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JT's Matrix Build


jtallen83

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First 40 rounds downrange, short-strokes EVERY time, never locks back on the empty mag unless I do it manually..........sorry for the bad phone pics;

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I did my break-in routine for all 40 rounds, cleaned with No 9 and a brush letting it soak for several minutes then dry patches till they came out clean, then a patch soaked in gun juice with HBN then a couple clean patches before firing again.

First 20 were ZQI M80 clone ammo, first few rounds didn't hardly budge the BCG then it started to eject 2/3rds of them but wouldn't pick up the next round. 

This pattern continued with 20 rounds of Freedom Munitions remanufactured 175gr. match. I usually don't concern myself with accuracy at this stage but the last 20 put in one of the better break-in groups I've experienced, 20 rounds at 50 yards with the target flopping around in the wind on a left over political yard sign, I didn't really put any effort into it till half way through the box and I realized it might be a tight 20 rounder;

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I think this may be a good barrel for me but it won't do me any good if I can't get the function issue solved. I took the handguard off and looked for any gas leaks, everything was clean. No signs of any unusual wear inside or on the BCG. The gas block is still lined up where it was right on the pencil marks. I'm thinking I need more gas or less buffer/spring. Advice?????????/

The wilson BCG cleaned up real easy between the coating and the heavy dose of lube and grease. I did notice some cratering on the primers but no flat like a heavy pressure load would be, otherwise the cases that did get ejected looked good, seemed like I just read something about how this issue can relate to gas load but I don't remember where it was now;

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I'm at a loss......

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Edited by jtallen83
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My issue with xcaliber was that they jumped right into making you this barrel. I doubt they have made this 16" rifle gas configuration before and most likely didn't test it. I e-mailed  them twice and they answered my other questions but totally ignored my question about port size both times. I wouldn't be surprised it the used the same port size as the other barrel configurations and it's causing you to be undergassed. Maybe measure your port and compare it to what DNP or SS have? 

Criterion sold me because they spent a few months developing a functioning barrel. Tested it with several different brands of ammo before finalizing the port size.  

Edited by blue109
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JT    the way I measure my gas ports is with numbered drill bits or pin set.... but drill bits are #44 is .0860 a #45 is.0820 #46 is.0810    all mine are middy gas lengths and I have mine

at #44 which is .0860 and they work fine....  found a rifle length gas Lilja barrel  pdf and the port was .093  .hope this helps

very easy to drill...get a wood dowel rod and slide into barrel...so ya dont hit the other wall.....   .0935 is a #42       Wash

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Looks like I need to go to a 7/64 (.1094") as the Fulton 16 inch rifle length gas port is .1095". The 7/64 is closer to that than any numbered bit. I think I'll use the dowel and set it up in the drill press so I can 100% control the depth. I've got another comp day tomorrow so I hope to get it done and try a few rounds.

Thanks Guys!

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A number 43 bit is listed as .089" but I'm looking for .1095"?

I checked the present size with bits I have .077" fits, .083" does not fit. I'll get set up with the sizes between .089" to the largest.1095" and work my way up from the smaller till it functions.....I hope!

JT  good plan!    .083 with rifle length would be your problemo if its not fitting.......077 in a middy prolly wouldnt work very good...go bigger  ive had a .082 not cycle a middy 16" before when it was newish....so you are undergassed with the rifle length    Wash

Edited by washguy
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Now X-Caliber has offered to take the whole upper in and diagnose the issue, I put the emails quotes in the X-caliber barrels thread. Part of me wants to do this on my own for experience but then I worry I'll break a bit off per my usual luck. They won't give out the port size they use but mentioned this was a first for them. I couldn't get the bits here in town so I ordered a set, gives me a little time to think about the options.............

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     As you stated , my FA Criterion 16" with Rifle length gas system is 0.1095", I can see why you are short stroking . 

    Go slow so with the drilling as to not cause any chips hanging in the bore side of the hole & if you can , start with a slightly smaller Bit , as Matt described & try a function test with that size before you go to the next size .

    If you can & have the proper bits , Good Bits , no cheap ones , they , as you know , make a wide range of sizes , even special order a size if you need one .

     They won't give out port size ?  Why not ? They are far too easy to find out what they are . Send the barrel back & ask to have the gas port what ever you want , its your barrel or do it your self , just take it slow & easy .

    I'm not a Machinist ,but don't they make reamers in smaller sizes ? 

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     As you stated , my FA Criterion 16" with Rifle length gas system is 0.1095", I can see why you are short stroking . 

    Go slow so with the drilling as to not cause any chips hanging in the bore side of the hole & if you can , start with a slightly smaller Bit , as Matt described & try a function test with that size before you go to the next size .

