Jump to content
308AR.com Community
  • Visit Aero Precision
  • Visit Brownells
  • Visit EuroOptic
  • Visit Site
  • Visit Beachin Tactical
  • Visit Rainier Arms
  • Visit Ballistic Advantage
  • Visit Palmetto State Armory
  • Visit Cabelas
  • Visit Sportsmans Guide
Nimravous

DPMS LR-308. First time customizing failed.

Recommended Posts

  • Hello all.  
    I’m new to the group. I have lurked online for a while. I decided to change some things on my DPMS carbine LR-308. I bought a Samson m-lock forearm, and changed the adj stock to. Magpul MOE fixed stock. I went with an Argo low profile adjustable gas block. I did not realize that I needed a different buffer tube. When I did I bought one of those as well ,an AR stoner extreme duty buffer assembly. It came with a new spring and buffer. All parts came from midway all were marked LR-308 compatible   I went to sight in today and the gun will not cycle. When fired a bullet will not eject, it gets stuck about halfway. I can cycle it back and it ejects properly, and loads another round. No bolt catch on empty mag.  I have read so many threads on the internet  that I am completely confused. Im thinking either the spring/buffer is off. I’ve read about making sure bolt is oiled may be an issue. It is maintained properly.  Gas rod etc...  don’t really know where to start. If my parts are poop, I’ll replace, I just want it to work as designed. Main use us hunting. I’m shooting hornady 150gr interlock, they worked before the changes. 
    A little background on me.  I have worked in firearms sales/repairs for 16yrs. But that was after the 90’s ban and I was out before AR’s we’re a huge thing. In my area anyway, that I could afford anyway.  I left in 2005 and this is my first time doing work like this. I feel I have a pretty good base knowledge on shotguns and bolt guns, but this style is new to me.  I own several but all have factory modifications.  I live in rural south east NC.  At least an hours drive from a decent gun shop and probably 1.5-2hr on a competent gunsmith.  No friends in my circle with any knowledge on this. Any help on this matter would be greatly appreciated. It’s probably my own ignorance , but I’m trying to learn and feel this is the place to seek answers. 

6C581235-54E2-44F1-8D61-79CABF5BF35E.jpeg

Share this post


Link to post
Share on other sites

Can you manually lock the bolt back?  You didn't mention - did you try to adjust the gas block?  Sounds like you need to open it up (adjust for more gas).  Most of the adjustable gas block instructions tell you to increase gas until you get the bolt to lock back on a magazine last round and then turn the adjustment one more click to ensure gas is sufficient for all ammo.  If that doesn't work, is your gas block lined up with the barrel's gas port correctly?

Share this post


Link to post
Share on other sites

I can lock it if I press it in by hand. I did check when I assembled it to make sure the holes lined up and from what I have researched it looks to be seated correctly. I need to study some more on the adjustable aspect of the gas block. I was a little too excited when my parts came in and assembled it about 11:30pm outside via headlamp, vice is on my service truck, and had to wait 4 days to shoot. I’ll check these things out.  Thank you for giving me a starting point. 

Share this post


Link to post
Share on other sites

So the brass is stove piping? Do you have pictures of the malfunctions? 
 

Also I can’t find any specifics on your buffer spring and buffer. How much does the buffer weigh, how long is your spring and how many coils? Getting that information usually helps some of the smarter guys rail out your buffer assembly. 

Share this post


Link to post
Share on other sites

Not stove piping exactly, it’s extracting  the brass just not ejecting. It is getting hung about halfway back.  After the first reply I watched a video on the adjustable gas block and I’m 99.9% sure that’s my problem. I was too excited and put it together about 11:30pm outside via headlamp, vise is on my service truck. The video I watched to install must have been a fixed block because the guy never addressed it. Also, I’m a throw the directions away kind of guy, that’s usually my way of learning how things work. I’ll get it adjusted and see . Sorry for being so much of a noob. I am alone with this kind of stuff and really appreciate all the help. It will be a few days before I can shoot again but if the problem persists I know where to go. 

Share this post


Link to post
Share on other sites
2 minutes ago, Nimravous said:

About 3 hours give or take. I’m about 10miles from the south of the border Sombrero on I95 south. 

Might have to give you a shout on one of my Oak Island ventures.

Share this post


Link to post
Share on other sites

I go to Caswell beach when I can. I’m a farmer, and deal with poultry, and COVID has got the industry all jacked up.  High demand low manpower.  Haven’t been in a month. Starting to have withdrawals. 

Share this post


Link to post
Share on other sites

The gas block may very well be it. But for prosperity please measure and weigh buffer components. Also, I will warn you making friends with matt cross may cause Coca Cola addiction or an empty wallet. You’ll have a good friend, but one or both may ensue!

Share this post


Link to post
Share on other sites

Haha. I will do just that. It will be a while before I can do that but I’ll make sure to post. 
I am a Texas born Kentucky/NC raised army brat with an affinity for all things that cut, shoot, and go boom. So any like minded people are good in my book. 

Share this post


Link to post
Share on other sites
39 minutes ago, Nimravous said:

Haha. I will do just that. It will be a while before I can do that but I’ll make sure to post. 
I am a Texas born Kentucky/NC raised army brat with an affinity for all things that cut, shoot, and go boom. So any like minded people are good in my book. 

Welcome Nimravous, an Air Force Brat born in Fayetteville, unfortunately now imprisoned in "Central Obamastan"!

Share this post


Link to post
Share on other sites
8 hours ago, edgecrusher said:

 Also, I will warn you making friends with matt cross

^^^^ This is never bad advice. :lmao:

And it definitely sounds like a gas block and/or recoil issue.

