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98Z5V

98's 12.5" Sig Barrel .308 Win Pistol

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On 5/12/2020 at 11:53 PM, 98Z5V said:

The Secret Ingredient in these barrel builds is to... punch that pin out and get rid of it.  That was a Sig thing, to cure a problem that didn't even exist in the first place... 

You had to search around for an extractor that would work with it - punch it out, run a standard extractor, zero issues.

I don't think that pin was the issue with that D Wilson BCG, the thing wouldn't work in my Matrix build either. Tried it with that original P.O.C. Andersen barrel and again with the Faxon barrel. It had extraction problems with both of them. I ended up putting a Toolcraft BCG in that one and no more problems. I think Dave Wilson's extractors were out of spec somehow. I contacted him about it just after I started having the problems and he sent me that BCG rebuild kit that he had on his website, which had another extractor in it. The new one didn't work any better than the one that came with the bolt.

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Got the Troy fixed iron sights today - DDs were sold out everywhere I was looking, and I've used the Troy's before - so they got the nod.  WOA gas tube arrives Friday.  Might be able to shoot it this coming weekend.  I know I threatened paint before now, but I'm waiting on two key things for it, before I paint it.  I need them, before I can paint.

Here she sits - and if I can get that gas tube in it, I'll shoot it on Sunday morning.  :thumbup:

P1080700.thumb.JPG.62a90acde3f38ff5b696a7a35ec62d79.JPG

Edited by 98Z5V

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This little fucker is ready to go. The WOA gas tube came in today - perfect timing for the weekend.  It's getting shot in the morning, and that gas port is gonna get drilled until it runs right.  Lube will definitely NOT be the issue - she's ready, as far as that goes.

The 11.000" White Oak gas tube worked out perfect.  Measurements were on the money for that one. 

P1080702.thumb.JPG.f539b7d902579193b3fbaeb55a2c8260.JPG

We've seen one recently that someone order a 11.250" gas tube, and it looks/ends just like mine.  It's SUPER important to measure each one of these SIG 12.5" barrels before you just blindly order a gas tube, just because someone else had a length that worked.  With the report of the 11.250" tube that looked just like mine above, I'm convinced that these barrels were blown out because the gas-port-drilling-monkey at SIG was just putting them where he wanted them - whatever worked on that shift.

That's the only answer for a quality barrel like this, blown out at $50 each - they were blems, because the port distances weren't uniform.

With my measurements, I determined that I needed an 11.000" gas tube for mine.  Ordered it via WOA website, didn't have to talk to John on the phone.  Told them I needed 11.000" OAL with a .308AR/AR-10 bend in the tube. That's exactly what I received.  And exactly what I needed. 

With my gas port location, I'm exactly 3.500" from the center of the gas port to the end of the barrel - 3.500" dwell time.  Those with longer gas tubes, like the 11 1/4" gas tube here - that's a shorter dwell time, down to 3.250" dwell.  Which one is what SIG really designed?  Who knows. That dwell time difference will definitely affect whatever we need for a functional gas port diameter, though, when the barrel is this short, and the dwell time is this short. 

Edited by 98Z5V

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11 hours ago, 98Z5V said:

That's the only answer for a quality barrel like this, blown out at $50 each - they were blems, because the port distances weren't uniform.

Maybe, they also showed up at CDNN right after Sig discontinued the P716, a very short run. They started out at $99 and didn't move in price or in-stock numbers for a good while.  Mine are as uniform as my measurements can get, did notice a couple had slightly different port measurements but otherwise uniform for both styles they sold. That longer measurement we heard always had me puzzled.

No matter why they blew them out they make for a super fun build for a discount price. Wonder if that guy on GB ever got the $500 for his?

11 hours ago, 98Z5V said:

Which one is what SIG really designed? 

Best I can tell without beating the pins out of the gas block my P716 is the 3.500" dwell time. I have not found anything to indicate they ever did anything different there, changed up the gas block but the operating rod has the same part number. 

