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Discussion Starter #1
Hello,

I just picked up the 17s a few days ago, took it apart to clean the parts of the factory oil/grease and noticed an odd mark on the piston I will post a link to an album that has pictures of the mark. The mark i am referring to is that little blotch on the bottom left of the pin in the photos, it feels somewhat rough when I run my fingernail over it and I cannot tell if it is stubborn grease/carbon build up from the factory test fire or of I have a bad piston straight from the factory. I cleaned the hell out of the piston face with a brass brush/cleaning solution but maybe i wasn't hard enough on that part of the piston. Any info would be appreciated, if it does look like there is an issue with that piston what is the best way to go about getting a replacement or any recommended sites to buy a replacement from?

17S piston - Imgur

I also had a hell of a time getting the firing pin retaining pin to go back in, I know it is not supposed to sit flush but all the videos I have seen previously of people cleaning their rifles just show it "clicking" back in, I did not force it in with a hammer or anything like that but i had to use the butt of a cleaning tool to press down on it with more force to get it to seat back in. Will this difficulty with that pin go away after some rounds have been run through the gun?

I can upload some pics of the retaining pin if needed.

Thank you
 

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That piston is fine. That thing is gonna look like **** after about 200 rounds anyway.

As for the retaining pin, I had a very similar experience the first couple times i disassembled the rifle. It's normal for it to be a little stiff at first. It will wear into it's familiar "click" after a while.
 

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There's nothing wrong with your piston or your rifle. Take it to the range or out in the back yard If you're in the correct area and shoot the jibeebus out of it. Enjoy.
 

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Dude...You got me (mentally) spun up for nothing. As the others said, it's gonna look a lot worse after you put a couple hundred rounds thru the pipe. I would also be careful as to how hard you scrub the piston and what you use to scrub it with. When you use wire brushes and solvents you're actually removing a little bit of material from the piston (in this case.) And by little bit, I'm talking like thousandths of a micron. Over time though, you can change the size of that part to the point of changing it's clearance in relation to the other parts around it.

Congrats on the purchase and welcome to the forum. Now stop worrying, go to the range and shoot that thang!
 

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I'd polish the face of the piston with some Flitz, and dremel with a felt pad. The closer you get to a mirror finish, the easier the carbon will come off. Your not gonna hurt the chrome finish any.
 

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Welcome to the forum! Congrats on your 17:?
 

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Discussion Starter #9
Awsome, thanks for the info that is what I was hoping but I am pretty paranoid about the condition of things especially my guns hah.
 

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Discussion Starter #10
Last Question, and thanks for all the input/info everyone. My mind is pretty much at ease now hah. Is this wear normal as well? This rifle has not been fired by me it has only been test fired at the factory, the cam pin is the one other thing i forgot to ask about. Pics here, 17S piston - Imgur cam pin is the last pic. I would think that that cam pin is supposed to look all black not marred up like that but if I am wrong let me know, other than these small issues that I am running into I cant wait to get out and shoot this thing if the damn weather would work with me a bit haha
 

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Discussion Starter #11
Will do I will make sure to not be as hard on it with the wire brushes, I had one other part I was wondering about the marks on that I posted a few replies down if you dont mind taking a look. Thanks again for the info!
 

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Mine looked way crustier that yours when I got it brand new off the truck.

It looks like some black volcanic rock now that it's been shot a bit but function is 100%.

I can hardly believe that all of that crud use to end up inside of my 308 AR instead of just on the piston face ::FF::
 
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