JP GMR 3 Port comp carbon

[Fingi]

For those of you running GMR 15s how the hell you get the carbon build up out of your comps?

 

I have no access to ultrasonic cleaners or the like and my comp is pinned. 

 

I took a scraper tool to mine but aborted after scratching the inside a bit. Its at its worst on the first chamber.

 

Any adverse effects on accuracy from scratching a 9mm break?

[Darqusoull13]

It eventually shoots out. I wouldn't worry about it until it looks like it might make a ring smaller than 9mm or so. If you really want it gone use a dental pick. Push and chip it out. 

There's chemical mixes posted around but honestly I hardly even clean my bolt anymore. JPs just run and run. 

[ericskennard]

Bore Tech has a product called C4 Carbon remover. Stuff some clean patches into the comp. Then saturate the patches with the C4. Let it sit over night. The C4 will remove or soften the carbon build up. Use some qtips and clean what came loose. If you have to, use the dental pick or scaler to remove what is left.

[MemphisMechanic]

What load are you shooting?

 

With a coated bullet and dirty powder, you get some serious buildup in the comp. it also occurs even with an FMJ due to the exposed lead on the bottom of the bullet.

 

With a plated bullet or a JHP? You’ll be shocked how much cleaner the gun runs overall. Both in the junk that isn’t building up in the upper and especially in the comp.

[mveto]

I always used Slip 2000 Carbon Killer on my comps, let it sit a bit and use a nylon bore brush and scrub it out, always works well for me.

[Neomet]

To really minimize the amount of buildup spray Dillon case lube in the comp as the last step of cleaning the gun.  It really helps keep crud from accumulating in the comp.  

 

[wgj3]

5 hours ago, MemphisMechanic said:

What load are you shooting?

 

With a coated bullet and dirty powder, you get some serious buildup in the comp. it also occurs even with an FMJ due to the exposed lead on the bottom of the bullet.

 

With a plated bullet or a JHP? You’ll be shocked how much cleaner the gun runs overall. Both in the junk that isn’t building up in the upper and especially in the comp.

 

This is most important detail. Depending on what projectiles you're running, that buildup may consist of different things. If "coated" bullets are used, lots of that buildup can actually be lead deposits too...

It will chip out.

[Bwillis]

Punch and hammer cleaned mine out, no change in accuracy. I know some people that use a dremel. 

[Old3GNR]

Punch and hammer works and  small engraver tool works as well.  Switch to JHP and the problem goes away.