I had the chokes opened to .004 and .008 on my 20ga 26" repro. It is my primary grouse gun. Prior to the start of hunting season I'll put close to a 1000 rounds through it. I have never had an issue cleaning or with plastic buildup. In my view the powder used is much more prone to cleaning issues. I have never regretted opening the chokes.

The problem with plastic in a muzzle loader is black powder will melt the plastic in the barrel.

I have opened the chokes on two Parkers and have nightmare's over it. At one point I thought IC was the best of all worlds and opened up the left barrel to match the right on a GH I used for everything. Now I prefer about .015 constriction, light modified, and .025 an improved modified. I have a VH with 26" barrels choked like that. The other set of barrels are 30" with .030 and .042.
The other Parker opened up was a 32" VH choked full and fuller. 3" chambers and IC both barrels to shoot steel through. I want to throw up every time I think about that.

Harry

Thanks for the experience-based info on plastic fouling in smooth bores. I'd never seen it but you guys shoot a lot more than I do. I am going to have to do something about that.

I shoot 3-4 rounds of skeet per week with my SSS. The thing is you can't see the plastic build up when looking down the barrels. However when I apply some solvent in the barrels it is amazing how the plastic rolls up when I send a jag down the barrels.

After discovering this I scrub the barrels on all my guns more frequently during shooting seasons.

I found that the plastic buildup in my 20 gauge Repro skeet gun really played havoc with my patterns and might possibly cause excessive pressure. I was amazed at the solvent-softened gummy buildup that I removed from the barrels.






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I am no expert or professional in ammunition construction.

But from a purely observational/experience standpoint, I've noticed these factors effect plastic fouling buildup.

1) Gun cleaning. If a gun is not cleaned throughly after each use, fouling hardens and layers up.
2) Ammunition choice. Import stuff is a cypher as to powder and wad quality.
3) Handloaded ammo powder choice. Powders like Red Dot foul more and create more fouling/drag.
4) Handload wad choice. Known quality wads like Claybuster are made with specially formulated plastic and foul less. Imports? They often foul more.
5) Primer choice. Federal or CCI Magnum primers help to more fully burn heavy fouling powders, leave less residue and thus less drag on subsequent wads/shots fired.

These are my observations only. See your ammunition professional for details. Tom Armbrust is one.

I use claybuster wads.

I had an issue with plastic buildup one time. It was with a well regarded low pressure factory load.

I use claybuster wads for everything and have never had an issue with plastic buildup in any of the guns I load for, chrome lined or not.

I have been using Gunzilla to clean shotgun bores for about 10 years. First saw it at the Grand American Tournament and while being very effective on plastic wad residue it is also much safer to use than some other solvents. Like some have mentioned, I didn't think I was getting wad buildup until I cleaned a bore or two with something like this that is very effective. I clean the bores of every shotgun I shoot every day after a hunt or trip to the range. Didn't always do this but had the chambers rust in a nice M21 Winchester because I was lazy. One of those things that make you sick when it was so preventable and I vowed it would never happen again.

I opened up the chokes on one of my Repros. No regrets.
I also clean my guns as soon as I get home. No issues with fouling