Changing gas tube length
- Thread starter Jdiep
- Start date
There may be people on the board that use their rifle for patrol or protection but I'd be willing to bet that anyone that does is using an issued firearm and not swapping barrels from 20 to 14.5 which is what the OP is doing. The OP is obviously talking about his personal range plinker and does not have an Armourer taking care of his rifle. I'm pretty sure that if you work for an agency that issues a firearm for you to work with you can't just start swapping out barrels.
There is no danger to cutting the gas tube shorter other than that it may not work so if he wants to do it to save $20 or because he's too impatient to wait till after he drives 15km to one of the local retailers to purchase the right one then I say go for it.
As I have pointed out an over gassed AR will cycle every time regardless of the condition of a tube. Having said that a improperly fitted tube will lead to excessive fouling of the bolt and may lead to operating problems. If someone wants to save a few bucks on a engineered piece of equipment then go ahead.......its not the best course of action in running with a warn out or cut tube when dealing with DI firearms.
You can drive a Hellcat with drum brakes but would you?
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Lol didn't cut it. The gun range I go to just told me to bring in the rifle and they will fit it for me. Way eaiser. Thanks for all the help yall I was just being impatiant and cutting it takes 2 mins. But I rather have it work right then me messing it up
I don't buy either of these statements.
The first one is wildly over generalizing. You saying that a gas tube that has burst will still let the rifle function? Don't think so. Not to mention that this statement basically invalidates your argument that a modified gas tube will cause cycling problems. If the gun will cycle regardless of gas tube condition then how can altering a gas tube cause cycling problems?
Second one makes no sense either. The DI system funnels gas straight into the space between the bolt and carrier. How could a badly fitted tube make that worse?
Gas tubes are not precisely flared at the end. They are the same size as halfway down the tube. There is no flare whatsoever. There is a chamfer to guide the tube into the key in cases of misalignment.
The gas tube does not seal against the key. There is at least .007" clearance on diameter between the ID of the gas key and the OD of the gas tube. So there is absolutely zero seal between the two. (If one's gas rings had .007" clearance they would be considered worn out and replaced, not that they are providing a 'seal'.)
There is quite a bit of gas leakage in a 'properly tuned' (read: not overgassed) ar15.
The gas tube does not seal against the key. There is at least .007" clearance on diameter between the ID of the gas key and the OD of the gas tube. So there is absolutely zero seal between the two. (If one's gas rings had .007" clearance they would be considered worn out and replaced, not that they are providing a 'seal'.)
There is quite a bit of gas leakage in a 'properly tuned' (read: not overgassed) ar15.
How? Specifically.
If the tube is long, it won't leak gas any more than it usually will. If it's too long to the point the carrier won't close, it wont leak gas at all because the gun won't fire.
If it's so short that it doesn't even enter the carrier, it wont cycle at all and the gas will be vented into the upper. While it may foul the carrier/receiver, the bolt (that is locked in the B.E.) will likely not get much fouling on it.
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