One of the most powerful tactics I've used in debate is the demurer. In your instance, I would reply, "You're correct. You don't need a gun like that for hunting. In fact, I would go further and say that you don't need a gun for hunting at all, or even hunting itself."
My opponent would stand there gaping, because I was supposed to fight the particulars of his assertion. Instead, I gutted his argument by NOT opposing it. It is simply irrelevant. Because I would go on to explain that hunting is immaterial to the right to bear arms, so that the type of weapon used in hunting is even less material.
In other words, I would concede his point about hunting, then demonstrate how the argument is not over hunting but the right to keep and bear arms.
Much the same as your response ...
In the health care debate, you constantly hear "Well, there are millions of people with no health care. Don't you think they have a right to medical care too?" To which the proper response is "Absolutely. I believe they should have the same right to medical care as anyone else. But this debate isn't about health care. It's about who should PROVIDE that health care. I assert that it is neither the government's right nor its responsibility to supply health insurance to its citizens. It may be a good idea, but that's not the point."
Another trap is being asked how you feel about a group like gay people; the premise is that you must hold an opinion about people you’ve never met based upon a single trait. How about “I reserve my judgment to only those people I know or whom I know about. My judgment is grounded on more than a single trait, like sexual behavior or skin pigmentation, but is founded on character traits, like loyalty, compassion, fidelity and industry.” You don’t have to generalize about any random group that share a single trait. In fact, if you do, that’s bigotry.
Leftists also confuse privilege vs. Rights. Marriage requires a license and a licensing by both parties. Now association and assembly is a right.
Also when it comes to the urgency about Obamacare, it is one of funding vs. Delivering health.
Obamacare is not about ambulances with sirens but more with zealous IRS police brutality type needless urgency.
Each time they mention war on poverty or AIDS or environment as National Security, people are nuts to encourage that urgent police beating language. It is very deceptive. Government is about enforcement, not about services.