Posted: 12/30/2014 8:39:43 PM EDT
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Rifle is an 18" 7.62 predatOBR and i am having a difficult time with a few things with it, and would love some help, insight or suggestions to make this a more enjoyable experiance.
My fist concern with the rifle, being a left hander is that ejected brass very often hits me in the face. Its a safety concern and i dont want to end up injured should a case get past my glasses, ive also developed a hell of a flinch in anticipation of getting hit. I have tried a H buffer instead but still end up getting plastered. This seems to happen more frequent with lighter ammo like 150gr vs heavier 168 or 175gr, but does happen with both. I have also made sure im not on the supressed setting of gas block. This first issue is my primary concern as i dont want to get hurt and leads me to my second concern. All to often the rifle fails to eject at all, the spent brass is extracted from the chamber and then gets bunched up with the round being fed in creating a traffic jam. This happens multiple times per mag, larue mag or pmag doesnt matter. Aside from not working safely or consitantly for me at this point, I am wondering if others are able to get lighter rounds to group. I get seriously get wild groups with anything around 150gr , like 6-7 moa. As soon as I put in 168/175 FGMM it easily groups 1/2 moa. I know its recomended to feed it only match ammo and some of the ligher stuff i have ran through was but still couldnt group it well enough to establish a zero. Any help at this point would be much appreciated, as id love for the enjoyment to match the expense at this point. recap of things ive tried: cleaning it H buffer Pmags assorment of ammo 145-175 grain run it wet, like real wet Best results have been with 168/175gr FGMM, better ejection pattern and reliability, amazing groups. side note: rifle is cerakoted if that matters... Thanks |
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You might try a brass deflector that clips on to the rail. I have seen this work for lefty's with 5.56, might work with 7.62. You may still get hit in the chest or shoulder but at the bench, the deflector bounces it down onto the bench.
As for 150 grain ammo, my 14.5", 7.62 tOBR runs perfectly with PMC bronze 150 grain or Fed XM80 147 grain. Probably 1-1.5" groups with the cheap stuff at 100. FGMM does drop it down to 0.5" but both cycle just fine. I would probably give LT a call, based on my experience with just one tOBR, it sounds like something is wrong. |
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I would also call larue,but did you shoot it prior to having it coated?
I think I would lube the bolt and rails and hand cycle it a hundred times then try another box of fgmm and see if it will start running better.maybe the ceracoat tightened things up too much? Pete |
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Quoted: At this point my brass isn't even hitting the deflector. The rifle wasn't shot before cerakote, also I had the same problems on another rifle with same set up just different cerakote color, rifle has 200 rounds or so in it and prolly 200 more hand cycles fyi  |
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Quoted:
At this point my brass isn't even hitting the deflector. The rifle wasn't shot before cerakote, also I had the same problems on another rifle with same set up just different cerakote color, rifle has 200 rounds or so in it and prolly 200 more hand cycles fyi Is the inside of the upper coated? The bolt? I'm struggling to imagine how Cera cote would slow the bolt enough to cause the brass to miss the deflector. |
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the upper lower and rail inside and out were done, not aware of places it shouldnt be, i have many riles coated and they all look similar, it is possible that with the tight tolerances of the weapon the bolt has been slowed time will tell with further break in.
where are others having their brass eject mine is 5-5:30 ish, not hitting the defector |
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Quoted:
the upper lower and rail inside and out were done, not aware of places it shouldnt be, i have many riles coated and they all look similar, it is possible that with the tight tolerances of the weapon the bolt has been slowed time will tell with further break in. where are others having their brass eject mine is 5-5:30 ish, not hitting the defector Have a good feeling this is your problem... This is a match grade rifle with TIGHT tolerances already, tight just got tighter. As others have said, lube her up and hand cycle the shit out of it. |
| The best way to solve the lefty thing is to run your scope farther back on the rifle and extend your stock farther to accomodate. It would be best to run a prs stock but you can accomplish the same goal with a collapsible, but it looks a little odd. If your face is farther back you shouldnt get hit. |
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Quoted:
the upper lower and rail inside and out were done, not aware of places it shouldnt be, i have many riles coated and they all look similar, it is possible that with the tight tolerances of the weapon the bolt has been slowed time will tell with further break in. where are others having their brass eject mine is 5-5:30 ish, not hitting the defector That is one hellova expensive paint job. Call it a hunch, but I don't think LaRue does quality control by eyeballing parts. I bet QC ensures every part is within a hundredth or thousandth of an inch. The cerakote just changed that. |
| Remove the cerakote from the inside of the upper where the bolt rides. Cerakote wears really well so I don't expect it to wear off anytime soon.... I've put 1500 rounds through my Kimber (that has been cerakoted) and you can barely tell there is any wear on the ejection port where the casings hit it. In the mean time, run a lighter spring or run heavier loads. The heavier loads have more recoil and thus are why they seem to work better. I would also find another company to do your cerakoting, one that deals with precision weaponry. Wilson Combat did my Kimber, as well as my gas piston CMMG AR-15, and they did not do the inside of the upper or lower...... |
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I am a lefty and the brass hitting me is a fact of life. Many of the gassers I own do it. You are right when you speculate it will happen less with heavier rounds. I only use 168 gr A-MAX or 175 gr SMK so it isn't bad. Your position on the stock relative to the optics is also a factor. Try adjusting things around to see if you can reduce the occurrence. I don't mind it at all. You won't either after a while if nothing else works. I haven't had any of the other problems you describe. On the few occasions that I have fired lighter rounds, Hornady 150 gr SST, my accuracy degradation was minor if at all. Call the shop. BR,
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I read back through your posts. Are you shooting the rifle in the suppressed position without a suppressor? The rifle is not made to reliably function in this position withou a suppressor. Secondly, if you are shooting the rifle with the PST in the proper un-suppressed position and both cerakoted rifles gave you the same result the issue Is, or I would bet the farm is, directly related to the coating as others have already said above. Having 1 Larue that has issues....RARE.... having 2 Larues with issues .......the proverbial needle in a haystack...buy a lottery ticket.
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| I'm going to give the shop a call on my next day off, I did go through and remove a bit of the coating inside the upper and make sure it's slick as shit, scrubbed it all up, drenched it in oil and put another 60 through it. Also did about 500 hand cycles. I did shoot some cheaper light ammo as I'm out of the heavy stuff and I think I had 4 FTEs, ejection pattern still jaw jaring. I did also notice when going through the upper that the bolt group had plenty of play everywhere so no binding as far as I can see |