I've discussed these types of individuals several times before. The most famous case is that of Jim Zumbo. For those of you unfamiliar w/ this bit of firearm history, a few years ago, Jim Zumbo, a prominent hunter and shooter w/ endorsements, TV shows, you name it, called semi-auto sporters like AR-15's "Terrorist Rifles" and felt they should be banned. This got linked to AR15.com and w/i a week, he had been dumped by all of his sponsors and his shows canceled.
Unfortunately he's not alone. Invariably the conversation w/ these types of individuals starts out w/, as the title says, "I'm a gun owner but..." and then goes downhill from there. The most common form that I've encountered is a hunter who doesn't see a 'need' for 'assault weapons' and/or pistols combined w/ a dislike for the 'extremist' NRA. The reasons for their opposition usually contains the traditional Brady-esque talking points like 'bullet hoses', supporting registration, etc. which is all OK because they'll 'never come after my huntin' guns'. This is also the same type of individual that the 'American Hunters and Shooters Assoc.' preyed upon to get what little membership they had.
These are some of the most difficult individuals to debate w/ in that they are firearm owners so they know and understand most of the nomenclature but they're rooted in their own selfishness/bigotry so are difficult to convince. We can't just laugh at them or dismiss them like we can w/ most of the hard-core gun control advocates.
I'll admit that I've had very little luck in this endeavor. What I have had though has come from showing them that 'Yes Virginia, they ARE after your hunting guns' such as the Joyce Funded VPC trying to re-label bolt action rifles as 'Intermediate Sniper Rifles' or the statements by the president of IANSA, Rebecca Peters and which US organizations belong to her group. And still the discussion usually loops back to the 'need' claim and 'they won't ban these' arguments.
So who has had luck w/ this class and how have you done it? Conversely, what nonsense have you encountered?