It looks like you might have a magazine issue; I'm guessing the spring isn't strong enough to cause the rounds to feed correctly after the first few rounds are gone and there's less tension on the magazine spring.
Edit: Ah, I see now that you mean you can't load more than 3 rounds into the magazine (I thought you meant the rifle was jamming after you fired three rounds). I'm guessing the spring or follower is binding on something. Try taking the magazine apart (if you can) and see what's causing it to bind up; it might just be some extra plastic that you can shave off. If that doesn't work, you should be able to send it back to the manufacturer.
And I'm guessing that you guys called them "clips" as a hold-over from the M1 Garand, which was the last American rifle that actually required clips. By the time I got to the Marines in '97, the military knew the difference and it was drummed into us. And considering our ammo came on clips to make it easier to load into our magazines, it was very important for us to know the difference between the two.
All I'm saying is that there is a distinct difference between a "clip" and a "magazine", and very few semi-auto firearms these days require the use of clips. You can sometimes use clips to make loading the magazines faster and easier, but they're not required.
The constant use of the word "clip" to mean "magazine" just reminds me of the general ignorance of firearms we see in this country today; an ignorance that drives a majority of Americans to support ridiculous laws like the Assault Weapons Ban. In my opinion, not understanding the difference between a "magazine" and a "clip" is similar to not understanding the difference between semi- and full-auto, not understanding that "assault weapons" aren't "high-powered", not understanding that the Assault Weapons Ban is just a stupid law that bans cosmetic features, and not understanding that assault rifles and machine guns are already functionally illegal in this country.
I mean no disrespect and I'm not saying you're ignorant regarding firearms, but that's just my explanation for why it annoys me when people use the word "clip" to mean "magazine".
(Also, I just noticed that this is a zombie thread from over six years ago that's been resurrected four different times over the years by four different new members.)