I'm trying to kill the coverstock on a few older balls so I can use them on the BURN.

I'm looking to completely kill them and don't care if they get ruined.

Any tips?

What polishes have slip agents?

The 3 current skip agent polishes of which I am aware are
Valentino's UFO,
Powerhouse's Delayed Reaction, and
Brunswick's (Neo-Tac's) Control-It.

Of the three I prefer UFO because it's easier to remove with a light sanding; as light as a 4000 grit pad can remove it..
The other two need a rougher grit sanding to remove it; 500 - 1000 grit.

Also you can do one of the old fashioned ways: use a car polish with silicone wax in it; not sure if this can ever be removed. Least, I have not tried to do so.

If you really want to kill it, first sand it to 4000 grit; then use a White Trizact pad which is in the neighborhood of 6 -8000 grit, before applying any of these polishes.

And use a lot of polish and burn it in until the polishing rag gets fairly warm.

Shine the crap out of it on the spinner, then put it in the Luster King machine that some bowling centers still have.  They use a solid compound that will usually clog the pores nicely.

Turtle Wax used to work, too.

Take it to 4000, then polish it hard with Turtle Wax.  --  JohnP

Sanding the ball up to 4000 grit to start, then I prefer using 3m finesse it. Apply with a rag then I use my bare hands to help create extra friction and burn the polish in. It works quickly and makes the ball extremely shinny. You can repeat the polish process if needed.

Take it to 4000grit polish it then hit it with some rain x.

4000 to start and then the Luster King will work.  Never thought about rain x but then that stuff actually fills the pores when used on glass to create a skid surface for water.  That may be worth a shot.

4000 Grit and then two coats of our polish UFO, which has a slip agent in it.

No reason to ruin a coverstock to achieve a finish/reaction

I think you have to go this route. You need something with a slip agent in it. I have tried alot of methods. I also have had some success with using Turtle Wax.

But in reality, I usually have to go to weaker coverstock, Urethane and Plastic. Because if you really mean "BURN", plastic is your best option.