    If you can & have the proper bits , Good Bits , no cheap ones , they , as you know , make a wide range of sizes , even special order a size if you need one .

     They won't give out port size ?  Why not ? They are far too easy to find out what they are . Send the barrel back & ask to have the gas port what ever you want , its your barrel or do it your self , just take it slow & easy .

    I'm not a Machinist ,but don't they make reamers in smaller sizes ? 

Yes, they do - here's an example, if the barrel is stainless you should consider cobalt or even carbide, might take a little searching to find and

since carbide is so brittle you would be best off with a vertical mill for accuracy and superior ability to hold the workpiece.

http://www.travers.com/high-speed-steel-special-decimal-size-chucking-reamers/p/57908/?lite=true

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Yes, they do - here's an example, if the barrel is stainless you should consider cobalt or even carbide, might take a little searching to find and

since carbide is so brittle you would be best off with a vertical mill for accuracy and superior ability to hold the workpiece.

http://www.travers.com/high-speed-steel-special-decimal-size-chucking-reamers/p/57908/?lite=true

Reamers are out! I can't pay more for an assortment of reamers than I paid for the barrel, this is just a hobby.....sorta.

I ordered regular HSS bits figuring I'd go real slow one size at a time with lots of lube, i figured I'd just bring the portable vise and cordless drill to the range with me.....if I don't decide to just send it back to X-Caliber and let them sort it out, tempting but I'd like to gain the experience myself plus I'd be stuck with whatever I tell them or whatever they decide. This is going to turn into an expensive build if I figure in tooling and then test fire ammo.......

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Heck yeah JT.....dont forget the dowel rod in the barrel...its a piece o' cake !   If X caliber knew their stuff they would have slapped a barrel on a rig and drilled till they found the sweet spot today already....I bet you and me got more rifles than they do... ... on second thought....they are prolly waiting on their shipment of barrels from China    sFi_fishwack.gif        Wash

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Hello everyone!,

  I am speaking on behalf of X-Caliber Barrels and Mfg.  We do test our port sizes on every gun we sell.  To assume that we guess all these things is ridiculous.  We test our gas ports with a carbine length gas buffer, buffer tube and spring and then with the rifle length gas buffer, buffer tube and spring.  And for everyone wanting to know gas port sizes, those are and industry secrets that are very valuable.  Why are you asking for them, because no body gives them out.  If they did the info would be all over for everyone to find but it is not because it is very valuable info.  The gas port sizes you guys are referring to from other companies, are these Armalite or DPMS? Is it DPMS Gen 1 or Gen 2?  As all of these have different tolerances and and call outs, THEY WILL ALL DIFFER.  Did you know if the changes by .001" it will change your gas port size by .010"?!?  Did you know changing your twist can change your gas port size .004"?!?  There is so much to gas porting and thinking what works for one barrel will work for the other, may work in some situations, but not gun barrels.  We have a company that takes 100 LR308 .308s a month and they consecutively ding metal at 900+ yards with no gas porting issues,  same barrel that is being discussed.  You can guess wrong about someone all day long but if you actually asked them there is no need to.  

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Hello everyone!,

  I am speaking on behalf of X-Caliber Barrels and Mfg.  We do test our port sizes on every gun we sell.  To assume that we guess all these things is ridiculous.  We test our gas ports with a carbine length gas buffer, buffer tube and spring and then with the rifle length gas buffer, buffer tube and spring.  And for everyone wanting to know gas port sizes, those are and industry secrets that are very valuable.  Why are you asking for them, because no body gives them out.  If they did the info would be all over for everyone to find but it is not because it is very valuable info.  The gas port sizes you guys are referring to from other companies, are these Armalite or DPMS? Is it DPMS Gen 1 or Gen 2?  As all of these have different tolerances and and call outs, THEY WILL ALL DIFFER.  Did you know if the changes by .001" it will change your gas port size by .010"?!?  Did you know changing your twist can change your gas port size .004"?!?  There is so much to gas porting and thinking what works for one barrel will work for the other, may work in some situations, but not gun barrels.  We have a company that takes 100 LR308 .308s a month and they consecutively ding metal at 900+ yards with no gas porting issues,  same barrel that is being discussed.  You can guess wrong about someone all day long but if you actually asked them there is no need to.  

Who sells a 16 inch rifle length gas system rifle in those numbers? I have not seen any commercially available.

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                               http://riflebarrels.com/wp-content/uploads/M4_navy.pdf                   http://riflebarrels.com/wp-content/uploads/ar10_740.pdf

 

 X-caliber sez  "  ridiculous.   .  And for everyone wanting to know gas port sizes, those are and industry secrets that are very valuable.  Why are you asking for them, because no body gives them out.  If they did the info would be all over for everyone to find but it is not because it is very valuable info."

