H322 and green deposits

[Krazykarl]

Just got done cleaning my colt AR15a4 and immediately noticed something odd. The rifle was difficult to operate in that the charging handle was hard to pull back. I finally got it open and field stripped to find the following. See attached pictures....

The rifle was shot Thursday. About 180 rounds of my own reloads. Using H322 and nosler 50 gr bt. The precision was very good. I was very pleased until it came time to do some cleaning. I have used h322 in other cartridges and rifles with no ill effect. Maybe it is not meant for AR or I just need to clean the day of rather than putting it off.

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[opngrnd]

H322 is a common powder for 223 on this forum. Maybe someone else can chime in.

[Krazykarl]

Powder charges went from 23.0, 23.5, 24.0, 24.5. no signs of overpressure. 23.5 actually shot the best with consecutive 10 round groups at 1.08 and 1.25 MOA.

[mark5pt56]

Just a reaction of the solvents/lube and the powder/carbon/copper residue.

[md66948]

Just a reaction of the solvents/lube and the powder/carbon/copper residue.

I have to go with Mark. My first thought was a reaction to something you used to clean and/or lube your AR.

[Krazykarl]

I start with Butch's bore shine bore cleaner. Patched and brushed . Then the bore is dry patched. Oiled with Mobil 1 synthetic for the last step.

[lsllc]

This looks to me like the results of leaving copper solvents in the rifle and firing it. Clean it up with a copper solvent, completely remove solvent, and lubricate it and keep on.


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[Krazykarl]

What really threw me off with this situation is that my other Colt uppers have never done this before with similar cleaning techniques.

It was too easy for me to blame it on the H322 as it was the only variable that was unchanged. I have never seen green deposits like this before with TAC, Varget, H355, WW760, etc. The S&B primers, Winchester primers, and CCI primers have also behaved appropriately. First time I ever used h322 in an AR and 2 days later you saw what I had.

The unfortunate thing about the green crud is it acted like glue and really prevented the gas rings from releasing from the carrier. It took some effort to work the action.

[Dino11]

I just recently built a beater AR so I could lend it to friends that wanted to go shooting with me, and to have something I could abuse and not worry about.

Took it to the range about a month ago and put the same amount of rounds down the pipe as you. Ammo was my own reloads, 22.5gn H322, 55gr Hornady FMJBT, and CCI 400 primer. This is my go to load for plinking and shoots sub MOA thru my better rifles which are pretty high end. I also use Hornady SP boat tails the most and they seem to be a little more accurate.

The attached picture is after the rifle sat for a month with out cleaning, I was going to wait until I put a couple hundred more rounds thru it before doing an actual cleaning. Was just going to inspect and lube for the next outing.

As others have stated some thing else is contributing to your condition, H322 powder is a top tier powder and is used by some of the top match rifle shooters.
You will not find a better powder to use for light to mid weight bullets in an AR.

[Krazykarl]

I do not want to give up on H322 as it performs well with other rifles and cartridges. It produced very acceptable precision out of the 20" Colt without much effort.

I need to definitely rethink my cleaning procedure as it appears that aggressive copper solvents like Butch's bore shine may be the culprit. Probably enough residue left in the gas tube to become a problem.

Thanks for everyone's help!