I’m getting a build up in my barrel from the power belt bullets.
Any advice. Wonder if Ed’s Red would do it?

I use acetone and a steel brush.

I use MEK on my shotgun wad plastic.  But it's the same concept.  Just don't get it on anything you don't want chemically melted...

Is it for sure bonding to the barrel surface? It comes out as green stringy pieces out of my TC Encore when I swab.

It seems to be kind of melted specks in there. If I can find a nice brass or bronze bore brush that fits snug like a 12 gauge or 16, I think that will help with removal.

When I fire the first round, it leaves a residue where the bullet is seated. This makes seating the second shot higher in the barrel since the residual doesn't allow me to seat the projectile all the way down as far as the first round. This requires me to clean the gun about every second or third shot when I'm practicing.

A coke can aluminum cup under the power belt probably would keep it from melting

Uhhh... never heard of that one; not sure I understand. Please further explain? Thanx

If I remember a power belt has the plastic ring on the bottom hangs down to create a seal that expands to create a good gas seal.
This needs to be protected from the flame
On the bottom of a lead center fire rifle bullet often have a gas check to keep leading down

A cup that protects the plastic from the flame about the same size as the inside diameter as the power belt would push up inside the power belt and expand the belt but keep the heat off the plastic for a second. But forming a cup is not easy so a simple disk should work
I would cut a disk aluminum beer can so that it would need to pushed down the barrel on top of the powder then load the bullet and see if this helps with the melting plastic problem

Here is a paper punch for 1/2”
Link

There are many sizes available

Or you could glue it the base of the plastic.
I might give it a try. The second round would not seat quite as far down as the first. The third round would sit an inch or so off the powder because you couldn’t push it any further down.

Remington used to sell some cleaner that was supposed to be for removing plastic residue (and lead) from shotgun barrels.  Haven't looked for any for years.

I used to see kits for sale that were set up to cut round discs from soda cans and form them into gas checks.  Haven't looked for those for several years either.

Youtube video on making your own gas check



Gas check making tools/dies on e-bay.  Lots of different calibers.  Don't know if any of it would work for your needs.

https://www.ebay.com/sch/i.html?_from=R40&_trksid=p4432023.m570.l1313&_nkw=gas+check+maker&_sacat=0

The first inline i actually saw someone shooting at the range was being fed powerbelts. The guy told me it was his favorite deer dropper. It was a CVA (Optima, i think)

He was making egg sized groups with it at 100, but his rate of fire was very slow and methodical.

He'd shoot, remove the breech plug, wipe and grease it, douche the barrel with a wet mop,  run a bronze wire brush tip to remove the plastic several times, a cleaning patch, run a bore butter patch down the bore, reinstall the plug and reload. He said he liked to make every shot on a clean, cold bore. I think it was two 777 pellets behind 300 grain PBs.

Apparently the bronze bore brush dragged the plastic out in his routine.