Advice on a barrel for Stag 10 build

[Mystic Precision]

I bought a shilen SS select match for mine. I have only completed a OCW test with a chrono graph so I haven't officially shot for groups with it but what appears on paper at 200m look promising.

However the indexing of the gas port and extension is very off. The gas block is properly aligned with the hole. The rifle is leveled in the picture. I feel like for the price of these custom options they should be better than this. Luckily the function of it seems fine so far.

Odds are this was done to ensure the gas port hole was in the groove... not in the lands or some combo of that. If there are any issues with accuracy, let me know and it will get fixed. I suspect the barrel will shoot very well.

And isn't that what matters most?

Jerry

 

[Sinasta]

Odds are this was done to ensure the gas port hole was in the groove... not in the lands or some combo of that. If there are any issues with accuracy, let me know and it will get fixed. I suspect the barrel will shoot very well.

And isn't that what matters most?

Jerry

Is there proof that a gas port not in a groove will cause accuracy issues?

 

[Mystic Precision]

Is there proof that a gas port not in a groove will cause accuracy issues?

Good question... I will refer to those who compete that do well and seem to demand it in their barrels. of course, they are also demanding high quality match barrels so...???

From a SWAG observation, I can't see how a land partially cut with a hole in it would be a good thing. In general, the gas port is drilled towards the bore and there really isn't a step to get rid of any burrs that may occur (that I am aware of)

Don't know about you but I have certainly seen burrs on the exit side of metal that I have drilled holes in. If there is a tool or step that avoids this, that would be awesome... I suspect there is.

And if there is a burr around a "C" put into a lands, how good is that for the jackets as they scream by???? How good would it be even if there was no burr????

Personally, it would not be something I would want in my match barrel if it could be avoided.... YMMV

Jerry

 

[Twan]

I bought a shilen SS select match for mine. I have only completed a OCW test with a chrono graph so I haven't officially shot for groups with it but what appears on paper at 200m look promising.

However the indexing of the gas port and extension is very off. The gas block is properly aligned with the hole. The rifle is leveled in the picture. I feel like for the price of these custom options they should be better than this. Luckily the function of it seems fine so far.

That's ridiculous. Gas ports are drilled into barrels after the extension is installed (or they should be)... in the order of processes - this is done so that the port is properly indexed relative to the barrel extension pin, so that everything lines up when installed. Function might certainly be ok - even great, but realistically the port should be aligned significantly better with the extension pin. The downside to a canted gas block like you're experiencing is also the gas tube alignment to the carrier key when the bolt is in battery. You might experience un-even contact or rubbing on the gas tube where it enters the carrier key.

 

[Twan]

Good question... I will refer to those who compete that do well and seem to demand it in their barrels. of course, they are also demanding high quality match barrels so...???

From a SWAG observation, I can't see how a land partially cut with a hole in it would be a good thing. In general, the gas port is drilled towards the bore and there really isn't a step to get rid of any burrs that may occur (that I am aware of)

Don't know about you but I have certainly seen burrs on the exit side of metal that I have drilled holes in. If there is a tool or step that avoids this, that would be awesome... I suspect there is.

And if there is a burr around a "C" put into a lands, how good is that for the jackets as they scream by???? How good would it be even if there was no burr????

Personally, it would not be something I would want in my match barrel if it could be avoided.... YMMV

Jerry

In general, a gas port is drilled towards the bore? How the crap else would a gas port be drilled into a barrel... from the inside? As for any burrs - a special tool? You can knock a burr out with a pass of a bore brush, or the manufacturer should be doing some finishing steps to ensure the burr is cleaned out - if there is one.

Go look at plenty of match accurate barrels for semi-autos, and certainly including the AR15... many of them will have a port that might not align perfectly with a land or groove - there are far greater things that would affect accuracy than the location of the port relative to the lands and grooves.

 

[Brian46]

Faxon, ctcs has an 18.6" or buy a 20" pencil and have it cut down

 

[Bare]

My ibi creedmoor barrel is amazing with the 130gr ar hybrids. So far that’s all I have shot. Factory gold metal match with this bullets was so great I ran it through the chronograph and matched the velocity with my reloads and I was off to the races. So far 500-1000 yards has been relatively easy for first round hits. Great barrel

 

[Mystic Precision]

The downside to a canted gas block like you're experiencing is also the gas tube alignment to the carrier key when the bolt is in battery. You might experience un-even contact or rubbing on the gas tube where it enters the carrier key.

I have certainly not played with every version of part and upper but with the AR's I have seen, the gas tube seemed to be aligned by a hole or slot in the barrel nut....but if that was not available, it was definitely through the hole in the upper

Just never thought that hole in the upper could be that big to allow the gas tube to be "pushed" to one side.... but like I said, I most certainly have not seen every possible AR part.

And the gas tubes I have played with were pretty bendy making it very easy to reposition it if needed... but again, maybe most are rigid and can't bend??????

Jerry

 

[Mystic Precision]

I am sure there are all sorts of ways to make "match" stuff... I have certainly not shot every barrel out there.



But for me, this type of performance is what I would like in my match AR10.

YMMV

Jerry

PS.. all sorts of specs and options possible from McGowen, Shilen, Krieger and IBI. All make very good match barrels

 

[ColinD]

I'd get an IBI. I've been researching the same for a stag build that I plan on doing for the exact same purpose as you.

 

[Bartok5]

A properly stress-relieved barrel will not string nor will the Mean Point of Impact shift when the barrel heats up. Take a look at any NATO self-loading Battle Rifle manufactured from the 1950s to 80s for a clue as to the necessary thickness of barrel required for military service. The FN FAL, M14, G3 and AR10 are all "Pencil Barrels" by today's standards. Those barrels were capable of reasonably accurate, rapid-fire for multiple 20-round magazines, followed by a sustained "normal" rate of fire for up to and including the entire infantry basic loadout of the day (200 rounds for Canada; 5 x 20-round mags plus 2x 50-round, stripper-clipped bandoliers). In other words, Battle Rifles were run hard and chrome-lined pencil barrels carried the day. That said, 2 MOA was considered acceptable accuracy for a service rifle, whereas today's shooters may demand more.

The real questions are what do you plan to do with your rifle and how accurate do you need it to be? For plinking or Service Rifle competition, 2 MOA from a Pencil barrel regardless of the barrel temperature may be perfectly acceptable. A hunter may insist on 1 MOA from a cold bore and never fire more than a 3 round group before cooling. In this case, an accurate cold-bore Pencil barrel would be optimal for weight savings. Yet another sort of competitor may insist on sub-MOA over prolonged courses of fire vis-a-vis modern PRS matches. In this case, a heavier "DMR" barrel profile is probably most appropriate. Considerably heavier than a Pencil profile, but also likely to be more consistent over long courses of fire and better able to absorb heat (thereby avoiding premature throat erosion).

Ask yourself what you plan to do most with your Stag 10 and then select the appropriate barrel in terms of profile/material(s)/weight and the barrel's warranteed accuracy standard. Then spend your money. Accuracy isn't everything. Neither is light weight. Everything is a trade-off. Be honest with yourself regarding your needs and means, then research and purchase accordingly.