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X-Caliber Barrel & MFG, Anyone know about these?


jtallen83

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"I would be happy to get that back from you to check it. We do test our barrels before we do gas port sizes and make sure it works with carbine and rifle buffer systems and we do not give out the gas port sizes as those are valuable 
industry secrets so when people ask we do not answer the question of gas port size."

"-It could be the barrel but I might be able to diagnose it better with all your stuff in it."

I'm torn now, send it in or drill it out myself??????? I had to order a set of bits as nobody had them here in town.

 

Thats some pure crapola right there lol       You can doo it JT  drill it brother...    go big or go home     sFi_flamethrower.gif    Wash

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This looks pretty cool!

Don't these guys make the barrels for the new DPMS GII rifles!

 

I remember the owner of a barrel place in Montana had a video where he leaked that he was making barrels for a new dpms rifle, which I automatically thought of as the GII, but I forgot the guys name and company!

 

Anyways, I was thinking of a pencil weight 16" rifle length gas system for the wife... What do yall think? It should shoot like a powder puff especially with a comp on it.

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Got another email today....looks like they want to get this configuration figured.

"--It sounds like the gas port, and if it is, there will be no charge to you. If it is something else other than the barrel, you will be charged return shipping and a small fee for shop time, but like I said I am pretty sure it is a 
gas system issue. Also if you could measure the length of the buffer, spring and count the number of coils on the spring that would also be appreciated to full know all the parts of this equation. "

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  Fuk that , sorry for my grammar . They might be reading these posts , but I've never been one to hold back on an honest opinion .

 

 The Buffer system is a logical one to look into , but I thought we already went over that . BCG locks back manually with the Bolt Catch , right ?

Edited by survivalshop
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If it was the buffer system then measuring and counting will mean nothing. I sent them a link to the Aero kit I used. Just well send the whole rifle so they can get some real R&D benefit from it............I did send them a link to the JT's matrix build thread so they could get a feel for what has been done so far. I honestly think they want to fix it...for me and so they know what to do on the next one. I wouldn't mind but it is a pain in the arse to mess with shipping when you work out of town. 

Another plus to letting them fix it is all the test fire ammo I'll save!

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  Fuk that , sorry for my grammar . They might be reading these posts , but I've never been one to hold back on an honest opinion .

 

 The Buffer system is a logical one to look into , but I thought we already went over that . BCG locks back manually with the Bolt Catch , right ?

JT knows what it takes to have the proper buffer system...sheesh.....Like I said before...bet there's not an ar308 within a 100 yds of this shop...if there is...why dont they slap a barrel on with their gas port like they sent JT and see how that works out for em?

JT ...they gonna pay for shipping both ways on your stuff? if not...thats a lot of ammo money..... its just plain under gassed with that port size.... drill it out..aint no big deal   ...I dont want anyone doing R%D with my rifle...whatcha gonna feel like when it comes back marred up from shipping or sumthin....heck they couldnt even get a bare barrel to you without it getting messed up    Wash

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My issue with the AP .308AR receiver extension parts was with the extension.  It's got a lip on the bottom, and that lip needs notched for the buffer retainer.  If you don't notch it, you're hitting the buffer retainer - and the tube needs to go in one more full turn.  For emphasis - THE TUBE NEEDS TO GO IN ONE MORE FULL TURN.  It must, or it's not gonna function correctly. 

Mine was giving me fits, and didn't measure right - you can get around the extra 0.100" in depth and still have a running rifle.  But only if you notch that bottom lip and turn the receiver extension in one more full turn.  Once I notched it and screwed the damn thing in, no more issues.

I know I mentioned that enough to get the attention of the AP owners...   lmao...

JT, perform that task and function test the rifle again, before you send it in, brother.

Now...  where was that a$shole that said people should just shut up and contribute, or say nothing.  Where's that fucker at...

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I didn't notice any issue with mine, not hitting anything and functioned fine with dummy rounds. I can cut the notch and see where it gets me though, there was a bit of thread left but no more than on the AR I built or my other rifles. I remember you saying there needed to be a notch but figured AP must have changed it......

What will this 1 turn do that stops the short stroking? I'm not sure I understand what the issue there could be?

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What will this 1 turn do that stops the short stroking? I'm not sure I understand what the issue there could be?

I initially had an issue on an AP set with the AP carbine recoil system - too much bolt travel, rearward.  It was effing up the recoil stroke, and dropping rounds.  I immediately checked how far the bolt face was traveling back, beyond the bolt catch, and it was a pretty good distance - too much.  So, just like AR pistol caliber builds, on bolt carriers that don't have a true "bolt" that reciprocates - there's too much rearward travel.  You stack $1.75 in quarters in those bastards, and they function fine.  Or, you buy an expensive buffer that's exactly $1.75 longer, and it functions fine.  That special buffer is a damn bit more expensive than $1.75, too.

