Help with M5E1 Aero Precision Build

[BUmmedic]

 

   7" is correct for a std AR 15 Receiver Extension ( Buffer tube ) & is used for DPMS type Carbines.

  3.8 oz. Buffer is a little Heavier than the ones I have , but a good thing .

 2.5" is correct for a DPMS Carbine length Buffer

27 coils are two less then the normal 29 coils I have here with two Springs , but may be the way you counted . If the coil count is correct , the less coils may be an issue .

11 1/4 " spring length is correct for a DPMS Carbine Buffer spring .

      I don't see what Gas system length you barrel has . It could make a difference , a Carbine gas system could cause a faster & longer Gas signature . The slight touching at the Extension headed area on the Lower Receiver could also be how the Receiver is made .

   If Buffer spring actually has only 27 coils , I would see if you could get another one to try , it doesn't take much to unbalance the system , if you are compressing the Buffer material on the end of the Buffer that much , that is a problem & stacking $$ in there is just putting a bandaid on to fix a larger issue with the Buffer system . 

 If a New Spring doesn't take care of it , there is a a Company that is on this sight ' Heavy Buffers " who you can get a Heavier Buffer & his cut down AR 10 Spring that will should help slow the BCG down to stop it from hitting the Receiver.

Thanks for all of the excellent info... I will post a pic of my spring the next chance I get. I may very well be counting the coils incorrectly, but from what I have read about coil counting (yes, I looked it up), then it may actually be less than 27. Does the material at the end of the buffer actually compress? Read somewhere about Sprinco springs (the ORANGE one, in particular)... found a couple forum threads that made me question its utility... "flavor of the month" was a term I read. Oh well, I'll post a pic of my spring and maybe it really is a couple coils short despite the length being ok. 

[unforgiven]

Hey isn't 50 cents bankrupt ?? BWAHAHHAHA

Brother I changed the extention,spring and buffer to the Armalite system on my M5.Done.

[BUmmedic]

Well, due to the abnormal wear on the lower and upper, it looks like Aero may want it back for warranty/repair, so I'll let you all know what they say. I'm waiting for CS to respond to my open ticket. 

[unforgiven]

Good luck brother,let us know how this plays out.One of the other guys here was having problems with the recoil system,hence the quarters in the extention tube.In changing to the Armalite system I found out that 1 Armalites extention tube was longer,spring was longer and buffer was longer and heavier than Aero's.When I called Aero tech support and told them the problem and fix he said he was unaware of issues of this type.On this fourm the recoil system has come up a few times.

[BUmmedic]

What have I gotten myself into? :-P

[BUmmedic]

Honestly, for the price I paid for all the parts, I can't complain, but I guess for extra I could have tried to get the peace of mind of a factory build, but I've seen bad stuff happen with those, too. At least I'm learning a ton by riding this wave...

 

Edited February 24, 2016 by BUmmedic

[Dane Armory]

Hey isn't 50 cents bankrupt ?? BWAHAHHAHA

Brother I changed the extention,spring and buffer to the Armalite system on my M5.Done.

No ...  50 got shot ! Not broke.

Look for  DPMS or Armalite 308 spring.

[Dane Armory]

We've seen this before. The quick fix is to stack however many quarters in the bottom of your buffer tube it takes to keep the bolt carrier from making contact with the receiver. Problem solved!

This works great on ar15 pistol builds not so much on big boy ar's. You need a 308 buffer spring.

[survivalshop]

  Also , Tubb's  Flat wire spring could also fix it , The one I measured with my cut out Receiver Extension , showed that under complete compression , the Buffer will not hit the bottom ( or end ) of the Extension , a condition that won't happen with this Spring , so that may also take care of your issue. The same spring is used for Carbine or Rifle . I took mine out of my Carbine to try it in my 18" Rifle stocked 308 . 

   A Black Magic Marker will cover the marks in the Receiver so you can test it . Swiping out for AR 10 Components will also work , as has been said .

 http://www.davidtubb.com/tubb-springs

Edited February 25, 2016 by survivalshop

[BUmmedic]

  Also , Tubb's  Flat wire spring could also fix it , The one I measured with my cut out Receiver Extension , showed that under complete compression , the Buffer will not hit the bottom ( or end ) of the Extension , a condition that won't happen with this Spring , so that may also take care of your issue. The same spring is used for Carbine or Rifle . I took mine out of my Carbine to try it in my 18" Rifle stocked 308 . 

   A Black Magic Marker will cover the marks in the Receiver so you can test it . Swiping out for AR 10 Components will also work , as has been said .

 http://www.davidtubb.com/tubb-springs

Read up on them... will probably be the first thing I'll try once I hear back from Aero. Thanks!

[BUmmedic]

Here are some additional pics. First are buffer and spring, now that I look at it, maybe 26 coils (if I'm even counting correctly). 11.25" long. Buffer 2.5" and 3.8 oz. Other pics show spring out, buffer in, and carrier placed on top and bottomed out. Shows clearance between carrier and receiver. So unless the buffer end is impacting the tube and compressing, there shouldn't be impact between the carrier and lower. 

[survivalshop]

  First off that spring has some funny curves to it , it should lay straight when at rest like that . Its has 26 coils , the way i count . Get another spring for a 308 Carbine to replace it . Tube's Spring is a good choice.  

 The 308 cartridge has a lot of recoil power & that buffer material at the end of the Buffer , is there for just what it says , but that is an extreme condition & with a proper set up Buffer system , a Balanced Buffer system should not be slamming into the bottom of the Extension .

  I was trained to pull the Charging handle , be it an M14 or M16 , all the way back till it stops & then let it go . That is the the only time the Buffer should hit that hard on the Bottom of the Extension .

  Balancing of the system can be done in many ways , Spring tension , Buffer weight & in some AR 15's , changing to an M16 Bolt Carrier if the rifle has an AR 15 Bolt Carrier , which is lighter . Having the wrong components doesn't help the issue .

  Think of the Buffer hitting the bottom of the Receiver Extension every shot , that constant beating will damage the Buffer , Spring ( because its not just reaching its full compression , but compressing past it ) & the Receive Extension its self , its only threaded with Aluminum threading . Felt recoil & vibration will also be increased by the Buffer hitting hard every time .

  My testing has shown, to me any way, that if the Buffer does touch the end of the Extension , its barely enough to leave a slight making on a white piece of paper set in the bottom .  There is a outline of the Buffer on the front side of the paper , but no imprint on the back side of the paper & yes this is from a fired 308AR with Fed. M 80 Ammo.

(front of paper facing the Buffer) Notice how the Spring imprint can be seen on both sides .

( