I have 3 Glock 17 mags left over from when I carry a 17 for a duty weapon, I have been thinking about turning back to the dark side and purchacing a 17 and maybe a 20sf. I thought the matches looked cool and 9mm is cheaper to reload for. I have be using 124 gr. bullets for 9mm but have never experimented with 147's. Would the 147 gr. be better for knocking the plates ? 
Remember, the dark side has better cookies.

As for 147s, they are new to me. I usually shoot 124s, but bought a box of the heavier Golden Sabers because they were on sale. They group the same, and working on the theory that bigger is better for SD, I'll probably stick with them. For range work though, if its ringing plates I can't imagine it would make much difference (though this depends on the range, more foot pounds vs more drop and less velocity at the extended ranges). I might even look at Speer Lawman TMJ. They are supposed to very accurate and as a bonus they are fairly inexpensive. I've shot some and like them, but I generally shoot double taps at silhouettes, so I'm not trying to measure dime size groups. Just a thought.
FQ13