Hello, new to the forum and to auto loading shotguns, so forgive if this is a dumb question, but here goes. I bought an 1100 LT 20 ga at an estate auction, so i know no history at all. It has synthetic stock, 26", 2 3/4 only, ser# R25xxxxK. My question is - with the action open (unloaded), if I tip the barrel up and down floor to ceiling, I can hear the gas rings sliding on the tube. Is that normal/safe? I replaced the O ring with correct part from Cabella's because the one on it was worn, but the two metal rings will slide up and down. Any info will be appreciated. Otherwise the gun looks to be in good condition. Thanks.

Perfectly normal. It is advisable to place the splits in the rings at 180 degrees.