How many shots do you get on continuos mode with your K-30?

I have a Sandisk Extreme Pro and in RAW+ with 16 meg jpeg at 3* quality the best I can seem to do is four or 5. If I go jpeg only and smallest jpeg and lowest quality I can get 7. I have seen in another thread discussing SD cards where someone said they got 8+ RAW shots on the Extreme Pro. Could there be that much variation from card to card . . .I certainly hope not.

Also, I thought the first couple times I tried I got 5 or 6 shots but then I formatted the card in camera and ever since 4 is it. I also have an Extreme III and it gets four also but takes a little longer to clear the buffer. Heck even the Ultra II I have gets 4.

Do I have something set up wrong? Seems strange that I get so few shots on the Extreme Pro especially.

Thanks for help

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Bob Corson