Share this post


Link to post
Share on other sites
8 hours ago, shooterrex said:

Open the gas block all the way up. Then close it a little at a time till it won't lock the bolt back on a empty mag. Then open back up just a bit.

^^^ This is how one should set up every single adjustable gas block out there.  You START by running it wide open, and close it down until it doesn't lock back.  Not the other way.

Share this post


Link to post
Share on other sites
9 hours ago, 98Z5V said:

^^^ This is how one should set up every single adjustable gas block out there.  You START by running it wide open, and close it down until it doesn't lock back.  Not the other way.

We can agree to disagree.   

What about adjustable gas blocks that have suppressor bleed off positions past the "wide open" gas position?  On a non-bleed off adjustable gas block, where do you stop when you back the metering screw out to run it "wide open"?  As I said, most instructions tell you to start from the closed position or 1 turn open from the closed position and this is good advise for the questions I stated above.  The OP wasn't getting the bolt to lock back so there is no reason for him to go to the gas block closed position to start the tuning process.  Just start from where he's at and open it up a little at a time. 

Either way, you get to the same end. 

Share this post


Link to post
Share on other sites
15 hours ago, BIGTRUCKNUT said:

We can agree to disagree.   

What about adjustable gas blocks that have suppressor bleed off positions past the "wide open" gas position?  On a non-bleed off adjustable gas block, where do you stop when you back the metering screw out to run it "wide open"?  As I said, most instructions tell you to start from the closed position or 1 turn open from the closed position and this is good advise for the questions I stated above.  The OP wasn't getting the bolt to lock back so there is no reason for him to go to the gas block closed position to start the tuning process.  Just start from where he's at and open it up a little at a time. 

Either way, you get to the same end. 

You open the block all the way up to whatever the manufacturer states is the max open position.  Keep in mind, you're never, ever going to pass more gas the further you open it up - than your gas port in the barrel will allow. 

Look at it this way - if you start fully closed, and open incrementally, how will you ever find out if your gas port in the barrel is big enough in the first place?...   If your gas port is too small to start with, you'll waste a big handful of ammo, and still not know that the gas port is too small. You'll just think that the expensive gas block that you bought - doesn't work.

If you start with it wide open - and that first single round doesn't lock the bolt back, with max gas?   You know right then, with that very first round, that your gas port is too small... 

That's why you start with them wide open, right from the get-go...

Share this post


Link to post
Share on other sites

Alright, alright, alright. Gas block it was. Rifle is functioning beautifully. Took out some of the old lady’s porch pumpkins since I’ve worked on Christmas decorations for the last 4 days after work. I started off at where it was was and backed out until I was golden. Thank you all for your help on this matter. Honestly for the last couple of days I’ve just been reading other boards trying to learn more. Makes me want another one. I’m liking the 6.5.  Anyway, Thanks so much. 

Share this post


Link to post
Share on other sites
On 12/1/2020 at 10:58 PM, 98Z5V said:

You open the block all the way up to whatever the manufacturer states is the max open position.  Keep in mind, you're never, ever going to pass more gas the further you open it up - than your gas port in the barrel will allow. 

Look at it this way - if you start fully closed, and open incrementally, how will you ever find out if your gas port in the barrel is big enough in the first place?...   If your gas port is too small to start with, you'll waste a big handful of ammo, and still not know that the gas port is too small. You'll just think that the expensive gas block that you bought - doesn't work.

If you start with it wide open - and that first single round doesn't lock the bolt back, with max gas?   You know right then, with that very first round, that your gas port is too small... 

That's why you start with them wide open, right from the get-go...

Maybe, just maybe it is a good idea to measure the gas port before you buy and install the new high dollar adjustable gas port. (98 has posted the sizes of gas ports for almost every situation you might encounter)

It is kind of like getting drunk, If a half pint of whiskey don't get you drunk, it don't do any good to divide up a new half pint with a shot glass the next time, just go ahead and buy a full pint and see if it does the job.  knock your self out!

Share this post


Link to post
Share on other sites
On 12/2/2020 at 5:27 PM, Nimravous said:

Alright, alright, alright. Gas block it was. Rifle is functioning beautifully. Took out some of the old lady’s porch pumpkins since I’ve worked on Christmas decorations for the last 4 days after work. I started off at where it was was and backed out until I was golden. Thank you all for your help on this matter. Honestly for the last couple of days I’ve just been reading other boards trying to learn more. Makes me want another one. I’m liking the 6.5.  Anyway, Thanks so much. 

Glad to hear that adjusting the gas block worked for you - regardless of technique used.  Yes, these things are habit-forming!

Share this post


Link to post
Share on other sites

In addition to running a lot smoother, the adjustable gas block made a big difference on what my used brass looks like - for reloading (no more swipe marks from the ejection pin).  Another really nice change was the Gen 3 Little Bastard Self Timing Muzzle Brake my son got me for fathers day.  The people next to you at the range aren't going to love it, but you'll appreciate not having a sore shoulder/bruise after spending a day at the range turning $ into noise.

Share this post


Link to post
Share on other sites
On 12/4/2020 at 10:05 PM, sno4fun said:

In addition to running a lot smoother, the adjustable gas block made a big difference on what my used brass looks like - for reloading (no more swipe marks from the ejection pin).  Another really nice change was the Gen 3 Little Bastard Self Timing Muzzle Brake my son got me for fathers day.  The people next to you at the range aren't going to love it, but you'll appreciate not having a sore shoulder/bruise after spending a day at the range turning $ into noise.

Go make an Intro post in that section, and tell us the details on your gun.  Same section that you made your first post in, but make an actual Intro about you.  Love to hear the details on the gun parts used in your build.  :thumbup:

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...