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Discussion Starter · #1 ·
Can someone briefly go over how to remove the piston for cleaning? This is the first piston rifle I've owned. I've put about 400 rounds thru my SCAR 16s and wasn't sure if it was time for a good cleaning. The rest of the rifle is no problem, similar cleaning procedure as an AR-15 except much less dirty.

I'm sure this was most likely covered already in a previous thread, if that is the case if someone can link the thread it will be much appreciated. Any tips or things to watch out for will be very helpful.
 

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With the carrier removed I take the end of my cleaning rod and lightly tap the end of the piston forward(from the back of the gasblock inside the receiver), with a few taps the piston comes out.
 

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We use a magnet to pull the gas piston from our 17Ss, then we use Flitz to clean it, alcohol to remove any remaining Flitz, and push it back into place.
 

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Discussion Starter · #5 ·
Oh, well that sounds simple enough, I was thinking some disassembly of the front block was required. I'll give a try later today. Thanks guys!
 

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Oh, well that sounds simple enough, I was thinking some disassembly of the front block was required. I'll give a try later today. Thanks guys!


It is pretty simple once you've done it.







Remove the gas selector plug



Push the piston out from the rear.


 

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Discussion Starter · #8 ·
I got the gas selector plug out but the piston does not want to come out. I stuck my cleaning rod inside and tapped on the back but it wouldn't budge. I made sure I was tapping in the right place because when I can push the piston from the front to test, the area I'm pushing with my rod does move the piston forwards, but only to its original place, does not come fully out like in Talhoffer's 3rd picture. Frankly I banged it from inside the receiver pretty hard, I don't want to damage anything. Any ideas?
 

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Discussion Starter · #9 ·
I got the gas selector plug out but the piston does not want to come out. I stuck my cleaning rod inside and tapped on the back but it wouldn't budge. I made sure I was tapping in the right place because when I can push the piston from the front to test, the area I'm pushing with my rod does move the piston forwards, but only to its original place, does not come fully out like in Talhoffer's 3rd picture. Frankly I banged it from inside the receiver pretty hard, I don't want to damage anything. Any ideas?
Im an idiot. I went at it with a cleaning rod with no attachments. I stuck a brush on it and bam, came right out. Must be a sleeve design housing the piston which the rod on its own was too thick to get to. :-D
 

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Discussion Starter · #11 ·
Just got done cleaning everything. So that's where all the carbon was hiding all along. Some of the most dense gunk I've seen. Would it be wrong of me to say that it feels like just the piston area and barrel/chamber needs to be cleaned occasionally? The rest of the receiver, bolt carrier, bolt and trigger didn't get very dirty at all even after several hundred rounds. I am starting to think maybe those components (not including piston and barrel of course) could go a couple thousand rounds in between cleanings as long as they're properly lubed.
 

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Manual says to clean the piston and gas block every 1k rounds or 400 rounds if using a suppressor. I agree that the other reciprocating parts stay way cleaner and wetter than any DI AR.

Depending on local shooting conditions, you might get away with less frequent cleaning. Where I shoot it's often dusty and I'd rather clean the grit out of the rife sooner rather than later.

H
 

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I found it's very easy to remove the piston by taking an allen wrench, putting it through one of the vent holes in the upper, line the allen wrench up with the piston and use the bolt carrier to tap it out. For me, it's a lot easier than trying to line up a cleaning rod.

After a few rounds suppressed, there's no way I would be able to get it out with a magnet! Or at least with any magnet I own!
 

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What do y'all do to clean out the piston chamber, just a dry rag?
 

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Removing the gas piston. If you don't have a magnet or a suitable cleaning rod, a piece of wire from a coat hanger about 4 inches long will do. It needs to have a slight curve on it. insert it into the second vent hole counting from the front. NOW PUT YOUR EYE AT THE BACK OF THE RECEIVER SO YOU CAN SEE THE TAIL OF THE PISTON - this enables you to aim the wire rather than just poking around at random.
 

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Dobe, I use multiple Q-tips to clean in the gas piston area, just dry thou no cleaner or lube. I also use the " clothes hanger " method to get that piston out. I clean my rifle(minus the part above the barrel I can't reach) after every range session.

How often do members on here actually take off their barrel to clean where you can't reach?
 

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Dobe, I use multiple Q-tips to clean in the gas piston area, just dry thou no cleaner or lube. I also use the " clothes hanger " method to get that piston out. I clean my rifle(minus the part above the barrel I can't reach) after every range session.

How often do members on here actually take off their barrel to clean where you can't reach?
Never, and I don't ever plan to.
 
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