I was given the Freedom with a $5500 initial CL. I reconned it at the time of approval and asked for a higher limit, took another hard pull, and the CLI was declined. The reason they gave me was prior late payments on a Chase account and other accounts (I had a series of lates, some 120+, four years ago). They wanted to see how I did with that limit first.
Fast forward to last weekend. I applied for a second Chase card, the CSP. Initial CL was $29,700. I had used my Chase Freedom modestly, running about $7000 total through it. I carried a pretty high balance for a while taking advantage of the 0% promo APR. I had paid it off completely before applying for the CSP. There was about 8 months between applying for Freedom and CSP.
So I know there are some differences as you're asking about initial CLs of $500, but at least in my experience, after seeing me handle the first card responsibly for a fairly short time period, they gave me a much better CL on a second card. Perhaps other people can comment on whether or not they've had similar experiences. It might be better to just apply for a second card, especially if you're going to take a hard pull anywyay.
Starting Score: ~500 (12/01/2008)