Suppressor causing chamber condensation

[Foster_65]

I know this sounds odd and I can’t find much on this subject other than a guy on snipers hide that had the exact same issue. I have a 6.5cm that was a great shooter pre suppressed. I cut the barrel to 20 and now I’ve been shooting it and getting weird pressure spikes. Thought maybe I needed to change loads but if I shoot about 3-4 no problem. Accuracy is still not quite as good as pre barrel cut that that may be fine tuning the load a bit. However when I get the pressure signs I notice as soon as I take the round out of the chamber there is visual condensation on the brass. There is gas that comes out the chamber end of the gun for a bit but I assumed that was normal with a suppressor. It has been warm and humid here but it’s strange that it only happens after about 5 rounds. Im new tot he suppressor game so Im just wondering if anyone has experienced this and why it only happens with a suppressor. I’ve ever had this happen over thousands of rounds unsuppressed. What can be done to mitigate these issues.

 

[Foster_65]

Since nobody responded I thought I’d share some info I tested today. Shot this morning with a 5-10 mph wind at 12:00. I shot three rounds at a time and then I would flip the gun around so the gasses/smoke wouldn’t exit the chamber. This definitely helped with the pressure spikes and condensation issue. Barrel still shoots like crap after being cut and threaded so I’m not sure what to think about that. Has anyone had a load go way out after a barrel cut? Went from a 1 moa gun to 3 moa gun overnight. Any thoughts? Thought maybe it was just the gas/condensation issue

 

[HandgunHTR]

You will have to work up a new load once you chop it. I have had a couple that still shot about the same, but most of them, I had to tweak a bit before I found a new load that worked. Adding a suppressor is putting a 9-15oz weight at the end of the barrel. It will change the harmonics quite a bit.

Part of the fun for me, I guess.

 

[LaHunter]

Sounds like you have something else going on to cause condensation in you chamber / on the spent brass.
Are you keeping your ammo cool prior to shooting in warm / high humidity conditions? If so, this could be the cause of your condensation if the ammo is cool enough and the air has enough moisture / humidity.
Where is your ammo prior to loading / shooting?

For water vapor to condense it needs to contact something to cool it enough to make it change from vapor to liquid. Think of a cold beer can on a hot / humid day. It immediately starts to get condensation on it from the moisture in the air.
A warm rifle barrel / action / spent brass would not be getting condensation on them.

Are you sure what you are seeing is not left over oil in your chamber?

What rifle?

What suppressor are you using?

 

[Foster_65]

I’m using an Enticer LTi. Rifle is a howa 6.5 cm. Load is 41 gr h4350 pushing a 140 eldm. Gun shot great pre cut with and without the can. my reloads are stored in my basement then about 30 min drive to range then shoot. The odd thing is that the first 5 or so don’t have this problem, then the rest will. Say maybe 15. I took the rifle home and scoped the chamber area and it was very dirty. Soot/carbon. I will say that the last batch of sizing when tumbling I noticed my media was pretty gross so I have since changed that. I can’t figure it out either but there seems to be a correlation with smoke/gas blowing back out of my chamber after shooting. I did read of a guy on snipers hide that had this exact problem. He had pictures and everything but there was no conclusion. There definitely is condensation, could it be a mixture of hot air trying to get in while the gas is coming out of the chamber? When the brass comes out it feels almost sticky but it didn’t go in like that.

 

[Foster_65]

It’s also interesting that I run this can on a 6arc and my chamber isn’t dirty like this and all. I have some other cans I could put on and try but I’m not sure that’s the culprit but maybe.

 

[E.Shell]

I've had dozens of shooters bring suppressed rifles to the range at all times of year without experiencing issues with their rifles. As others have said above, something else is going on and whatever the OP is experiencing isn't suppressor-induces condensation.

 

[Fireflyfishing]

Are these factory loads?

 

[Foster_65]

No these are hand loads.

 

[Bluefish]

Don’t have an answer, but combustion does produce water. I could see that you are trapping combustion gasses and they have moisture. Then it’s not hot enough to keep it vapor. Like what happens in car exhaust when you start up. Exhaust gas has water in it, but the exhaust is cold so it doesn’t stay vapor and you get water in the exhaust until it warms up.

 

[Shortschaf]

Clean your suppressor and barrel and see what happens

 

[Conrad]

This is an absolutely a thing and I know I posted on the hide about it and came back with a follow up confirmation post. I commend you on your wind observation as I noted the same thing. When it is humid with a 12 o clock wind and you see smoke get pushed from suppressor and back out the chamber you are going to have problems. It’s almost like smoking a piece of brass with a candle as far as how some carbon is deposited in the chamber. I typically see crap on the body of the brass. Wiping out the chamber allows the next shots to be extracted per normal. It can really jack with a shooting session when it happens. I have to assume a lot of these guys in the west with low humidity will never see it.

 

[Foster_65]

I have been very purposeful on the range I use or where I set up to insure wind is at my back preferably. You are correct on high humidity and I was able to replicate. Like you, I am diligent to keep my chamber clean and it helped a lot if I can’t get the wind the way I want it. Thanks for the follow up post confirming I’m not crazy.

 

[Conrad]

You’re not crazy. My above post was somewhat descriptive/qualitative but to describe the science more…it’s simply condensation as a result of super heated air in the suppressor being cooled by the 12 o clock wind. With high temps and high humidity the dew point can only be 5 degrees lower. A little cooling and Condensation occurs and the 12 o clock wind carries water vapor into our chamber. I’d imagine the carbon I see on brass could be a bit from the smoke but it may also already be there we just never collect it on the brass until we get the over pressure event from the water. Hope that makes sense!

My 100 yd range down the road where I do load development often has a 12 o clock wind so I’ve seen this multiple times. Central TX here, plenty of humidity in spring/fall.

 

[Lawnboi]

Iv seen the same exact thing happen.

Especially during matches, anymore first thing that goes in the chamber after a stage is the fan. Same with at the range if conditions dictate it.

I have more of an issue during spring months where you’re shooting in the 50s with high humidity and like you it seems to be exacerbated by a headwind.

A chamber fan pretty much removes this during shooting sessions.

Seems more apparent in cases that heat the barrel more.