Most Hardware stores will probably sell the 61 o-ring. They are by far the easiet fix for the loose barrel issue and one should last for years altho I suggest buying several so you do have spares just in case. Myself I do not like using Locktite on any firearm for any reason. Makes a darn mess which can be a bugbear to clean off of some designs. Besides the O-ring will be much cheaper anyways as well.