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Complete success this morning, complete.  Didn't have to touch the 0.070" gas port, not even a little.  The 11.000" gas tube is right on the money, length-wise, and the very first round out of the gun locked the BCG back on the empty mag.  This thing ran like a champ.  I had an old batch of 150 FMJ-BT handloads that I wanted to shoot up, so I fed it the whole bag.  There were about 80 left in that bag, and this thing ate 'em all and didn't eve hiccup once.

Damn, I love this little bastard.  Even the iron sights were right on, right out of the package and onto the gun.  GPJohn had two 8" plates set up at 30 yards, and it was .308-on-steel right away.  I'm sure they need tweaked a little, but I didn't even take targets out there today - just wanted to get this thing to run - and, MAN does it run!  Now, I wish I would have taken some real targets, and dialing this thing for 50 yards. 

I've been on a Primary Arms pre-order for about a month and a half for this:

https://www.primaryarms.com/primary-arms-slxz-advanced-rotary-knob-micro-red-dot-sight-fde

 

MD-RB-AD-FDE_00.jpg?resizeid=7&resizeh=0

Got my shipping notification yesterday.  This thing went together smoothly.  :thumbup:

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On another note - got to run the new IWI semi-auto shotgun today, too.  5-shot tube, three of them, rotating.  15 loaded, with another in the chamber.  This is sweet.

P1080704.thumb.JPG.20552790a8da55b94c3d3abdd845278b.JPG

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:thumbup: They are a BLAST! So far what I've put together has worked from the go with that factory gas port, thought it worth noting a piston system gas port size translates to a DI system. 

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On 5/24/2020 at 2:47 PM, 98Z5V said:

Complete success this morning, complete.  Didn't have to touch the 0.070" gas port, not even a little.  The 11.000" gas tube is right on the money, length-wise, and the very first round out of the gun locked the BCG back on the empty mag.  This thing ran like a champ.

Damn, I love this little bastard. 

They are even more fun with a suppressor!😁

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On 5/24/2020 at 2:19 PM, jtallen83 said:

:thumbup: They are a BLAST! So far what I've put together has worked from the go with that factory gas port, thought it worth noting a piston system gas port size translates to a DI system. 

This is a very, VERY valid point...   :thumbup::hail:

18 minutes ago, 392heminut said:

They are even more fun with a suppressor!😁

I need to work on that, something fierce.  That is my major shortcoming in this game...   :bitchslap:

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On another note, Primary Arms "exceeds course standards" once again.  My original tracking on that red dot stated it would show up on Thursday - tomorrow. It actually got here yesterday (Tuesday).  I mounted it up last night.

Next thing is the paint.  This pic sucks...

1533216318_12-5ShortyDone.thumb.jpg.7e926203e4a736a0166b5649bfc9caab.jpg

 

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On 5/27/2020 at 7:56 PM, 98Z5V said:

On another note, Primary Arms "exceeds course standards" once again.  My original tracking on that red dot stated it would show up on Thursday - tomorrow. It actually got here yesterday (Tuesday).  I mounted it up last night.

Next thing is the paint.  This pic sucks...

1533216318_12-5ShortyDone.thumb.jpg.7e926203e4a736a0166b5649bfc9caab.jpg

 

Damn, that's a nice looking little bastard right there. How does the SBA3 hold up to 308 recoil? I've got 2 of those braces, but I've only ever used them on my 10.5 5.56 build and a 7in AR9. Always been curious how they hold up to big boy calibers.

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24 minutes ago, DayWalker said:

How does the SBA3 hold up to 308 recoil? 

I have put them on several 12.5 inch 308 builds and never seen an issue. The earliest style Sig brace on my P716 had issues creeping up the pistol tube but the SBA3 is rock solid.

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1 hour ago, DayWalker said:

Damn, that's a nice looking little bastard right there. How does the SBA3 hold up to 308 recoil? I've got 2 of those braces, but I've only ever used them on my 10.5 5.56 build and a 7in AR9. Always been curious how they hold up to big boy calibers.

So far, so good. Only about 100 rounds through this one, at this point, just to break it in and test function.  The SBA3 works.  :thumbup:

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