier to obtain hunting rifles
Every 2 years one must pass another background check and proficiency test, if you can't pass a proficiency test, no gun for you, simple
Think of all the jobs this would create
The gun "enthusiasts" seem to know the last 5 words of the 2A, but are clueless when it comes to the first 4 words of the 2A