Hello. I have a P226 Combat from 2012, non-threaded. The barrel has chrome flaking at the throat. I got the pistol used (won it on one of Q's generous pistol giveaway contests), so I have no idea how many rounds were fired. The pistol looks nearly new though. I fired it a few times but I'd be surprised if I put 500 rounds through it in the time I've owned it.

I borescoped it and the carbon buildup copper fouling was horrendous I spent a few hours last night cleaning it and I just have some copper left near the chamber to get out. When I run a patch and jag through the bore I can feel the roughness of the chrome flaking catching the fibers. I still have some more soaking and scrubbing to do, but here's what I'm seeing.





Accuracy is pretty good for this pistol. Given this deterioration, I'm concerned it will foul quickly. Any idea how much life I have left in this barrel?

I see Sig has replacement MK25 barrels for $175 which are identical to this barrel. Should I get another chrome lined barrel or should I get a standard barrel? I'm thinking of perhaps getting a BarSto threaded barrel instead since this one is a standard? Maybe have the BarSto nitrided after fitting.

Tony.

This message has been edited. Last edited by: benny6,

How does it shoot? If it still holds accuracy and fully functions, I might keep shooting it. Probably will accumulate copper fouling more than a new barrel would, though.

I sent the pictures to Sig to get their opinion and they offered me a 10% discount on a new barrel, so I took them up on it. Should have a new barrel in a couple of days. This is my primary home defense weapon, so I'd rather just fix it.

I'll throw the old barrel in the parts box as a backup. After about 4 hours of cleaning and soaking, I finally got that last bit of copper out of the barrel.



I'm going shooting tomorrow and I'll inspect it after the range trip to see how bad it fouls up.

Tony.

Those are some great images you posted, how about filling us in on the details of your bore scope. I've been considering getting one to check the forcing cones on my shotguns because if the plastic residue from the wads gets out of hand it can be areal bitch to clean up.

quote:

Originally posted by Scooter123:
Those are some great images you posted, how about filling us in on the details of your bore scope. I've been considering getting one to check the forcing cones on my shotguns because if the plastic residue from the wads gets out of hand it can be areal bitch to clean up.

Teslong USB borescope:
https://www.amazon.com/dp/B07T...1f-a281-df67fc737124

As a gun builder, I use this scope A LOT! I inspect fresh cut chambers after polishing. Here's one from last week.



Tony.

Any idea who did the plating? Did SIG farm it out?

Borescopes have a role for sure, but people need to understand a very simple truth:

If it shoots well, it doesn’t matter how bad it looks

If it shoots bad, it doesn’t matter how good it looks

In a service type pistol that has say an accuracy standard of 4” or less groups at 25 yards as an example, as long as it is maintaining that standard, keep running as is.

quote:

Originally posted by benny6:
Teslong USB borescope:
https://www.amazon.com/dp/B07T...1f-a281-df67fc737124

A second for this, these are cheap for what you get. Mine has been incredibly helpful. Pro tip: Fiddle with the distance you've got the mirror threaded in or out to focus. There were no instructions with mine.

quote:

Originally posted by captain127:
Borescopes have a role for sure, but people need to understand a very simple truth...

I used mine to fix a misaligned gas block on an AR and again to take a look at another that wouldn't cycle. I know some people like to keep a close eye on the bore, but there's other legit uses.

quote:

Originally posted by parabellum:
Any idea who did the plating? Did SIG farm it out?

I have no idea who did or now does, the plating. I didn't even know Sig did chrome lining on any pistols until I owned this pistol.

Tony.

So I took the pistol shooting on Monday and fired about 50 rounds through it. Here are images after I did a few passes with patches and a brush.

Here's an area with no pitting at the throat after 50 rounds and a quick clean.


Area with pitting.


I got my new barrel today and got some images of these new production run MK25 barrels.
This area has a "frosty" look to it.


This area does not.


Old vs new. Note the marking changes since 2012.




The pistol is back in service.


I'll take some borescope images after my next range trip.

Tony.

I could not own a bore scope. I am not truly OCD but I am damn near OCD adjacent and I keep my guns well cared for and having a scope for the bore well…….I’d over clean no doubt. Ignorance is truly bliss sometimes.

I have one for my work made in Germany. It seems it can't focus that close for a horizontal shot but does pretty good looking down the barrel... dern...now I got another tool for my hobby.

Now, I have to say in my opinion chrome plating the inside of a barrel seems kind of no longer needed these days with either a military weapon or a civilian one in the hands of a true gun lover.... seems to me like the original plating like this was for commie guns shooting the corrosive primer ammo and issued to troops that were not going to be very diligent in maintaining their weapons for the simple reason they were expendable anyway... both weapons and troops.....my father was there and they stacked 'em like cord wood... rifles and the frozen bodies.

