I emailed Larue and I just don't want shoot 150 if anyone has had a similar issues.  Does anyone know of a better fix to the problem I am having.

I am having feeding issues with my new Larue 308.

It randomly has feeding issue where it will jam the cartridge as it tried to move into the chamber and get stuck,

I have experienced this with both  federal 168gr federal match king and 150 gr federal powershok.



I was using magpul magazines but even tried it with the larue steel one supplied. This would happen in both.  Sometimes with the larue it would eject and totally skip over the brass leaving it in the magazine. I am not sure if they were seated perfectly but this happened a few times on the limited ammo I used to see if I could find a common thing



The bolt would remain open after firing the last bullet in the magazine except one instance where it closed up after the last round was fired.



I manually filled my magazine and pulled back the charging handle and letting the bolt close and pulled it back and it would eject the ammo in the magazine upon each time I pulled the handle back, The ammo casings came back clean without any marks on them.

Response

I see you only have 30-40 rounds through it. Typically we recommend a minimum of 150 rounds before we consider bringing it in for inspection. This is because we use a chrome silicon buffer spring and it takes about that many rounds to take a “set”. Using a full synthetic oil like our machine gunners lube and getting the buffer spring broke in will typically solve these feeding issues.

Well in my ever so humble opinion, a rifle that costs what a LR does, ought to run OUT OF THE BOX. Having built several thousand AR 15s and AR 10s during the last 5-6 years, and using every kind of spring and buffer on the market at one time or another, in my experience, this is a problem rarely encountered. and when we did run into feeding issues like you describe, a SLIGHT enlargement of the gas port was the most frequently applied and most commonly successful remedy. I do not recall ever hearing any company telling us that the springs we bought from them, often 500 at a time, needed to be "broken in", as a precursor to proper functioning when installed as designed, in a rifle. The biggest reason we had very few returns for cycling issues with our guns was that we tested any parts from new suppliers before putting them into the mix. And we tracked any returns that came in until they were fixed.

I am not saying that LR does not do this. EVERY gun maker has an occasional lemon. And in our case, we simply replaced the offending parts/gun for the customer without hesitation. And went over the returned item with a fine toothed comb until we found the problem.

Please keep us posted with what happens. I am ready and willing to accept LR's statement, if they can demonstrate that this is in fact a common occurence for their rifle/spring combos installed in their product. And assuming this is the case, one would reasonably expect that there is some sort of documentation as regards this issue and the frequency that it arises.

NOT TRYING TO "dis" a site sponsor/industry member in any way, just think in this case their response is disappointing. Were it my rifle, I would be annoyed.

Did you assemble the upper or did LaRue? Is it possible the gas block isn't lined up completely? Are you using a rifle length extension or a carbine tube and stock? I'd sit on the couch and cycle the thing a hundred times or so and then try again. Both of my UU kits haven't had any issues.

The upper was assembled buy Larue.  My local AR shop put the lower and upper together.  Everything was lubed or greased. I can't imaging that many rifles go out the door with similar issues.  It is disappointing but I will likely just give it time till I get that many rounds down the rifle.  It is just annoying that I have to rack the bolt back as often as this is getting jammed while feeding the cartridge.  The cartridges also have a big indentation where it is getting jammed.  So I lose out on the defective ammo as well.  

Would you try shooting the indented cartridges as well.  I figured I would not risk it.

I wouldn't fire the dented rounds myself. I'd probably use some old NATO 308 instead of wasting match ammo for break in. It should run direct from LaRue, but I'd try to follow their recommendation before returning for inspection because who knows how long that might take. I'd probably also leave the BCG locked to the rear for a day or so. I've done this with new pistols and encounter less feeding issues than just loading up and shooting. It always sucks when things don't work right every time right out of the box.

Whose BCG are you using and what's your buffer weight?

@txhunter2

I know your frustrations....

I have a Larue 762 OBR, not a UU, but I am sure similiar mechanical set up, and I fought this rifle for a long time.  It went back to Larue twice and on the second return trip, after they said "we did not find anythig wrong, ran fine for us"  and they essentially said I was on my own, I reached out to Slash at Heavy Buffers and talked to him.

Now, I was running suppressed, the OBR has the PST (Port Selector Technology-Larue acronym for selector switch) for Suppressed/Non-suppressed.  But my rifle was doing exactly what you described.  I mainly shoot (99% of the time) 168 FGMM and was using some cheaper ammo to sight in when I first got the rifle.  But the rifle was doing this non suppressed and more suppressed.  

Slash recommened his XH buffer and spring set up.  Dont quote me, but it is about 8 ounces in weight, and this along with some break in time, helped a whole lot.  I also found, and dont laugh, but I run my rifles "wet" with a lot of lube and grease.  I use a lot of grease on my 556 BCGs and did the same with the OBR and that was not good.  I cleaned the BCG and went with straight oil and this too helped.

Now I took the 762 OBR out about 6 months ago and it did do the same thing one time, I switched mags and it did not do it any more....which brings me to the mags, I use mainly Magpul mags for the range, but also have Lancers and Knights Armament mags and IIRC, the feeding issues are not with the Lancers or KAC mags.  Just to note, my Larue mags that came with the rifle are still in the wrapper and never been used.  I have read the Larue rifles (762) run best with their mags....I have never verified.

As what @ToyCop said, for what these rifles cost, my OBR was $3300, they should function out the door and make you coffee in the morning...needless to say I was very disappointed at first....my 556 OBR and UU rifles are good though.  

Keep us updated, I am curious to see what you come up with....with all this writing I just did, I am going to get up and pack my Larue OBR and bring it to the range this morning.  I am also going to dig out my Larue mags and give them a try.  You see what not sleeping and awake at 3:30 AM will do to you  

Yeah it is frustrating.  The rifle is setup with the larue lower and all parts including the buffer came directly from Larue.  I may take it apart and make sure it was all lubed with oil and wipe down any grease.

I tried the Larue steel magazine and it was not any better than the magpuls I ran.  I may reach out to slash about XH buffer and spring.  I am will keep you posted as I have time to get out and shoot it more.

Have fun a the range.

Thanks

@txhunter2

Any updates?  Have you shot the rifle more?  Still experiencing the same issue?  Asking for selfish reasons as I have a Larue UU kit that I will be building this weekend and was wondering if you had any lessons learned.

I actually got out today and fired about 30 rounds with no issues.  After the last email I probably cycled and racked the bolt carrier manually about 200 times.  I also locked the bolt back for about 2 weeks after that process.

Today it ran without any problems and I am glad I did not have to fire lots of rounds to see if that fixed it.  I will give another update after my next time out.   Hopefully this is the fix it needs I just wish it would of run without issues like my other AR308 and AR15's.

I mounted my new super hogster thermal  to it and got it sighted in as well.

Thanks for the update, glad it worked for you today!  Good luck!  Subscribed for the next update.

I built and installed the UU kit on a Larue lower today.  Got sidetracked with kid duties, so I did not finish mounting and sighting in the scope.  That chore is for tomorrow.  I will probably get to the range on Tuesday or Wednesday.

ETA:  correct typo

Hopefully yours will run great without any issues.  I am sure it is probably pretty rare it was just frustrating that it did not run correctly from the start.