Pitting in the chamber, did I do it?

[mike_srt4]

Video of the bore camera footage.


This is my PRS barrel it’s a Bartlein and I’m sure it’s something I did and not the barrel. I’m looking to isolate so I don’t do it again. Barrel has about 1k rounds on it shot a few matches. For the most part I clean after shooting. Recently switched to Thoro clean. Prior to was using Iosso Triple action and bore paste, accompanied with wipe out patch out. I don’t think it’s the Thoro clean, but it is a newer product. Once I’m done cleaning I run a patch of alcohol followed by a few dry patches.

If I only fire a few rounds 30 or less I won’t clean, or if I’m using it for hunting predators on my property I’ll leave it fouled only taken a shot once a week or two weeks.

Im wondering if my last hunt caused it. It was about 20degrees out and I was out with my rifle for about 2hours. I brought the rifle and all my gear back into my 68 degree house. I am thinking condensation in the barrel then sitting for a week and a half may be the culprit.
I discovered after going to load a round and take a shot. I had trouble closing the bolt but then it closed. After firing the round I had a super sticky bolt. I took a video of the bore camera images. Did some before and after a very light cleaning. Pitting looked way worse prior to cleaning. I thought a chunk was missing.
I reached out to gun smith. He asked how the brass looked and it was fine. So I’m going to shoot a few rounds to see how it is.

Any feedback is greatly appreciated!

 

[Aftermath]

I learned a lesson a long time ago that corrosion can happen amazingly fast. There is an often posted study of corrosion inhibitors and the WD40 Specialist stuff rated real high as did Hornady OneShot. You won't have to search this site much to find that study posted.

The good thing is, if it shoots good, just keep shooting it. Just be sure to take every opportunity to prevent corrosion from this point forward. That spot will want to corrode again more readily.

My GUESS is that the condensation episode is what did that. If you are in that situation again, be sure to open or pull the bolt as you allow the rifle to come up to room temperature. Leave it muzzle up so that any condensate will run out the action side. Even better if you can get it in circulating air...just a little movement makes a HUGE difference. Once it is warm, clean it and oil it.

In the safe, leave the bolts open or removed. I prefer just open so I don't have to fish for the bolt...I can still sort of grab and go. I use these Bullfrog Emitter Shield. They are supposed to be good for a year. I use them in my safes for 6 months and then they get rotated to the tool boxes. I also have a dehumidifier rod thing that mainly just generates some heat.

 

[XLR308]

I have used mostly CMV barrels in central and south Texas hunting in high humidity and rained on frequently and have never seen anything like that happen even with sweat from handling.
The snake oil I have allways used is FP10 both internal and externally but I'm sure there are better out there just a creature of habit.
For a SS barrel that would look to be more like a chemical reaction to me but just a guess.

 

[mike_srt4]

I learned a lesson a long time ago that corrosion can happen amazingly fast. There is an often posted study of corrosion inhibitors and the WD40 Specialist stuff rated real high as did Hornady OneShot. You won't have to search this site much to find that study posted.

The good thing is, if it shoots good, just keep shooting it. Just be sure to take every opportunity to prevent corrosion from this point forward. That spot will want to corrode again more readily.

My GUESS is that the condensation episode is what did that. If you are in that situation again, be sure to open or pull the bolt as you allow the rifle to come up to room temperature. Leave it muzzle up so that any condensate will run out the action side. Even better if you can get it in circulating air...just a little movement makes a HUGE difference. Once it is warm, clean it and oil it.

In the safe, leave the bolts open or removed. I prefer just open so I don't have to fish for the bolt...I can still sort of grab and go. I use these Bullfrog Emitter Shield. They are supposed to be good for a year. I use them in my safes for 6 months and then they get rotated to the tool boxes. I also have a dehumidifier rod thing that mainly just generates some heat.

I have a barrel cooler I’ll be sure the put that in and let it run. Going on a cold hunt to tomorrow. I had the bolt closed when I got inside.

 

[Baron23]

Do you use a golden rod or similar in your daft to reduce humidity and any humidity effects on your metal.

They are inexpensive and even my were SBE II has done fine and it’s not really dried and cleaned and a long day of goose hunting. No pitting Even though the gun often went into the safe dam at best

I attribute this to the safe heater.

https://www.amazon.com/MAXSafes-GoldenRod-Safe-Dehumidifier-Power/dp/B0BM9NQPW4/ref=asc_df_B0BM9NQPW4?mcid=e48fb5c01df838d6bdae698fbaad9c76&hvocijid=5328505631540422051-B0BM9NQPW4-&hvexpln=73&tag=hyprod-20&linkCode=df0&hvadid=721245378154&hvpos=&hvnetw=g&hvrand=5328505631540422051&hvpone=&hvptwo=&hvqmt=&hvdev=m&hvdvcmdl=&hvlocint=&hvlocphy=1018700&hvtargid=pla-2281435179778&psc=1

 

[Robert4]

To me, that looks like a chunk of unburned powder that was mashed by a round being fired after it was left there by the previous round. My shooting buddy had something very similar happen. It was fairly difficult to remove.

 

[mike_srt4]

I learned a lesson a long time ago that corrosion can happen amazingly fast. There is an often posted study of corrosion inhibitors and the WD40 Specialist stuff rated real high as did Hornady OneShot. You won't have to search this site much to find that study posted.

