I guess you're a mind reader. It's pretty easy to disprove your anecdote with another one: most people I know that are for gun control are not for outright bans on them.
No, I don't read minds. I try to deduce people's motives from their actions. Now if the action of some person or group on passing some particular piece of anti-gun legislation is to immediately call for
more such legislation, then I think it's only fair to conclude that what they really want is nothing less than a complete & total ban.
As for the people you know, I see three possibilities:
1) You and they are honest about what they want;
2) You're making up a story, misunderstood their motives, etc.
3) They're lying to you.
I think #3 is both the safest and most reasonable alternative. Reasonable, because the tactic of claiming you only want a little bit, then a little bit more, and so on until you have everything is commonplace, with countless examples throughout history. Safe, because even if it turns out that they really do only want "reasonable" controls, their idea of reasonable is other people's idea of tyrannical.