Rockin308

Well, Sold my Grendel, to fund some more other project items. Going to miss it a bit but got the Lr308 now and the funds of the sale are going towards a 6.5 Creedmore upper. Took the Lr308 out again yesterday it performs perfectly, was getting again 1-1.5" groups at 100+ with steel case ammo the 1" group was with Federal 150 grain JSP. At this time this has to be the one of the my best builds. I've done several AR 9s and Ar15s in different calibers, but this Lr308 is the bees knees. Thanks to all the answers to my Lr308 build questions.

I also updated the trigger, put in a CMC flat face 2-stage match trigger. It's a smooth trigger.

Thanks, I think I got it dialed in, now to shoot the poop out of it. This has to be one of my best builds, my 6.5 Grendel is a good one as well Picture shows the 6.5 Grendel

Yeah, I thought the same thing after she shot it, lol.

Thank you, I have read the same response that you just gave on other forums and from some of my gunsmiths on my gunsmith groups. I had no issues with ejection at all and it was throwing the brass and steel case about 4-5 feet. So, I thank you for confirming that I knew on the large frame rifles, if the rifle is cycling its gtg.

Got back from the range yesterday, and I am impressed with this build. I was shooting 150 Grain Federal JSP and with that 1-8 Swampfox scope at 100 yards was getting 1-1.25" groups. I will say this about Faxton they make same really good barrels. That trigger was really smooth as well, the flat faced trigger your follow up shots are quick and precise. I also shot some 145 grain Steel case ammunition and it performed well. got around 1.25-1.5" group from that ammunition. I don't have the name on that ammunition but for a budget range ammo it was gtg. That Swampfox optic is amazing, and it only took 3 shots to sight it in at 100 yards. I used the Federal for sight in, that is most likely the ammo I will use for deer and hog with this setup. I am not sure about the AFG on the handguard. I tried out that Shooters lube from Springco and I like its performance, stays put and keeps the Lr308 running smooth. Now the only question I would have been what is the standard ejection pattern on a LR308? I noticed at the range yesterday it was ejecting at a 1:30-2:00. I know with AR15s you want it around the 3-4 O'clock location, but I am not sure about LR308. I didn't have any feeding issues with either ammunition. The rifle performed flawlessly, even my fiancé shot it and she liked it. At this time, I am very impressed with this build and would like to thank everyone that helped me along my way. I now have gained knowledge in another platform to increase my gunsmithing skills. I graduated from SDI about 2 years ago and have been working in the firearms industry for just over a year now, and I jump at any opportunity to gain knowledge in the craft. Now my next task is to build an AK 47 here soon. Thank you all, this forum site is my go-to source for anything AR10/Lr308 related. I have a buddy that now wants me to build him one.

Hello all, Well, I got the new Springco spring, new 5.3 oz buffer and the correct gas tube length installed. Now just waiting for the new scope today for the build. Got a Swampfox Tomahawk 1-8x24 on its way today. Found a real light weight mount sitting around that I forgot I had. I have mounts everywhere, since I get one-two each Christmas. Here's the parts list so far. I will post after range report hopefully today. Barrel: Faxon Firearms .308 Winchester Pencil Rifle Barrel | Up to $13.95 Off 5 Star Rating w/ Free Shipping (opticsplanet.com) Handguard: UTG Pro M-LOK DPMS-LR308 High Profile Super Slim Free Float Handguard | Up to $5.00 Off 5 Star Rating w/ Free S&H (opticsplanet.com) Magpul M-Lok AFG grip Muzzle device: Strike Industries Japan Jcomp Type 89 Compensator | $4.00 Off 4.6 Star Rating Free Shipping over $49! (opticsplanet.com) Upper receiver: https://www.opticsplanet.com/aero-apar308503a-308-upper-blk.html Lower Receiver: Aero Precision stripped lower M5 Buffer Kit: https://www.opticsplanet.com/aero-precision-m5-308-enhanced-carbine-buffer-kit.html With, Springco Orange recoil spring and Expo Arms 5.3 oz buffer Butt stock: https://www.opticsplanet.com/mission-first-tactical-battlelink-extreme-duty-minimalist-stock-ar-15.html BCG: https://www.opticsplanet.com/lantac-m-spec-bolt-carrier-group.html Scope mount: Amazon.com : Monstrum ZR300 H-Series V1 Hollow Frame Lightweight Offset Picatinny Scope Mount | 30 mm Diameter : Sports & Outdoors This is what I got last Christmas, yes, I know it's cheap, but it has been on several rifles with other scopes and the weight is only 4.3 oz. Scope: https://www.opticsplanet.com/swampfox-tomahawk-1-8x24-lvpo-riflescope.html Trigger: AR15 and AR10 drop in replacement flat trigger | lighten trigger pull | reduced power spring | AR15 | AR-15 | AR10 | M16 | enhanced fire control group (taylor-tactical-supply.com) Grip: Magpul Industries AR Rifles MOE-K2+ Grip | Up to $1.25 Off 4.9 Star Rating Free Shipping over $49! (opticsplanet.com)

I really wish I went with my gut on this build, was goin to just get the enhanced Aero buffer tube, the Springco Orange spring and the 5.3 oz buffer. Also, was going to order both size gas tubes, Armalite and stand rifle. Guess from now on I'm following my gut, and listen to your fellow brother's in arms. Buddy told me a few month before I started this build what to get, now he's giving me a big,.I told you so.

