Discoloration around front sight

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[ARCHIVED THREAD] - Discoloration around front sight

Posted: 8/14/2005 3:39:41 PM EDT

Hello all,

I've got another newbie question here. I was cleaning up my rifle and noticed an orange-ish/brown-ish color around where the front sight is attached to the barrel.

I bought the upper as a kit, so I didn't mess with this part when putting things together. I've only taken her out twice and cleaned thoroughly both times, so I can't imagine it's any sort of rust, but the color worries me.

Is there something used during installation of a front sight that would cause this 'residue' around the barrel? Am I worrying too much?

Please see pic below. You're looking at a close-up of an A-2 front sight on a 16" M4-type barrel.

Thanks for your help.

http://geocities.com/golanalog/image/frontsight.jpg

Posted: 8/15/2005 3:40:02 AM EDT

[#1]

it's rust from the barrel being Parkerized as whole instead of properly done in pieces. Whose barrel?

Posted: 8/15/2005 4:46:24 AM EDT

[#2]

I got the kit from M&A Parts. What should I do about it?

Thanks.

Posted: 8/15/2005 5:52:18 AM EDT

[#3]

pull off the FSB and Parkerize each part separately.

Posted: 8/15/2005 7:04:51 AM EDT

[#4]

Tweak,

I called M&A and they're going to replace it. But thanks to your reply, I was at least able to sound like I knew what I talking about when I called to complain.

Thanks!

Philter

Posted: 8/16/2005 1:50:49 AM EDT

[#5]

outstanding. now the next time you hear someone say that Parkerizing the barrel intact doesn't harm anything you can throw in some first hand contrary knowledge.

Posted: 8/16/2005 4:38:10 AM EDT

[#6]

Quoted:
outstanding. now the next time you hear someone say that Parkerizing the barrel intact doesn't harm anything you can throw in some first hand contrary knowledge.

So are you saying some park solution that remained between the FSB and barrel after the park process caused the corrosion?

Posted: 8/16/2005 4:54:46 AM EDT

[#7]

Quoted:
Quoted:
outstanding. now the next time you hear someone say that Parkerizing the barrel intact doesn't harm anything you can throw in some first hand contrary knowledge.

So are you saying some park solution that remained between the FSB and barrel after the park process caused the corrosion?

The park solution also contains water and is usually dried prior to being oiled.
The discoloration is caused by a lack of atttention to detail by whoever parkerized it.

The orange/brown stuff is rust.

I have parkerized fal, AK, AR, Galil, G3 and others with the gas block installed, or in some cases with the reciever and barrel assembled, and never had an issue.

The key is to make damn sure you get all the water/park solution out of it prior to oiling or painting the assembly.
A good air compressor with a standard air nozzel works fine if you can keep water out of the air lines.

Posted: 8/16/2005 6:57:31 PM EDT

[#8]

the better solution is to Parkerize the barrel as the print shows, in separate parts. You can remove all the Park solution you want. Won't matter in the least the next time the rifle gets wet.

Posted: 8/16/2005 9:47:31 PM EDT

[#9]

Quoted:
the better solution is to Parkerize the barrel as the print shows, in separate parts. You can remove all the Park solution you want. Won't matter in the least the next time the rifle gets wet.

When I parkerize I let them sizzle for wuite a while and have never had a problem.

I even submersed a few of my rifles and never had any issues.
Just so ya know I wasn't bump firing under water or anything.
They were in the back of a truck when we got stuck in some water while 4X4ing.

My ARs, Fal, and AK were under water for about an hour, I parkerized all of them myself.
Took them out and let them dry and no rust.

link to larger pic

Posted: 8/16/2005 10:04:41 PM EDT

[#10]

I'm thrilled that you have rifles made from rust proof steel. You should contact COLT and FN and sell it to them. They could save a lot of time and trouble Parkerzing their barrels.

Posted: 8/17/2005 8:00:06 AM EDT

[#11]

Quoted:
I'm thrilled that you have rifles made from rust proof steel. You should contact COLT and FN and sell it to them. They could save a lot of time and trouble Parkerzing their barrels.

Right,...

....I think they have a nearly rust proof steel, it is called stainless and I think they have already heard of it.

Anyway, All I am trying to say is if regular steel is parkerized right it is possible to avoid the issue.

Oh yah, nothing against you personally but, FUCK colt in their non-civilian supporting asses.

Posted: 8/17/2005 8:06:11 AM EDT

[#12]

Hey Tweak, does COLT parkerize the FSB after it is reamed to size? Or do they do they parkerize the barrel only? Surely they wouldn't leave the FSB bore unprotected and prone to oxidation.

Posted: 8/17/2005 11:25:25 PM EDT

[#13]

Quoted:
colt

has nothing to do with COLT, this procedure is outlined in the print for the part hence demanded by the milspec.

numbers,

The bore of the FSB is reamed after Parkerizing for the tightest possible fit. The finish left by the reamer inhibits rust to some degree as does the unfinished surface being pressed against a Parkerized surface.

Posted: 8/18/2005 4:25:36 PM EDT

[#14]

Even Bushmaster does it the half a$$ way but I can't imagine why? Thats not even one cent of Park where the finish is missing.

Also, is the finish on AR barrels Parkerizing? Because I thought it was some other type of finish.

Posted: 8/18/2005 8:18:16 PM EDT

[#15]

Quoted:
Even Bushmaster does it the half a$$ way but I can't imagine why? Thats not even one cent of Park where the finish is missing.

Also, is the finish on AR barrels Parkerizing? Because I thought it was some other type of finish.

Some people use parkerizing and some use a phosphate system.
I think it is phosphat???, not sure of the correct term or spelling.

You are correct about bushmaster though, no park under the site base.

Posted: 8/18/2005 8:23:36 PM EDT

[#16]

The reason manufacturers park after the fsb is installed is for looks. You will notice that most colt barrels have scratches on them in front of the fsb new out of the box. This is from installation of the fsb after the barrel has been parked.

Posted: 8/18/2005 11:05:45 PM EDT

[#17]

I've never seen a COLT barrel with scratches forward of the FSB from installation. Handling and normal wear and tear yes.

The cloners contradict the print to save money as Parking after assembly takes less time and effort.

Parkerizing is the trade name for phosphate coating.

Posted: 8/19/2005 6:44:01 AM EDT

[#18]

Phosphate, that's what I remember. Thanks!

[ARCHIVED THREAD] - Discoloration around front sight

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