Here's a tutorial on a nub I think I invented.
It was inspired by the MASADA arm, and before any of you say I'm copying him and whatever, I asked him to make this thread and he's chill with it.
Acquire an Action Army chamber or really any hop chamber, but you may have to figure things out yourself.
Acquire aluminum tape and JB Weld Steel Stik epoxy putty.
I have tried at least 10 different materials, and this exact one is the only one that worked out well.
Put 2 bands of aluminum tape on your hop arm in these exact places, just barely covering the spring hole, and about 2.5mm from the nub groove.
You want your arm to be tight enough that it doesn't wobble at all, but you want your spring to be able to push it back up so you can still remove hop without taking it apart.
Lightly grease the green areas with some sort of grease.
I used TechT gun grease, but you could probably do exactly as well with some chapstick or something.
Wrap a perfectly round rod with some sort of tape, but you need to put some Scotch tape on the outside.
You would be preferably using a Delrin or Teflon rod with the exact OD as the ID of your chamber, but tape and a rod work perfectly fine.
Insert it into the chamber where the bucking would go.
It should be as tight as possible, with no wrinkles or imperfections visible through the hop window.
Slice a small section off of the epoxy putty and mix it until you can't see a single light or dark streak, then mash it carefully into the hop window, making sure to poke the putty into the corners leaving as few air pockets as possible.
Save a little ball of the putty.
Squish down the arm so that it is roughly level.
This will ensure that you can have zero hop and a ton of hop, instead of just one.
Pry out the arm after about 10 minutes, or until the little ball of putty is pretty hard but not completely.
Then once you have it pried out, trim the excess so it looks like this.
You want the actual arm to be exposed like so, and you want the entire thing to be tapered inwards so you have full control of your hop setting.
Let cure overnight, and add new aluminum tape if necessary.
The aluminum tape is even better than most TDCs as it doesn't require irreversible modification, and keeps the arm/nub more stable that most TDCs.
The only disadvantage is that you still have to adjust through your magwell, but once you adjust your hop it will stay put until your contact patch wears out.
I encourage you to try this for yourself as it's almost free, and you can make a shit ton of nubs if you grease everything, that way you can pop it off.
Another thing I recommend to do if you ever want to remove this nub is to soak it in acetone for a couple hours and it will come off with ease.
You'll have to make a new one though, it will probably be ruined.