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Mos-Tek barrels, any reviews?

TonyTheTiger

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Minuteman
Feb 14, 2017
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In my never ending quest to get weird configuration barrels made I stumbled upon these guys.
They've got tons of options and their FB page makes it look like they're not afraid to make some odd things and work with you on custom contours and port locations. I just can't find much in the way of hands on reviews.
 
I have one in my radian builders set.

I wanted a 1:5 twist 300 blk and they made it. They are local to me, good people.

Fit and finish is great. I had to thermal fit the barrel to the receiver and thermal fit my slr sentry 7 to the barrel.

I just have an eotech exps2 on it so I can't really speak to accuracy as I basically just sighted it in as a large clover type group in the center of an 8" steel plate at 100.
 
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I have A few 350 legend barrels from them and they are excellent. Very good fit and finish and great customer service. The 350 barrels have been sub moa with factory ammo and 1/2 moa with handloads.
 
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Just placed an order for an unusual barrel configuration and got a text for me to call them. 8pm the night before Christmas Eve and they just wanted to double check order. I hope the barrel is as good as that service!
 
Just placed an order for an unusual barrel configuration and got a text for me to call them. 8pm the night before Christmas Eve and they just wanted to double check order. I hope the barrel is as good as that service!

Yeah they're good people. They texted and called me about a choice I made (a mistake) before making it.

Good luck, I've been happy with mine.
 
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I'm pretty excited for it. 10-12 week lead time isn't too bad either.
 
Well it's in. 17" RLGS +1", light contour. Looks great, extension was very snug in a few different uppers I tried it in. Feed ramps were polished out of the box.
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GB journal is apparently on the large end of spec, a couple different blocks were too tight without either a press fit or some hand fitting. Forgot to weigh it before install. Pretty excited to see how it shoots but this rifle build is low priority so it'll be awhile.
 
I heated my gas block in an oven and installed it on my mostek. I prefer a fit like that.
 
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I heated my gas block in an oven and installed it on my mostek. I prefer a fit like that.
Wish I would've thought of that. I just went real slow with some emery cloth. I do appreciate the tight fit though.
 
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I heated my gas block in an oven and installed it on my mostek. I prefer a fit like that.
Easy to put the barrel in the freezer as well. Same thing works if it's a tight fit to the receiver. Heat the upper, and chill the barrel
 
I have a 18” 6mmARC barrel from them. It shoots 87 - 108 grain bullets really well. I am using the 87’s for night time predator hunting. Off a bench it is sub-MOA and from a tripod I can hit 6” steel plates at 500yds. I would recommend them and wouldn’t hesitate to buy from them again!
 
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Accuracy results?
No clue yet, I'll rob a scope from another rifle someday if it ever stops snowing. It'll probably be a while before the entire rifle is finished, with the exception of the barrel it's all prize table parts and I'm not in a big hurry to get it done.
 
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Do they make the blanks themselves? Or are they sourced from Pac-Nor or Lilja or…? And then mos-tek finishes them to the customer preference??
 
That's a fine question, but one I have no answer for.

...based on correspondence I had with them a few years back when searching for 6ARC barrels, they sourced blanks back then. It's easily answered by e-mailing or calling them, Maquel is VERY good at responding and answering inquiries. This is current info on their website, "The precision blanks that we use to make your barrel are hand lapped, button rifled,"....
 
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Do they make the blanks themselves? Or are they sourced from Pac-Nor or Lilja or…? And then mos-tek finishes them to the customer preference??

...based on correspondence I had with them a few years back when searching for 6ARC barrels, they sourced blanks back then. It's easily answered by e-mailing or calling them, Maquel is VERY good at responding and answering inquiries. This is current info on their website, "The precision blanks that we use to make your barrel are hand lapped, button rifled,"....
She just got back to me. They do not disclose their blank source. Oh well, seeing how it shoots will be way more interesting to me than knowing it's origins.
 
She just got back to me. They do not disclose their blank source. Oh well, seeing how it shoots will be way more interesting to me than knowing it's origins.

....TBH, that was only a partial quote from their website, but it does narrow it down when one considers which barrel blank producers perform lapping of their blanks, either button or cut-rifled (or Mos-Tek" could be doing it once they receive the raw blanks....either way, it's definitely a desirable feature).
 
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This was with around 60-80 down the barrel. At the time I had a NXS 3-15 on it and was deciding what I would use the rifle for. Turns out, it liked 87gr VLDs and VMAX’s just as good, if not better. The rifle now has a XQ38 Thermion on it, shooting 87gr VMAX’s at 2790fps.

It’s a 18”, SPR/Med Contour, Rifle Length gas with a Superlative Arms gas block.
 
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This was with around 60-80 down the barrel. At the time I had a NXS 3-15 on it and was deciding what I would use the rifle for. Turns out, it liked 87gr VLDs and VMAX’s just as good, if not better. The rifle now has a XQ38 Thermion on it, shooting 87gr VMAX’s at 2790fps.