On my initial AP set run-in, I had those malfunctions.  I noticed the additional backtravel, and measured the internal depth of the extension, the spring, and the buffer length.  The spring and buffer were good, but the extension measured out at 7.100" internal depth, and should have been 7.000" internal depth.

So, working with an extension that's 0.100" too long, internally.  I think I stacked up $0.75 or a dollar, and shot it again - problem solved.  I think I went with a buck, first, and dropped it to 75 cents.

At any rate, I didn't like that solution, got pissed off, and ordered a complete Armalite AR-10 carbine recoil system for it - ran that thing like a scalded dog.  Not a hiccup.  I was gonna throw the AP extension in the trash, but held onto it - I ended up putting it in the lightweight 5.56 rifle, as a temp, until I can get the right parts for that rifle. When assembling that one, I noticed that the extension barely made contact with the buffer retainer, so I really started looking at it.  I tried to put it another turn in, and it wouldn't go - hit the lip on the bottom of the extension against the retainer.  Pulled it, notched it, reinstalled it another turn - and that thing runs like a champ now, too, with that extension installed on it.

So, you're working with an additional 0.100" in internal depth, plus there's 0.050" between threads on the extension/lower receiver, so you're out another 0.150" more than having the right parts made the right way.  That additional 0.150" will cause the back of the bolt carrier to strike the lower receiver, and fuk your recoil impulse/recoil cycle all up - and possibly cause extraction/ejection problems.  Did on mine.

This is what it does to your lower receiver... In the pics below, you can clearly see that the bolt carrier struck the lower solid in all four corners, and did it a few times.  After solving this problem, there haven't been anymore problems.  That's definitely enough contact to completely fuk the recoil cycle all up, and cause some other cycling issues.

 

 

 

P1040518.JPG

P1040519.JPG

P1040520.JPG

P1040522.JPG

Edited by 98Z5V
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   Photo's didn't show up on my PC , Your issue with your AP Buffer system is why I brought the Buffer system issue up . The edge or lip at the Bottom of some Receiver Extensions I thought were made for anti tilt when used with Piston systems or STD systems .I think I have one Receiver Extension with that lip & it has a notch for the retainer in it .

  Strange how so little of a measurement difference can cause issues with these rifles . Its easy enough to take another Receiver extension & try it , to see if it is the issue , but if your Gas port is that small  , that's another issue in its self .There is no magic in Gas Port sizing , it has to be large enough for it to work the action properly , with Barrel length , caliber & gas system length.

Edited by survivalshop
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Odd - the pics are directly uploaded into the thread, straight from the hard drive.  No links - straight uploads.  Drew needs to look at that, and bitch-slap, or at least "strong pimp hand" the people setting up the new board here.

I'll go upload the shiit to a host and link the bastards...

Thank God for Photobucket, because Invision Powerboard certainly can't get it done - here are the pics from the post I made above...

P1040518_zpsfjzbuoyy.jpg

P1040519_zpssbdcbbfo.jpg

P1040520_zpscbp13rib.jpg

P1040522_zpsfntca3cr.jpg

Edited by 98Z5V
Reason for edit - Invision Powerboard can't get it done...
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No marks like that on mine but I cut the notch and added 75 cents to give me a strong 1/8 inch between the bolt face and the bolt catch. More details and questions posted in the JT's Matrix Build thread.

Measured the port with my chinese calipers and bits, .0805 or a #46 bit is where it is at now. I'll test the extension tube alteration first and if that doesn't do it I'll start opening up the gas port a size at a time.

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how the hell did I miss this the first time!  I hate havin to explain why I'm laughing to the wife though. 

but wait...in a post here it was a typo someone said....it was a 100 yds     lol     Wash

 

here it is from dnp

DNP

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Posted 6 July · Report post

Whoops. Decimal error. That's 100.0 yards.

 

Edited by washguy
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  • 4 weeks later...

Follow up on the X-caliber barrel. When zeroed for 168 gr FGMM it will peg the bull on the first shot but starts to spread as soon as the heat is on;

0148e304271eb556b0030aa234b72f6566d9aad001082d86b87142f298579e871649598fbc7a44ec

The first 5 rounds of the day and the last ten were with MK319 ammo, I blew a shot on the ten round group but I'll take it I guess. The first five were the best of the day, right now I'm thinking this barrel does not respond well when hot. My AR-10 chrome lined 20 inch will out shoot this barrel so far............ 

017a45280259ac82ec93bf9042b0977ae62bf14301791c5ecb75d94697e7eb16814b1d077e76ae4e

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