I appreciate your suggestions. This is becoming one those obvious problems with a not so obvious solution

When I bought the IG-60 cassette a few years back, it came in a Shimano box with docs. This time, the HG-30 came in a plastic bag...actually 2 bags. A small bag held the 6th and 7th gears and the lockring, so I'd like to believe I got the right lock ring for this cassette. That was in a larger bag with the main cassette (gears 1-5 riveted together). I want to believe this was mfg'd by Shimano (lock ring says so), but the bag had no printing and I don't remember anything other than the no. of teeth stamped onto the cogs (one of the cogs may have had the CS-HG-30 model number stamped on it). I bought it thru Walmart and suspect this was a qty. buy from Shimano and was packaged this way to shave a few dollars off Walmart's cost.

I did compare the new lock ring with the one from the cassette I replaced (which never gave me any slip issues), and they look pretty much the same...maybe exactly. I could try using the old lock ring and see what happens, but I suspect that may not make a difference. I am going to go back over the whole hub/freehub/cassette/chain assembly (again!! and see if I can determine how well the chain is seating in 7th gear. I also want to figure out the source of the slight "wobble" I noticed and see if that might not be a/the main contributing cause.

Cheers...Steph