My research indicates that Kansas will restore a felon's firearms rights five years after the completion of his release from incarceration or of his probation, so long as the conviction was non-violent. (10 years for a violent) As your drug felony was non violent, if your sentence was fully discharged (completed) at least 5 years ago. You would be eligible for the automatic restoration of your state rights. Kan. Stat. Ann. 5 214204(a)(3)
As to your Federal rights. the loss of your Federal rights is technically for life, however, the government has agreed that If yours was a state conviction and the state restores all of your civil rights including your gun rights OR if you have your offense set aside, expunged or pardoned, the Federal government will lift its disability. That means you should have your federal rights back too.
You might want to make sure that you can clear a NICs check first. But if you can show official proof of your conviction and then the statute under which your rights were restored, you can appeal the Federal decision and the Federal government should lift its bar. You can find more on appealing a NICs denial here
If you are denied on appeal, the Federal government is going to require a pardon or an expungement, in order for you to restore your rights.
If you need it, here is the link to the Kansas expungement law
. It's a plain English overview, and you can look at section 4 having to do with persons convicted of a crime to see if your offense would qualify. From there, you would have to petition the court. It tells you how to go about that, if you scroll almost all the way down the page to the How Do I Get my Records Expunged Section. There is no fee to apply for a Kansas expungement and you can do it without a lawyer if you wih.
If you find that your particular felony is not one that allows you to be eligible for an expungement, the only other way to minimize the effects of your conviction would be to try to get a pardon from the governor of your state
. I have linked you to where you can find the information and forms.
There are also lawyers who specialize in this kind of law if you don't want to do this for yourself. You could price one by contacting the Kansas State Bar Association's lawyer referral service.
They can give you the going rate for an expungement and then refer you for $50 or less, to a lawyer who could do this for you. The referral fee would include a free half hour consultation with the attorney.