I say you are full of crap  ....first place I pulled up has the full diagram of their barrels...everyone of them...with gas port  sizing......I venture to say that Liji which is not all that ,has sold more barrels made more barrels than you all have sold on.... wait for it..... Ebay    What you should do is just answer the phone for the sales dept....and not get involved in technical $hit of which you no nothing about   sCo_idk.gif      Wash

 

232 sold on Fleabay......   yep...thats where I buy all my fine barrels from 

http://www.ebay.com/sch/x-caliber/m.html?item=281795697374&hash=item419c551ade&rt=nc&_trksid=p2047675.l2562

 

 

 

 

 

 

 

                                                             

 

 

 

 

 

 

  

Edited by washguy
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My issue with xcaliber was that they jumped right into making you this barrel. I doubt they have made this 16" rifle gas configuration before and most likely didn't test it. I e-mailed  them twice and they answered my other questions but totally ignored my question about port size both times. I wouldn't be surprised it the used the same port size as the other barrel configurations and it's causing you to be undergassed. Maybe measure your port and compare it to what DNP or SS have? 

Criterion sold me because they spent a few months developing a functioning barrel. Tested it with several different brands of ammo before finalizing the port size.  

Did you know your response sounded unnecessarily defensive and a little bit catty? Welcome to the forum.

If you know what you are doing and have the right tools the testing can be done in a day.  You have an issue with us and I was informing you of how your assumptions were incorrect and how we do test every gas system for functionality with a variety of ammo on both buffer systems at all lengths because all lengths are different.  And we will happily answer any question that we can but most companies ask for a Non Disclosure Agreement before they give out gas port information because that is expensive info to attain.  

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"If you know what you are doing and have the right tools the testing can be done in a day.  You have an issue with us and I was informing you of how your assumptions were incorrect and how we do test every gas system for functionality with a variety of ammo on both buffer systems at all lengths because all lengths are different.  And we will happily answer any question that we can but most companies ask for a Non Disclosure Agreement before they give out gas port information because that is expensive info to attain.  "

Bull crap ..........Then why havnt you reproduced JT's problem with that same barrel today?    Wash

 

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You have an issue with us and I was informing you of how your assumptions were incorrect 

you could have done it without sounding bitchy lol. I made an assumption...JTs measurements seem to confirm that assumption. If the assumption was wrong and you have thoroughly tested thousands of 308 16" rifle gas barrels than great, we can move on to other areas of troubleshooting. That's kinda what we do here btw. Get 308ARs running. We don't have hundreds of members per week shooting 900 yds, but we do ok anyway. We may not have a huge active membership, but tons of people do pass through here on the quest for info. Keep that in mind.

Edited by blue109
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Hello everyone!,

  I am speaking on behalf of X-Caliber Barrels and Mfg.  We do test our port sizes on every gun we sell.  To assume that we guess all these things is ridiculous.  We test our gas ports with a carbine length gas buffer, buffer tube and spring and then with the rifle length gas buffer, buffer tube and spring.  And for everyone wanting to know gas port sizes, those are and industry secrets that are very valuable.  Why are you asking for them, because no body gives them out.  If they did the info would be all over for everyone to find but it is not because it is very valuable info.   

X-caliber, check out the thread that led to my purchase, your name is on it. You'll also get a better feel for the domain you're stepping into..........

http://forum.308ar.com/topic/11468-x-caliber-barrel-mfg-anyone-know-about-these/

More Top secret info here;

http://forum.308ar.com/topic/11861-measuring-and-drilling-gas-ports/#comment-162093 

Edited by jtallen83
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Here's some more super secret gas port sizing data for ya Phones sales guy at x caliber

geeez hope all this doesnt get out to the public  Wash

  

 

copy and paste                

A Krieger 20" RLGS I just worked on with .936" journal had .0935" port, like an AR15. I sealed the gas block and tube, and it was gassed very hard.

A Krieger 6.5 Creedmoor has a .086" port, RLGS and .936" journal.

Bartlein uses .086" for 6.5 CM and .260 Rem as well.

the BHW .308 based barrels are in the .085" (DPMS Pattern) gas port diameter for rifle length gas systems...keep in mind
that will very with the diameter of the barrel at the journal/gas seat (I.E., the heavy bull barrels with say a .936" dia. gas port seat
will need a larger dia. gas port). Also, keep in mind that the ratio of gas volume to port dia. is heavily biased (what this means is
a small Increase in gas port dia. yields a large gain in gas volume/port pressure...)

Edited by washguy
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