Let me preface my remarks with the fact that I am a member of the NRA and they often do a good job fighting for gun rights. That being said, they've done some pretty stupid things also.
The NRA caved on the Brady Campaign's National Instant Check System.
The NRA supported closing the non-existent "gun show loophole" as a means to appease anti-2A groups.
The NRA supported the 1934 National Firearms Act as well as numerous state bans on concealed carry. (This was a long time ago, however)
The NRA supported expanding the Brady Insta Check System and the passage of state-level "baby Brady" bills.
These are just some examples that I can think of off the top of my head.