You along with others doing the same would likely hand the election to the Dem if there are enough of you. Sometimes you just have to go with the lesser of two evils.
No going with the lesser of two evils guarantees your gun rights go away. Just one party will take longer to do it.
If the Republicans realize there is no penalty for being anti-gun, then they will always side with Dems on the issue.
Some times you have to take short term losses to get long term gains.