Gas cylinder on semi auto

mockba77

mockba77

CGN Regular
Rating - 100%
92   0   0
Location
Victoria, BC
My newly purchased shotgun had a gas cylinder that was all spotted. I contacted a manufacturer and was told that it's absolutely normal. Probably, oil dried on the coating and penetrated inside. I was advised to clean it with a solvent. A solvent didn't solve the issue and I simply polished the gas cylinder. Now it's just a shiny metal that looks nice. Now my main concern is do I need to repaint it with cerakote, for example, or I can leave it as it is? What is this thin coating on a gas cylinder for? I checked other similar new shotguns in the store and they all have some spots and scratches on the the coating. Does this coating help to protect the metal at all? Against rust, carbon dioxide or something else? To me, it's much easier to clean a gas cylinder right now because it's polished but I would like to hear your opinions if possible. Thanks to all in advance.
 
Last edited:
Is it stainless? If so no problems, if not it may rust eventually. On the semis I own you cannot put oil on these parts or they will accumulate gunk too quick and cause malfunctions.
 
I'd of left it as is myself, but you didn't harm anything with what you did either. Just wipe it with oil as a precaution and it will be fine.
 
It's not a stainless steel. From what I know this part, as well as gas piston cannot be oiled as stated Hunter 5425 earlier. I just wonder what is this original coating for? To mask the imperfection of cylinder or something else? Especially considering its bad quality - again, new guns have scratches on it here and there. And again, I can apply a cerakote on it (heat resistant 1200F) that will be much better than the original coating but is it worth extra money I will have to spend? Can anybody describe how exactly this part of a gun is being affected? Semi-auto owners - how your gas cylinder does look like?

Magellann, I would have left it as is if it didn't look like spots of rust or unknown blemishes. I just like my firearms look good and "fresh" :)
 
Last edited:
It's fine just shoot the gun and keep it clean. The carbon will coat it between cleanings.

It's a hidden part internal to the gun and supplies it's main action function it doesn't matter what it looks like as long as it works.
 
I just spray mine down with gun scrubber solvent and wipe with a rag on my sx3 and let it air dry before reassembling.
 
Yes, standard cleaning procedures ... I just can not understand the purpose of this original coating?! There are not too much heated gas is outside that can affect the metal gas cylinder but can not do the same to a plastic forend. Obviously, this coating is not for protecting the cylinder against the heated gas. But then what for?
 
Last edited:
Beretta typically test fires their shotguns before shipment. I don't think it is a coating per se but a byproduct of the test firing. Looked at my A400 Xplor and it would be consistent on what I see on my gun.
 
No, it's a grey coating on the metal. Spots are probably oil that dried out. That's what Beretta told me. I couldn't remove this spots with solvent though ...
 
Last edited:
mockba77 said:
100% agree :) But it didn't answer my question - what is this coating for?
Click to expand...

It wasn't a coating. It was oxidation. Beretta has never applied a finish to the gas chambers on their semi auto shotguns. The gas chamber was forged, then had its inner diameter machined and honed to correct dimensions. The outer was machined as well...as was the surface area that contacts the barrel was also machined to the proper contour before being silver brazed to the barrel. The outer was left in its raw state as any corrosion on that part will not affect operation. The Browning and Winchester gas guns are the same...no finish on the gas chamber!
 
VLT79 said:
It wasn't a coating. It was oxidation. Beretta has never applied a finish to the gas chambers on their semi auto shotguns. The gas chamber was forged, then had its inner diameter machined and honed to correct dimensions. The surface area that contacts the barrel was also machined to the proper contour before being silver brazed to the barrel but the rest of it was left in its raw state as any corrosion on that part will not affect operation. The Browning and Winchester gas guns are the same...no finish on the gas chamber!
Click to expand...

Thanks VLT79.
 
Last edited:
You must log in or register to reply here.
Back
Top Bottom