You're hitting the buffer. It's normal.

Take this as a top tip: dont use 24MPix setting. A medium setting of sub-20MPix is very very sufficient for your needs. And why do you need 12 fps shoot anyway? Not that you're taking shots of 100m dash finishing line. Time your shot bursts. A normal high continuous of 4-5 bursts a click is very sufficient for everyday use. I dont even need anything above 4 in most cases.
The more you burst, the more shots you need to filter out later in the computer.
And it has nothing to do with what lens you use.

But you said you shot 12 then hang, well, I'm not sure about your definition of hang. Whether is it really hang as in you need to plug out the battery or just that the camera's buffer is reached and its taking time to write it to the card.

But by right, the camera IS supposed to be able to go 12fps of 24 megapixels for 1 second before the buffer is maxed out.

Have you tried removing the battery from the battery compartment?

A 55 Newbie report in.....

Hi wanna ask any A77 user.
My A77 come with Sony SDHC 16GB, Class4.

Whenever after i shoot a pic, and I wanna delete immediately after preview, it will say something like, cannot delete as card is accessing or something..........anyone experience this? Will Class10 card be faster?

Please advice