Stubbie68

Just thought I would check back in. Like I mentioned previously, replaced the spring with the heavier flat spring that was recommended by jtallen83. Also, shortened the buffer by a sixteenth. Double checked the gas block and put it all back together. Took me a while to get back to the range. After some minor adjustment to the gas block screw it seems to be running perfectly. Locks on the last round and chambers consistently. Put another 50 rounds down range with no jams or failures. Shot groups weren't bad but not great either. I'm sure there will be a breaking in period and the ammo I was using was cheap brass reloads so it's to be expected. One more trip to burn up my last 50 of reloads then I'll work on load development with some better brass and a few different powders. Does anyone have a "pet" load that seems to work well? Anyway, I would be remiss if I didn't say thank you to all the folks that provided input and guidance. I really do appreciate it.

Ordered!! And the buffer has been shortened by 1/16" I also pulled the gas block and verified the distance from the shoulder to the gas port on the barrel and the distance from the edge of the gas block to the hole for the gas tube. They line up perfectly now. They were not perfectly aligned before. I'm smellin' somethin'!!

I understand. Trimming the pad won't be a problem. I have been searching for a spring that matches the specs mentioned but I'm having a lot of trouble. Most sites I looked at just say what it's for but don't list the specs. Any suggestions?

No disrespect intended and maybe I am reading this wrong. Actual length of the buffer was 5 5/16. That is a lot closer to 5.2 than it is 5.9. The latter would be like 5 13/16. Is that not correct? At 5 5/16 that is 1/16 greater than 5 1/4 or 5.25.

The buffer itself is just a hare shy of 5 5/16. So almost 1/8 longer than was stated it should be. What about the spring? Replace both? Anyone have a link to the correct combination? I should also note that I can manually lock the bolt to the rear with the current length buffer and there is additional travel beyond the locking point. Not much but it is there.

This is the exact buffer, tube and spring combo I purchased from Guntec. Unfortunately none of the specs are listed on their website. https://guntecusa.com/product/ar10-lr-308-rifle-stock-tube-kit-308-cal/ My dies, and bullets are in the mail on the way here. If I am going to burn ammo trying to get this thing "broken in" I will do it with cheap stuff. I will reload a few hundred and use them. 150 gr. Hornady FMJ should do the trick. I have primers and powder already so I will load them up to average velocities. I could try a couple hot loads to see if that helps.

Okay, here is what I have so far. Buffer weight 5.5 oz. Buffer tube depth 9 5/8" Spring wire diameter .081" Spring relaxed length (as soon as I took it out of the rifle) 12" meaning it might relax more after sitting a while. Don't know. Spring coil count 38 Spring is polished or stainless, don't know which, I am guessing stainless

Only fired 20 rounds. Have to admit was a little frustrated. Had to pull the charging handle back on every round. BCG was oiled up well. Gas block was wide open at the end after I tried adjusting with no change.

Just measured the spring and weighed the buffer. Buffer is 157 Grams or 5.5 ounces. Spring is pretty stiff and has 36 loops. I checked the travel in the tube and pulling the charging handle all the way back the bolt face is not in contact with the bolt catch. There is a short distance between the bolt face and the catch when fully to the rear so nothing physical is impeding travel to the rear and it goes physically back far enough to work properly.

So I finally made it out to the range today. Didn't go well. I will try to give as much information as I can. Bottom line is, in my best guess, it is either one of 2 things. Buffer is too heavy (mass) or spring is too stiff or something is wrong with the gas system. I have an adjustable gas block and it functioned exactly the same from when I started (first round) to when I adjusted it all the way out. The bolt is not going all the way to the rear. Not cycling correctly. I tried one round at a time to make sure it was ejecting at 3 o'clock and the bolt was locking to the rear after the last round. The bolt does not travel back far enough to lock and while it does strip the next round from the magazine (sometimes) it does not have enough force forward to lock the bolt onto the back of the round. In other words it will not go into battery. With multiple rounds loaded in the magazine I had to drop the magazine, pull the bolt all the way to the rear (the round that was stripped remained in the chamber) and let it slam forward from the full open position to lock the bolt into battery. I am guessing the buffer is too heavy and/or spring too stiff. At least that is what I hope it is since it's an easy fix. Hope it's not the gas system. Any suggestions on a better way to trouble shoot or how to narrow it down? Thanks in advance.

These are an over run and according to Faxon do not have the notches for the forward assist and will not work with a 2 stage trigger or full automatic. Why that would be an issue I don't know. Thought it was a good price so i put it up here. https://faxonfirearms.com/oem-overrun-ar10-nitrided-bolt-carrier-group/

I am in the Fredericksburg area. Spotsylvania to be exact. As I read above I do go to Clark Brothers but not my favorite place. Not many other options though. There is "The Range" on Route 1 but only open to smaller calibers. I tend to lean towards the "Holy poop that's big" type of calibers so... Anyone knows a better place to go please let me know. I'm not keen on Quantico but I will if I have to. Retired military and would prefer to keep my distance if I can. I have my reasons but nothing serious. Just a preference. Anyone down to meet up and throw some freedom seeds downrange let me know.

So I thought I would update the post. I finished putting everything together. I had to fabricate a wrench to fit the ballistic advantage heavy barrel nut so I could torque it to spec. The hand guard I ordered is too short and the gas block sticks out. Not a huge deal and I'll order a longer one from the same manufacturer at a later date. For now it's together and ready to test at the range. Just need to find the time. AR Trooper and Cliff R, you guys were spot on. This pig is heavy. I don't mind it much as I won't be walking around with it much but I wanted to give you props for warning me. Anyway, more to follow once I get to the range and tune the gas system and sight in the scope. Happy holidays everyone!! And a safe Blessed New Year!!

I very much appreciate the comment. Transporting it will be the only weight concern. I'll be shooting from a bench or bi-pod. I want the extra length to squeeze as much velocity as I can get. Long distance accuracy is what I want most. From my experience it's about 70 to 80 FPS per inch of length. At least that is what the average seems to be with a traditional bolt action. Not sure if it is the same for the AR platform. Either way it's already purchased. Thanks for your comment!!!

Thank you!! That's the stuff I am looking for. Will do. Jam-o-matic is no bueno.