Fort Tom Posted March 6, 2015 Report Share Posted March 6, 2015 Hope someone can help me out here. I bought a LNIB DPMS Oracle, at a price I couldn't pass up. After I got it home and started tinkering with it, I found out that the BCG would stick when I pulled on the CH. This would come and go, intermediately, and my first thought was, "this is why I got a LNIB gun so cheap". I stripped the bolt, couldn't find anything, inside of upper receiver looked great, I couldn't find anything wrong. Bolt closed with no problems, gas block and tube lined up perfectly. It just stuck randomly. Anyway, I did the following, making so many changes that I thought the problem might be the stock BCG and stock CH. I changed out the hand guard and gas block with a Midwest Industries 15" rail, and I think it was a Bravo Company gas block. Changed out stock DPMS BCG and CH, with a Rainier Arms NiB BCG and a Bravo Company MOD 3 CH. Other stuff, CMC 3.5 trigger, KNS Non Rotating pins, MBUS, Scope and Magpul CTR, couldn't have any impact. So I started pulling the CH and dry firing, and soon I would yank on the CH, and it was stuck again. Had to keep "popping" the CH, and eventually it will let go and charge the bolt again. Same thing as with the DPMS BCG and stock CH. Checked the cam pin "ramp", it didn't look like it had any burrs, or any other obstructions. Out of desperation, I lubed that bolt until it was dripping of CLP, and kept working the CH back and fort, approx.a 100 times. It finally started working every time. Due to snow (we got crazy snow for KY), I haven't been able to get it to the range, to shoot it, but after today, I'm not sure I should. I pulled it out of the safe to get a shotgun out for a hunting trip, decided to give the CH a good yank, confident it would operate just fine, and bam, it stuck on the first try. I cycled it a few more times, and it was o.k. Today, I ordered a POF roller cam pin to see if that makes the problem go away. Some folks have told me that this isn't unusual and just to shoot a 100 rounds through it and the problem will go away I'm leery of this, but don't know which way to turn. This rifle has never had a live round chambered, at leas since I bought it. So ammo isn't the problem. The barrel and lugs all look good to go. I'm fresh out of ideas, and hoping the roller cam solves the problem, wishful thinking, probably. I'm open to about any suggestion including melting it down for scrap metal. Seriously, any ideas, thoughts or other knowledge anyone could give me would be greatly appreciated. Thanks much, Quote Link to comment Share on other sites More sharing options...
98Z5V Posted March 6, 2015 Report Share Posted March 6, 2015 Shooting it will work out the bugs. These big things are quite different than the little brothers. Shouldn't have any problems after parts are forcefully mated together after 100~200 rounds. Larger caliber semi-auto rifles can be a biotch sometimes. Quote Link to comment Share on other sites More sharing options...
FaRKle! Posted March 6, 2015 Report Share Posted March 6, 2015 (edited) If you've already checked the cam pin track and the cam pin isn't getting held up in there due to poor machining, then just break it in with some rounds like 98 said. Lube it up well when you break it in too. Edited March 6, 2015 by FaRKle! Quote Link to comment Share on other sites More sharing options...
survivalshop Posted March 6, 2015 Report Share Posted March 6, 2015 As has been said , some of the 308 rifles need break in round count to free up the actions . On new built AR's of any caliber , I use a small amount of grease on the rear of the bolt locking lugs & a little on the cam pin . Most will say , no grease in any rifle , well in some conditions , this is a good rule to follow , but a new rifle & having problems , a very small amount of grease will help the action get through the break in cycle , if having a problem like yours . The products I use are , Gun Slick & a Synthetic grease , Red & tacky , but any mil spec rifle grease will work . You don't need much , just a swipe on the back of the Bolt locking lugs & Cam pin, after normal oiling .After a higher round count , you can omit the grease & just use the CLP or what ever your normal lubricant you use . The Gun Slick is a black Graphite looking lubricant & after you cycle the action a couple of times , it looks like you went through a couple of thousand rounds with out cleaning . I have used GS even in very cold temps. , the Red & Tacky would be for warmer environments . Being a Factory rifle the Head Space should have been checked , but its good practice to check it when here is a problem like this , just to be sure its properly set . Quote Link to comment Share on other sites More sharing options...
Fort Tom Posted March 6, 2015 Author Report Share Posted March 6, 2015 Thank you all. I will lube the living daylights out of it, and I have some Shooters Choice (red) light gun grease, I can use with the new roller cam pin. Since it seems the consensus is to shoot a couple of hundred rounds out of it, that's just what I'll do. Lube that thing to near excess and shoot it and see if it "breaks in". Thanks, again, FT Quote Link to comment Share on other sites More sharing options...
survivalshop Posted March 6, 2015 Report Share Posted March 6, 2015 I have one of those roller cam pins & used it in my 16" for a while , didn't notice any difference , but what the hay , check it out , you never know . Quote Link to comment Share on other sites More sharing options...
Fort Tom Posted March 7, 2015 Author Report Share Posted March 7, 2015 You mentioned that the roller pin didn't help, did it do any harm? Just curious. Oh well, wouldn't be the first time I wasted $$ "trying something". Thanks, FT Quote Link to comment Share on other sites More sharing options...
98Z5V Posted March 7, 2015 Report Share Posted March 7, 2015 (edited) It certainly won't hurt, as long as it fits. Anytime you have only smooth-machined surfaces as the bearing surface, and you add a roller to the mix, it's going to cut down on friction, stiction and resistance. In this case, your smooth-machined surfaces are the cam pin body and the machining of the cam pin groove into the bolt carrier body. Putting a roller in there certainly cuts down on that resistance, et al. Since this would be something that would have to be measured, the question would be - does it cut down enough in order to enhance performance? Maybe not. However, will it cut down on wear on those parts, over time? By it's very nature of not have metal slide on metal, it will add to the longevity of those two pieces. Just another way to look at it. P.S. We're currently seeing this for the first time, in triggers. The Elftmann Trigger... Definitely more to follow on that, as time goes on. <thumbsup> Edited March 7, 2015 by 98Z5V Quote Link to comment Share on other sites More sharing options...
survivalshop Posted March 8, 2015 Report Share Posted March 8, 2015 (edited) As far as it hurting , I do see abnormal wear on the back of the Bolt locking Lugs , not sure if its from the Roller of Just a soft DPMS Bolt . I have the Barrel & another BCG ( Shadow Ops Weaponry, NIB, with STD Cam Pin type ) in another Upper ( Tactical machining ) on a DPMS Lower & its had quite a few rounds through it & no signs of any wear at all on the Bolt locking Lugs , but it being in a different Upper Receiver , & NIB Bolt , hard to say if you can even do a comparison . Edited March 8, 2015 by survivalshop Quote Link to comment Share on other sites More sharing options...
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