Help with a Mega Maten

[Jcunning19]

Hey everyone new guy here, i just swapped for a Mega Maten build with a guy. I have a few questions being this is my first Non factory rifle ever i inspected the rifle when I purchased it being Inwas in the army 14 years I’m quite knowledgeable on parts etc and things to look for on factory rifles but it’s is a entire new animal. . First a little info on the rifle

1. the previous owner Purchased it from a dealer said it ran great and shoots excellent However it does not and I can’t get ahold of the guy. Go figure.

2. I’ve been getting failures with the bolt not feeding rounds into the Chamber. Seems like a magazine issue, however sometimes it’s hard to manually eject a round, as in pulling the charging handle. It’s better with Pmags but gets worse with DPMS mags. Seems to fire okay with the pmags but had a double feed on the 3rd shot. 
3. The Barrel is a Rainier Arms, not sure which model though seems like a medium barrel 18”, i can’t find it on their website, not sure of the Bolt brand either, has a rubber insert on ejector instead of spring,  single stage milspec trigger, unsure of brand,

the main question I have is the Bolt being a little hard to pull back only when rounds are fed, could this be a headspace issue? The bolt cycles very smooth otherwise.

second question is should I order a Rainier arms Bolt Since I have no clue what brand this bolt is? Could that fix my problem with feed issues.  
i added some pictures as well. I really thought it was a fine rifle when I checked it out. Everything seemed excellent t in the build quality.  Any help or insight would be greatly appreciated. 
 

 

[Anderson3754]

I'll try to help

Question #1

Are you using factory  ammo or reloaded ammo. If factory ammo what brand. 

[Jcunning19]

Yesterday I shott some Barnes Vortex through it. It cycled the first two shots then double fed due to the shell not extracting all the way etc. 

i also tried to cycle some other cheaper American eagle reloaded surplus through it. Both seem to cycle the same. I’ve been cycling it as in charging the handle manually and then ejecting a shell etc. with the American eagle trying to tweak the mag lips on the DPMS magazine, the 6 rounds I fired from it were the only time so far that I had the double feed issue where one round Wich was fired didn’t eject all the way and it fed another during that cycle. Hopefully that makes sense. I did check the feed lips on the mags as well. They seem fine.  The only thing I notice is that when the bolt is charged all the way to the rear it seems to be to far forward in my own judgment. But I could be wrong. It barely clears the last shell Wich could be a link with the bullets not feeding all the way.  After writing all this. The dam rifle sounds like a train wreck

[Armed Eye Doc]

I'll start with a few common issues.

What is the interior depth of your buffer tube?

What is the length and weight of the buffer?

Do you have a picture of the bcg travel limitations?

While we're at it, how far does the gas tube provide into the upper?  A picture straight up through the magwell will show whether that needs changing.

 

[Jcunning19]

I will take some pictures when I get off work and take some measurements. Should be around 1530 when I get it all done. 
Thank you! 

[Armed Eye Doc]

23 minutes ago, Jcunning19 said:

I will take some pictures when I get off work and take some measurements. Should be around 1530 when I get it all done. 
Thank you! 

[Anderson3754]

1 hour ago, Armed Eye Doc said:

I'll start with a few common issues.

What is the interior depth of your buffer tube?

What is the length and weight of the buffer?

Do you have a picture of the bcg travel limitations?

While we're at it, how far does the gas tube provide into the upper?  A picture straight up through the magwell will show whether that needs changing.

 

1 more to help..  Does it have an adjustable gas block ?

[Jcunning19]

Negative on the adjustable gas block

[edgecrusher]

5 hours ago, Armed Eye Doc said:

I'll start with a few common issues.

What is the interior depth of your buffer tube?

What is the length and weight of the buffer?

Do you have a picture of the bcg travel limitations?

While we're at it, how far does the gas tube provide into the upper?  A picture straight up through the magwell will show whether that needs changing.

 

This. To me not knowing your parts manual I’d start with recoil system. Just by your description it sounds like it is most likely incorrect.

