Weird barrel gunk inside new wolf a1 upper, help

[SS73]

Hi everyone,

Need some help here!

I got the wolf a1 upper when it first came out years ago, never had a chance to shoot it. Recently I took it out and and gave it a good cleaning before I was going to take it out to the range.

Everything looked ok , still covered in its factory oil, but when I clean the barrel I noticed a white dried gum-like substance inside the barrel (cover half of the chamber, and 2 lines going half way down the barrel at 12-o-clock and 6-o-clock, and half covers a 1’’ section near the end of the barrel). It feels rough/sticky and will catch the lint from my patches and q-tips.

I didn’t think too much of it, and proceed to attempt cleaning it out. I tried the usual clp + brush + patch didn’t do a thing.

So far, I have tried, clp, hoppes 9, break cleaner, kroil, and even 100% acetone. Even soaking It overnight has little effect on the “lines” and the muzzle end gunk, but was able to clean the chamber up to 70% with the help of an ar chamber brush.

I have never encountered this before, just wondering if any of you guys have experienced this. Any suggestions? As of now I’m beat, I’m about to take it to the range and put some rounds through the barrel to see if it would push/melt this stuff off.

Any suggestions would help, Thanks in advance.

[Arkane]

If you're sure it's not bad machining but some kind of dried up lube/gunk chuck a bore brush on a rod into a drill and shoot the barrel with seafom deep creep and slowly advance the rod into the barrel while spinning it, hitting it with lube to keep it from getting too fouled. When I got my first upper after a good initial cleaning I still had some issues with stuck cases. A good scrubbing with a bore brush on a road in the drill cleaned it right up. On my second and subsequent uppers I did this before going to the range and had no problems. Typical cleaning rod rules apply.

[SS73]

Thanks a lot for your advice, I’m off to get some sea foam deep creep, and I will report back

[SS73]

Update, Finally got to work on this again. Picked up some deep creep, didn’t use the drill method yet. Just the usual soak patch and brush, with a few shots of break free powder blast in between. I did see a little improvement to the barrel end near the muzzle section, but not much effect on the other areas.

Things I noticed:

1) It should not be a machine defect, on the thinner area of the gunk I can “see through” it and see the lands and groves of the rifling. And near the chamber I can see it wear off and show the darker color of the barrel.

2) powder blast/break cleaner is turning the “gunk” white.

3) the gunk seem to be fully hardened, tried to scrape it with a bamboo poker with no effect, it feels like concrete!

Also about the drill method, are you doing this just for the chamber or the entire length of the barrel?

Thanks again

[Arkane]

What I think this gunk is a preservative they coat the bore and chamber with after finishing, which I suppose is why a lot of solvents turn it white. I do the drill method in 2 steps. First off - I use 2 different cleaning rods both of which have had their sections screwed in with loctitie red so they ain't going anywhere in bore. I'll use a brand new M16 chamber brush and using the short rod I first shoot the chamber with the deep creep and then work the bore brush into the bore slowly and once I've got it seated move it in and out just a hair (and a slight bit of wobble when it's seated) giving it a shot of deep creep now and then to keep things lubed up.
On the bore I spray the bore down and then insert the rod from the muzzle end and screw on a bore brush at the breech end, shoot the barrel with deep creep again and slowly work the bore brush from muzzle to bore never letting it past the crown under power, giving it a shot of the deep creep along the way to keep it lubed. Unscrew, rinse, and repeat until it's clean. It won't hurt to use non chlorinated brake cleaner to flush things between scrubbings, just give it ample time to evaporate. Afterwards I flush everything and after it's dry give it a good coat of CLP with at least a few hours to allow it to soak into the metal before I run a patch.
The usual warnings: Do your best to keep the rod from coming in contact with the bore, and be extraordinarily careful not to damage the crown. I'm normally pull my flash hider when I do this so I can get a better eye on the crown.
I don't get crazy with the speed, just nice and slow keeping it lubed and ensuring the only things that contact the chamber and bore are the brushes. I didn't do this on my first upper and had problems with cases sticking the first time out even after a good swabbing and light lube. On the rest of my uppers I have used this method before the first range trip and have yet to have any issues with stuck cases.

[SS73]

Thank you so much for the detailed instructions Arkane!

I will try the drill method only if I am out of other options, I’m not 100% comfortable with it, because the chances of me damaging the crown is a possibility. Maybe if I could go In from the receiver end with a bore guide it could reduce that possibility.

I’m going to try the “long soak” (2 days at a time) method with different chemicals, and use my usual Otis flex rod patch and brush.

So far deep creep didn’t do much to help, I’m trying kroil now, going with hoppes 9 next. I will keep everyone updated. But I got a feeling the drill method will have tobe used.

Again, thanks a lot for the info

[SS73]

Thanks a lot for the detailed instructions Arkane.

I think my last post got lost somewhere, so this may be a double post.

I am not 100% comfortable with the drill method till I have exhausted all other options, I really don’t trust myself with the possibility of damaging the crown. Maybe if I go from the chamber end with a bore guide it will be less likely to damage the crown? I will however try it in the chamber area.

I’m going to try a “long soak” method, basically letting the solvent sit in the bore for 2 days at a time, then do the usual, Otis cable brush/patch. So far I have tried with deep creep and kroil, going to try hoppes 9 next, hoppes 9 has a copper solvent in it we will see if it will attack this gunk better. If all else fails I will do the deep creep drill method.

Again, thanks a lot for the detailed reply, I will post my findings here

[Arkane]

On the bore that's what you should be doing, starting from the chamber end and pulling towards the muzzle. I stop the drill before the brush bristles clear the crown. As long as you keep a slight pulling tension on the rod it shouldn't contact the bore.

[Veitch]

How hard should you be pulling towards the muzzle?

[Arkane]

How hard should you be pulling towards the muzzle?

Just use enough pull to move the brush towards the muzzle slowly, and keep it lubed. That gives the brush enough dwell time to scrub without developing a lot of heat. Also try not to reverse the direction of pull while in bore.

[SS73]

Thanks again for all the help, I couldn’t bring myself to drill-brush the barrel as Arkane suggested, I don’t trust my skills at this. I tried my best with the normal cleaning methods, Pretty much the gunk was unchanged other than a little improvement near the muzzle side. This stuff in the barrel is hardcore！. I gave up and took it to the range, I thought maybe I can shoot it out, or become a bit softer with heat.

Range report:

After 60 rounds, that gunk did not change at all, crazy stuff!!!

But good news, no FTE! No stuck cases! But the bolt is not holding open on a empty mag about 80% of the time, and when it does it will drop if I move the gun, or release the mag. I think 2 times it did short stroke and not pick up a round.

I am suspecting I am over buffering. Currently I’m running a Spikes T3 buffer w/ wolff extra power springs. What do you guys usually run? H2?

I need to pick up the t91 simple rear sight, that taller front sight that came with the upper is seriously thick!

[Arkane]

At most all it needs is an H2, and that just smooths the recoil out a bit. The drill method is safe, just use a good phosphor bronze brush.