"an adjustable/crescent wrench"-not recommend! If you do a search on this site you can find all kinds of ideas for removing a barrel the first time. I don't know what you have available to you "shop" wise, but I have made oak blocks, drilled to the diameter of the action, and clamp it in a bench vise. I prefer to hold the action, rather than the barrel, because the action is strait, whereas the barrel is tapered, and I get a better grip. I have found that "string line chalk" works as well as "rosin" to help with the grip. Some barrels come off fairly easy, others are more difficult and require more tactics, as can be seen by reading the experiences of the members here. It somewhat depends on your mechanical ability at this time. Take your time, and if you hit a snag, let us know and you will be helped!

Good Luck........Jim