I have a factory Wilson 300 HAM’r pistol with an 8” barrel. It is 100% stock as it came out of the box.I have a can on it.

I am shooting 130 gr hot cors with nickel cases, Wilson factory ammo. The gun shoots great and has never jammed or given me any issues. I filled up a mag with shiny new ammo fresh out of the box, shot maybe ten times, and it looks like this. i have never noticed this on any other gun I have.

Running suppressed? My bet is yes, see that more when shooting with a suppresser.

Yes, since you are running a can the back pressure sends the carbon fouling back into the action. I bet your bolt and bc are heavily fouled as well.

Yep. Part of the deal. Add cleaning mags and unused ammo to your list.

I didn’t know it was that bad. How does this affect reliability?

I cannot speak for the 300 Ham'r specifically but the guys I train with easily go thru hundreds of rounds of 5.56 looking like yours and have no problems. You might want to ask the group if when running a can the rifle needs more or less lube.

Suppressor with lots of back pressure + short barrel = massive fouling in the action

With a 16" barrel it would probably take 30+ rounds to get that dirty. 30rds is the interval I give my suppressed guns a quick clean and lube.

In my experience, quiet can = lots of back pressure, not so quiet can = less back pressure

Suppressors are great on bolt guns, but can be a pain on semi-autos!!!

It’s normal…but a bleed off adjustable gas block can help. Superlative seems to be my current favorite.

Yes on the gas block. I’ve seen a Raptor charging handle with a gas release option but have not tried one yet.

This puppy gets dirty real quick. 10.5” in .300 blk

Here's the nickel boron BCG out of a 16.2" 300 HAM'R after 30-40 rounds. This is about as dirty as I like it to get, still fairly easy to clean up.

Bill, are you just using the WC branded cleaning and lube products?

16" .308 Win, 155 TMK, well over 44.0 gr of powder. It will foul the round in the mag that bad in under 10 shots.

Of course, higher powder charge, more gas, more fouling.

Thanks for the replies. Short barrel and suppressor the fouling makes sense. I just haven't seen it before. My 16" 300 HAM'r with the same can doesn't foul anything like this.

I may just buy a longer barrel for it. As much as I try I just don't like the feel of shooting with a pistol brace. Either that or buy a stamp and put a stock on it.

For the most part yes, but I'm frequently testing new products that come to market too. This BCG was lubed with our grease which I typically use in the summer and switch to Universal in the winter. For BCGs I like lubes that stay where you put them and I only lube areas that contact.