[Jcunning19]

I attached lengths etc in pictures.  I’m assuming the D stamped on the Bolt is DPMS and the D 10 on the barrel is DPMS.  

[Jcunning19]

I have no idea the weight of the Buffer.  There is no manual with it, nothing.  So I’m hoping I got a decent deal after I work this bug out of it. I swapped a Alexander arms .50 Beowulf for it. 

[Matt.Cross]

Just now, Jcunning19 said:

I have no idea the weight of the Buffer.  There is no manual with it, nothing.  So I’m hoping I got a decent deal after I work this bug out of it. I swapped a Alexander arms .50 Beowulf for it. 

The good news is that 95% of your kit is really good kit. At most a spring, buffer, or gas port upsizing will get you sorted out. You're probably close enough to me we could get together and work through it.

[Jcunning19]

I’m in Maggie Valley NC.  That’s good to know. The guy I got it from promised it would shoot 1moa at 100. So eventually we will see. I just want it to be right before I go to the range and look like a dumb ass. Haha

[edgecrusher]

13 minutes ago, Matt.Cross said:

The good news is that 95% of your kit is really good kit. At most a spring, buffer, or gas port upsizing will get you sorted out. You're probably close enough to me we could get together and work through it.

This guy knows his stuff, and at the very least, the two of you can shoot off and get a few mils. (Inside joke here, not at your expense). Your buffer appears correct but no your receiver extension. (Buffer tube) That should have a measured internal depth of 7” for that buffer.

[Armed Eye Doc]

2 minutes ago, edgecrusher said:

This guy knows his stuff, and at the very least, the two of you can shoot off and get a few mils. (Inside joke here, not at your expense). Your buffer appears correct but no your receiver extension. (Buffer tube) That should have a measured internal depth of 7” for that buffer.

That is what it looks like to me.

[Jcunning19]

Also. It’s right at 7 on the buffer tube itself. The camera angle must effect it. I remeasured because I could have sworn I got 7

[Matt.Cross]

Just now, Jcunning19 said:

Also. It’s right at 7 on the buffer tube itself. The camera angle must effect it. I remeasured because I could have sworn I got 7

You're well within the margin of error. It's possible your chamber is slightly tight and could just do with a bit of light polishing. The double feed is entirely a magazine issue, not hard to fix that. My money is on your recoil spring.

[DNP]

How’s it do with just one round in the mag?  You said it’s hard to manually eject a round -unfired?  Try loading one in and then stripping the mag out. Feel the same to manually exert at as it does with the mag inserted?  Just thoughts. 

[Jcunning19]

It feeds fine with just a couple of cartridges in it. It only gets real tight on a half mag or full mag.  
 

matt what Spring for the buffer tube would you suggest? Also would I be alright ordering a Ranker arms Match Bolt for it instead of the plain DPMS BCG 

[Jcunning19]

Would the orange spring solve my problem

[Matt.Cross]

50 minutes ago, Jcunning19 said:

It feeds fine with just a couple of cartridges in it. It only gets real tight on a half mag or full mag.  
 

matt what Spring for the buffer tube would you suggest? Also would I be alright ordering a Ranker arms Match Bolt for it instead of the plain DPMS BCG 

BCG isn't your problem. It's good kit. The mag issue is telling the story on what's happening here. The right recoil spring will send the BCG into battery regardless of how full the mag is. This could also account for part of the feeding problem.

Don't change more than one component at a time, you'll quickly get lost as to what's actually the component at fault.

[Jcunning19]

10/4 I will start there. Thanks man! I really appreciate it. 

[Matt.Cross]

1 minute ago, Jcunning19 said:

10/4 I will start there. Thanks man! I really appreciate it. 

Here's what I've been using in my Mega Arms for almost 10 years now....

http://www.davidtubb.com/bufferspring-sr-ar10

[Jcunning19]

I will order one. Thank you for your help. 

[Matt.Cross]

25 minutes ago, Jcunning19 said:

I will order one. Thank you for your help. 

No problem, if it doesn't fix your problem or at least work better, I'll buy it from you and pay the shipping. I can use it for a spare if it doesn't help you.