Gunsmithing gas hole on AR barrel

[eli polite]

i have a 16" m4 barrel i bought it on gun broker it is from a well known manufacturer.

here is the problem i was pre fitting it to the upper today and i noticed the gas hole is not centered it is roughly 1/8" off to the side of where it should be.

i don't want to go through the hassle of contacting the guy sending it back and all that crap. this gun is not going to be for accuracy it is for fun body size silhouettes at 200 yards or less. it will most likely never have a scope on it.

so here is the question= on the gas block can i put it in a press and widen the hole (drill it at an angle) in order to get it to line up with the hole on the barrel without messing up the function of the gun.

 

[GuyCoker]

Re: gas hole on AR barrel

What kind of gas block are your running? if it is just going to be a low profile gas block It can be fitted and slightly off without much problem. If it is a fixed front sight I would send it back. I definitely wouldn't drill it out due to gas flow issues.

I am not a gunsmith BTW, just on the internet.

 

[eli polite]

Re: gas hole on AR barrel

low profile hidden under the arm guard.

 

[RADcustom]

Re: gas hole on AR barrel

If you are set on using it then offset the gas block to line up with the hole and bend the gas tube slightly so that it enters the receiver straight. This is assuming you are using a round tube that has clearance for the rotation of the block. I agree not to do any drilling on the hole.

 

[eli polite]

Re: gas hole on AR barrel

thank you all. the gas block will be hidden. i figure by the time i contact this guy ship it out have him ship it back and all that crap it will tie the barrel up for a few more weeks. or i can put the thing one and be done. if it were going to be a high end rifle i would go through the trouble but its not

 

[Mike_in_FL]

Re: gas hole on AR barrel

I'm definitely no gunsmith but may I make a suggestion before you try and assemble this? Hopefully you have a go gauge and a bolt. I would try to check headspace by hand before assembling it to your upper.

I would be concerned that the barrel extension has turned or moved and that's why the port is off. I saw something similar like this happen with a Mossberg 500 barrel. I know sending it back would be a hassle, but safe is best.

 

[colchester]

Re: gas hole on AR barrel

I would check to see if the hole is off center or the barrel extension is timed incorrectly

 

[DBMG]

Re: gas hole on AR barrel

Most gas blocks have a oversized gas hole to start