It’s a 18”, SPR/Med Contour, Rifle Length gas with a Superlative Arms gas block.
 

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Kinda forgot about this thread. Threw a spare PST 1-6x on the upper and got a rough zero with 55's. Loaded up four rounds of 69 SMK handloads and shot 3 into paper at about 65 yards, guessed holdover and put the last one centered on a 10" plate at 400 yards. I'd say this barrel is off to a good start.
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I've still got the cart before the horse in that I haven't really done anything like a thorough accuracy evaluation of this barrel yet, but man am I having a good time hosing with it. This rifle is so flat that I can confidently shoot pairs on targets partially covered by no-shoots at or very near the speed I would shoot a wide open target. Just ridiculous.
 
What muzzle brake are you using?
It stays very flat.
First video with the red lower is a Precision Armament Hypertap, subsequent videos are the Unrivaled Technologies brake. Both excellent brakes, the UT is more tunable but also bigger and heavier.
 
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Still haven't done a real accuracy evaluation yet but this is good enough for now.
Zeroing at 220 yards yesterday, Magpul bipod and a little rear bag, out of a truck bed, using a 6x scope with a 1.5 MOA center dot. Just my generic 69 SMK load, nothing tuned for this barrel.
4 shot group, 2.5", but the target is actually at about a 30° angle from my shooting position so the actual horizontal spread is sub 2".
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3 shot group at 2". Target is a 1/3 silhouette, it's easy to get a repeatable aim point left and right but harder to shoot the same elevation, I pretty much always have vertical stringing on a target this shape.
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Best 2 round group of my life. My spotter verified in real time that I stacked them.
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Considering my reticle covers over 3" at that distance I'm pretty happy with it.
 
I'm already thinking about ordering an intermediate gas 13.5" barrel. Too many irons in the fire to start a new project right now though.
What’s the shortest barrel you’ve run an intermediate gas system on? I’ve considered waiting for a 16” ultra match at the right price and chopping it to 14.5” or so but read conflicting reports on a 14.5” and intermediate.

Reliability would be very important to me and it would have a suppressor 80% of the time
 
What’s the shortest barrel you’ve run an intermediate gas system on? I’ve considered waiting for a 16” ultra match at the right price and chopping it to 14.5” or so but read conflicting reports on a 14.5” and intermediate.

Reliability would be very important to me and it would have a suppressor 80% of the time

Gas port size would determine reliability. If it's large enough and you have an adjustable gas block you should be fine. There are plenty of people running 13.7-13.9" intermediate. 14.5 should be fine. Especially suppressed.
 
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What’s the shortest barrel you’ve run an intermediate gas system on? I’ve considered waiting for a 16” ultra match at the right price and chopping it to 14.5” or so but read conflicting reports on a 14.5” and intermediate.

Reliability would be very important to me and it would have a suppressor 80% of the time
I've got a 15" and 16" intermediate. But I also have a 14.8" rifle gas that runs great even at far ends of the temperature spectrum, so I have no doubt that a 13.5-14" intermediate could work fine. I'm actually thinking about cutting the 15" down. And no suppressors on my end, so I'm even more sure that your use case could be made very reliable.
 
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Gas port size would determine reliability. If it's large enough and you have an adjustable gas block you should be fine. There are plenty of people running 13.7-13.9" intermediate. 14.5 should be fine. Especially suppressed.
Where are people getting 13.x intermediate barrels? I'd love to find one off the shelf, and I've looked quite a bit.
 
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Where are people getting 13.x intermediate barrels? I'd love to find one off the shelf, and I've looked quite a bit.

So Bexar arms had some available. Now I believe he is only building uppers. I believe you can send in quality parts and he'll build it but you can't just buy a barrel unfortunately.

Bexar original 13.7 intermediate barrels were made by mos-tek.
 
So Bexar arms had some available. Now I believe he is only building uppers. I believe you can send in quality parts and he'll build it but you can't just buy a barrel unfortunately.

Bexar original 13.7 intermediate barrels were made by mos-tek.
Bummer. I just checked out the website quick on the off chance they had something. Only Ballistic Advantage mid gas stuff in stock...
 
I'm just just teasing. Guess it was a bad joke. Sorry
I mostly figured that. My response sounds a bit testy in text.
That said, no one can say those are cherry picked, those are 9 consecutive shots to verify zero, not multiple groups with a picture of the best.
 
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Anyone else running these barrels? I’m considering having them make a custom tube for me.
 
Anyone else running these barrels? I’m considering having them make a custom tube for me.
I'll have a second barrel from them someday if that means anything to you. More unusual configurations.
The Hide is pretty hive minded about barrel brands, not sure you'll see many more owners around here.
 
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Been awhile. Anyone else have feedback/updates? I have a 1/5 300 BLK on order, and thinking of getting a .223 wylde from them if they can keep a great accuracy standard.