Well, just for documentation's sake, I fired 100 rounds at the range today and borescoped the barrel before any cleaning was done. Here's what it looked like before any cleaning.



I then ran a patch of BoreTech eliminator through it and ran a nylon brush soaked with eliminator 15 times through the bore. I then ran a dry patch and scoped it again.



Since all that was left was mostly carbon, I switched to BoretTech carbon cleaner and ran a brush 50 times and cleaned again. I did this about 4 times for a total of probably 200 passes of the nylon brush through the bore and I got the barrel as clean as it was before any ammo was run through it.



I used a total of 15 patches and the BoreTech products.





Hope this is informative to anyone reading.

Tony.

quote:

Originally posted by cslinger:
I could not own a bore scope. I am not truly OCD but I am damn near OCD adjacent and I keep my guns well cared for and having a scope for the bore well…….I’d over clean no doubt. Ignorance is truly bliss sometimes.

You and me both! Just reading this post is starting to get me bothered about the condition of my barrels !

Thanks for sharing, though, Benny...very informative and it's cool to see how clean you were able to get it using traditional methods.

A few years ago on the web, I saw an interview with Frank Green of Bartlein barrels. Bartein bought a bunch of 308 chrome lined rifle barrels from competitors, and performed longevity tests on them. Frank stated the chrome-lining's longevity varied dramatically from one brand to the next. Some held up pretty well. Others began cracking and flaking after a couple hundred rounds. When the flakes broke off, accuracy deteriorated substantially. Frank said this is a prime reason why Bartlein doesn't chrome line their barrels.

I clean my barrels regularly. For rifles this is essentially after every day. For pistols I might go every other day, if the round count was minimal. I use patches with mild cleaners, with an occasional brush when I feel fouling is really bad. But my barrels aren't spotless after cleaning. I don't remove all the carbon fouling -- I don't clean down to the raw metal.

I have experienced carbon rings in 2 different rifle barrels. Both times were at matches, and my accuracy suffered. I'm now more cognizant of how a carbon ring feels while running patches down the bore. When I feel one, additional cleaning occurs to remove it.

Many moons ago I shot pistols quite a bit. Some of my best bullseye results were with heavily fouled barrels which deserved some scrubbing.

I had my 'smith borescope the first 6.5 Creedmoor rifle barrel I shot out. He said the throat was nasty -- looked like alligator skin, with lands missing for at least an inch. The barrel lost some velocity, producing some low impacts and more horizontal dispersion than expected for targets beyond 600 yards at a match. Nevertheless, the barrel was still sub-MOA at 100 yards.

*****
I believe barrels should be cleaned regularly. I don't feel they should be spotless in order to perform their best. I believe down-range targets tell the tale of when a barrel should be retired to being a tomato stake.

I put this stainless P226 together to replicate the long out of production SIG factory offerings (the USPSA models) they made for a short time around 2010.
Two USPSA variants were made back then and I greatly prefer the stainless frame model over the anodized aluminum frame model.
I tried for a very long time to locate and purchase one stainless frame USPSA model with no success.
This originally was a .40 caliber pistol, I replaced the .40/.357SIG natural stainless slide with a 9mm version finished in Nitron.
Just because I could, I added the chrome lined barrel. I was surprised how rough the hard chrome finish was on a brand new replacement barrel.
I shot several hundred rounds of jacketed ammo for barrel break-in before switching to cast lead projectiles for IPSC competitions.
Surprisingly, it does not appear to lead the bore. I generally shoot at least 500 rounds of cast lead ammo before cleaning.
I also do not clean the bore aggressively.

Here are several photos of a genuine stainless frame USPSA model graciously provided by a Forum member.
Note that the USPSA models did not ship with chrome lined barrels to the best of my knowledge.

Right by cee_Kamp 32ACP, on Flickr

Top by cee_Kamp 32ACP, on Flickr

Here are a few photos of the stainless P 226 that I assembled.
This has the new production chrome lined barrel with the phosphate exterior finish.
It has become one of my favorite pistols!
You can see the chrome lined barrel at the muzzle in the second photo below.

IMG_20211116_143400002 by cee_Kamp 32ACP, on Flickr

IMG_20211116_143852576 by cee_Kamp 32ACP, on Flickr

Tony- agree on Bore Tech cleaners. For really bad copper or carbon fouling , I use Bore Tech’s Chameleon paste - it’s the equivalent of JB bore paste. A quick bore scope to determine which cleaner to use.