tons of junk coming from suppressor into pistol action

[rtv900]

so I've just tried out my form one a couple times now on my 9mm, and now that I got a booster it cycles well.
That is, until I get a few clips into it then all kinds of debris starts coming back into the action and either jamming it up or just blasting me in the face with fine particles.
Once a chunk of something actually got in front of the firing pin and prevented the pin from striking the primer enough to fire.
Some chunks are downright big.
This is not a baffle strike issue, nothing is hitting at all.

My 22 never has junk coming back into the action and I thought if anything the 9mm would be far cleaner, but it's 10x's dirtier.
I only got maybe 60 rounds in before I stopped and I swear I could pour debris out the suppressor/booster.

Is this just what is to be expected? I've never shot a 9mm suppressed before so I don't know if I'm doing something wrong or just don't know what it's like in reality.

[T-Rex]

Post some pics of internals, so we can see what's going on inside.
Ammunition specs?
What pistols and spring weight?

[rtv900]

it's an M&P 9mm 2.0
I was using winchester 115 grain ammo, has always been fine

I got the booster from AJ guns, I am using the booster spring that came in it although a lighter one was supplied. But the heavier one cycled fine so I figured why mess with it.
The gun is stock.

I could get some pics once I get home, but there's not much to see. Just look likes a normal baffle with debris like sand and some big pieces too before I dumped them out. After dumping it out just blackened steel.

[alordnapa]

Increased back-pressure is an inescapable side effect of adding a suppressor ( There are some manufacturers that say otherwise, but I think they are Commies...) Effectively, your action is opening too soon, and the gas pressure is causing that mess flying back into your face and dirtying up your gun. You can try a heavier recoil spring or a lighter load. If you have had no dirty block-back from your .22, let me just be the first to say Mazeltov! I can't fire any .22 pistol for a day without coming home looking like a chimney sweep! ( Of course, I get out to the desert so infrequently these days that I tend to fire a bucket full of bulk ammo when I get there...Anything worth shooting once is worth shooting 500 times, I say!)

[rtv900]

ok, so I should try a heavier spring then.
man I thought the one that came in it was heavy already but I have no reference

yeah the gun got filthy as hell
basically it got dirtier than firing 5x's the rounds out of a non suppressed gun

[T-Rex]

The spring in your gun, not the booster. The booster spring works in conjunction w/ the suppressor weight. The pistol's recoil spring will delay the action's unlock time.

I was interested in pics for, above all things, an idea of baffle geometry and their direct impact w/ back pressure.

[rtv900]

oh the gun, ok I misunderstood that

yeah I'll get a pic tonight provided I think of it

[John A.]

Try more suppressor appropriate ammunition.

Something maybe 147 gr or perhaps 158 gr.

For starters, 115's have more powder and higher velocities than subsonic ammo which equals to more crap coming back at you too. Plus, I don't know what kind of bullets specifically that your Winchester ammunition is using either.

Plus, I'm not a huge fan of Winchester ammunition in the first place.

To me personally, I think your bullet choice is more to blame for your woes than anything else.

[rtv900]

I do have some 147 grain subsonic on order, but my timing in finishing my can was as bad as possible and landed right after the media fueled panic of covid, so I have a feeling I'll be waiting 2 or 3 months until it arrives.

The winchester I was using is full jacketed, but anyway yes they are high velocity.

Otherwise the suppressor works pretty well, the sonic crack is by far the loudest noise and other than that it is fine to shoot without ear protection.
The crack is kind of irritating though.
I think once I get the subsonic it should be nice.
The sand blast to the face is the worst part, I can deal with the cycling issues since it cycles 95% of the time.