I knew that this Lr308 build was going to be a learning experience, glad I discovered this forum and your experience with this platform. Thank you

Okay, Again, thanks for the info.

Now, I discovered a #41 drill bit is 0.096" can I drill it out to that diameter and still be gtg? Currently drilled out to 0.0945 would like that extra bit.

No just not passing the gas ring test, the rifle functions but yes still needs the correct buffer and spring.

I do agree, I beating a dead horse by not test firing with the correct buffer system. It's just the condition the Lantac M-Spec BCG is in after only 40 rounds. The gas rings failing the test, I don't like one piece gas rings never had any luck with the on any AR/Lr platform. Thank you all for the information this is my go to forum for anything Ar10/Lr308.

I am awaiting the Springco Orange spring and 5.3 oz buffer, I just test fired it with the new gas tube to see if it would lock back after a few rounds fired, which it did. Now about the gas ring, when preforming a gas ring test, BCG assembled and bolt extended fully it falls down when stood up on the bolt in the carrier. It supposed to not fall under its own weight. This happened after only 40 rounds through the BCG.

Well, After drilling the gas port to .0945" and installing a Armalite Rifle length gas tube, it cycles, well kinda. I got some strange failures, each time it was like the extractor wouldn't let go of the casing, this happened about 3 times, so I took out the extractor and removed the o'ring donut from the extractor spring, then refired the rifle this time it happened about every 5-8 rounds. When inspecting the extractor (will post pics later) could see slight deformation of the extractor claw. Also, discovered that the Lantac M-Spec BCG I got has a one piece gas ring, which I've never had any luck with even on AR 15s. So I'm going to replace it with the standard 3 rings. I also replaced the bolt catch it seems to be hanging up on the original bolt catch from the Aero Precision M5 lower receiver kit. I put a bolt catch that looked like an Ar10 type. Still need an Orange Springco spring and a 5.3oz buffer. Any suggestions on what could have been causing the malfunction, why the extractor wasn't letting go of the casing? Was using Sellier and Bellot 7.62x51 and PMC brass 308 Winchester.

Thank you all, I have never used those style of buffers before. Just the good old Mil-Spec ones for an AR 15. When I get home I'll take better pics and turn it in one more turn. Thanks again.

measured the gas port size, I got .093" gas port I've been considering drilling it out slightly more but would like to just try the new longer gas tube first. I have a new gas block coming got at Superlative Arms adjustable gas block on it way as well. Thanks for the information I've been reading all the info on buffers and gas port sizes and gas blocks, everything about tuning in your Lr308/Ar10 build. Well I just went and done it, remeasured the gas port and I was wrong on my first measurement statement, the .093" was my buddies barrel that I wrote down his gas block measurement, I just thought it was mine, when I remeasured the gas port on my barrel it was .090" I found a drill bit that was .0945" and went with that, since this was the only drill bit in my arsenal of drill bits that came close to the .095" mark.

measured the gas port size, I got .093" gas port I've been considering drilling it out slightly more but would like to just try the new longer gas tube first. I have a new gas block coming got at Superlative Arms adjustable gas block on it way as well. Thanks for the information I've been reading all the info on buffers and gas port sizes and gas blocks, everything about tuning in your Lr308/Ar10 build.

Hello, I am not familiar with these type of buffer tubes with the notch cut extension for the buffer retaining pin to snap into. Now is this far enough or do I need to turn it in just a bit more? Thank you, Rockin308

Hello, New here just built my first LR308. Here is the parts listing. Aero Precision M5 Upper and lower receivers with Aero Precision M5 lower receiver kit Aero Precision M5 Enhanced Buffer kit complete Faxon 18" rifle length gas, with Aero Precision gas block and rifle gas tube, (did notice when assembled the gas tube wasn't in the middle of the cam pin cut out in the upper receiver) Strike Industries J2 Comp brake UTG Pro 15" 308 handguard Lantac Mil-spec 308 BCG Ambi charging handle (had this laying around not sure of manufacture, will replace asap with either and Aero or Strike Industries) MFT Battle link Extreme Minimalist duty stock So far on the first range visit the rifle wouldn't cycle correctly, wouldn't hold back after just firing one round in the magazine. This is my first rifle length gas system build in any of the AR/LR 308 platforms, so I think and from what I have read on this wealth of information forum that the gas tube is too short. I don't think it was the gas block in any way I used the Kak dimple jig to put one dimple in the barrel matching up with the gas port. I installed the gas block without the gas tube and used a piece of weed eater cord to see if I had correct alignment and I did. So again, I am thinking it's the gas tube length being too short, the Aero Precision gas tube I got did state rifle length but is only 15.25" in length, I think the Armalite 15.5" is what it needs too properly cycle. The buffer system is the Aero Enhanced buffer tubed with their 308-recoil spring and the 3.8 oz buffer, I want to get it functioning with this setup first then try perhaps the orange Springco spring and a Kak 5.3 oz buffer. If any of you 308 gurus have any other possible suggestions, please share your knowledge. Thank you for the join up on this information superhighway, Rockin308