What a lot of people don't realize is that TC has 3 or 4 different size locking lug. The size is in the thickness. The ramp on the locking lug is a 3 degree slope. When T/C matches a barrel to a frame, they listen for the sound of the locking lugs snapping into place when the action is closed. If it is mushy, they check lug thickness and go one size down and try again.
Lug thickness difference is just a few .001" between all of the sizes. It isn't a whole lot. I have seen folks take a file or a stone and just start grinding away on the locking lugs without checking anything. I have checked guns that were filed like this and found only one of the locking lugs engaging. DANGEROUS.
I have a tube of Outers gun grease. It is BLACK. I dab some of that on top of the locking lugs and close the action. The grease should clean off the top (bevelled) surface of the locking lugs almost to the depth of the
"U" notch. (I have set the strike thru on to see how far it goes down my U.) After checking I see the strike thru is about mid way. This is probably the minimum you want to lock. I like mine to go deeper so imagine if the strike thru line is half way down the U, you want to go another 1/4 of the way so the upper 3/4 of the U is clean of grease.
You can stone, or hone, or file your locking lugs, but you must take care in keeping the bevel and you must also take care in keeping both of them the same. A few strokes with a good stone or diamond file can make a difference. Apply grease and retest often. A toothpick can easily respread grease already there.
If you go too far, your accuracy will go to lleh. If they don't lock enough, the action can open on firing.
If you do this test with the grease, please make sure you remove it when you are done. Gobs of yucky grease attracts dirt. Greasy dirt is similar to polishing compound. It will wear parts. I do put just a touch of grease on my locking lugs, but it is such a minute amount to keep any galling from occuring.
Good luck with the new barrel.
Steve