The good thing is, if it shoots good, just keep shooting it. Just be sure to take every opportunity to prevent corrosion from this point forward. That spot will want to corrode again more readily.

My GUESS is that the condensation episode is what did that. If you are in that situation again, be sure to open or pull the bolt as you allow the rifle to come up to room temperature. Leave it muzzle up so that any condensate will run out the action side. Even better if you can get it in circulating air...just a little movement makes a HUGE difference. Once it is warm, clean it and oil it.

In the safe, leave the bolts open or removed. I prefer just open so I don't have to fish for the bolt...I can still sort of grab and go. I use these Bullfrog Emitter Shield. They are supposed to be good for a year. I use them in my safes for 6 months and then they get rotated to the tool boxes. I also have a dehumidifier rod thing that mainly just generates some heat.

I have a barrel cooler I’ll be sure the put that in and let it run. Going on a cold hunt to tomorrow. I had the bolt closed when I got inside.

Do you use a golden rod or similar in your daft to reduce humidity and any humidity effects on your metal.

They are inexpensive and even my were SBE II has done fine and it’s not really dried and cleaned and a long day of goose hunting. No pitting Even though the gun often went into the safe dam at best

I attribute this to the safe heater.

View attachment 8601185

https://www.amazon.com/MAXSafes-GoldenRod-Safe-Dehumidifier-Power/dp/B0BM9NQPW4/ref=asc_df_B0BM9NQPW4?mcid=e48fb5c01df838d6bdae698fbaad9c76&hvocijid=5328505631540422051-B0BM9NQPW4-&hvexpln=73&tag=hyprod-20&linkCode=df0&hvadid=721245378154&hvpos=&hvnetw=g&hvrand=5328505631540422051&hvpone=&hvptwo=&hvqmt=&hvdev=m&hvdvcmdl=&hvlocint=&hvlocphy=1018700&hvtargid=pla-2281435179778&psc=1

Thanks for sharing. My rifle goes on a wall in a gun room when done it stays same humidity level as the rest of the house which in the winter is very dry. I don’t like to store my rifles vertically however after a hunt if it makes send I can bipod them with no bag. Also I wonder does leaving the suppressor on trap moisture for a longer period? Maybe in the baffles where air flow is harder to get to?

 

[mike_srt4]

I found the piece of brass that was shot right after the hard bolt close. Retrospectively seemed like there was a physical piece of debris in the chamber. I thought maybe the damaged steel in the chamber flaked a piece off and that’s what the blockage was.
The damaged shoulder appears to line up with the chamber.
I fired one shot more shot before discovering the chamber damage that brass didn’t have anything wrong with it. After I saw the damage I cleaned lightly with patch out to ensure physical debris was removed. Those 4 pieces of brass all looked fine. There was a piece of debris caught in the gap of my hellfire adapter roughly the size of a kernel of powder that I found after removing my Maverick. Thinking that may have been pushed through on one of the cleaning patches. Didn’t look like a kernel more like a chunk of carbon.

Brass is Lapua 6BR, 6 BR chamber.

 

[Mordamer]

Likely just a piece of carbon in your chamber that fell down the bore from the suppressor. It's very common. I don't think it's corrosion pitting. It is very hard to tell the difference between something raised and something below the surface with a borescope.

Your brass tells the story. It's appears to be a raised feature indenting the brass and not pitting. Deep pitting allows the brass to flow in and makes for hard extraction, but not hard bolt close.

Get it out and you'll be back in business.

 

[Rookie]

The vid appears to show the area of concern is in a rifled area not the chamber. Am I missing something?

 

[mike_srt4]

The vid appears to show the area of concern is in a rifled area not the chamber. Am I missing something?

It’s in the chamber right before the carbon ring typically forms.

 

[Baron23]

Bore Tech carbon remover and a brush would prob help.

Do you have a good carbon remover solvent already.

And here’s hoping everybody is right (and prob are) that it’s just carbon in you chamber.

Cheers

 

[mike_srt4]

Bore Tech carbon remover and a brush would prob help.

Do you have a good carbon remover solvent already.

And here’s hoping everybody is right (and prob are) that it’s just carbon in you chamber.

Cheers

I’ll have Iosso triple action and paste. Also have Bortech carbon remover, patch out + accelerator, and the new Thoro clean. Probably stay away from that for now. I haven’t scrubbed the chamber area yet, only Iosso nylon brush with a patch on it. When I ran the patch out through I had a PMA bore guide in so I was working past the trouble area.
Having issue with depth perception makes sense on the camera.
I’ll give the troubled area a little work with Tripple action first then step up from there until clean if cleanable.

 

[mike_srt4]

Likely just a piece of carbon in your chamber that fell down the bore from the suppressor. It's very common. I don't think it's corrosion pitting. It is very hard to tell the difference between something raised and something below the surface with a borescope.

Your brass tells the story. It's appears to be a raised feature indenting the brass and not pitting. Deep pitting allows the brass to flow in and makes for hard extraction, but not hard bolt close.

Get it out and you'll be back in business.

Thanks again, for in there with a nylon brush and it’s 100% gone.
Glad it wasn’t anything else!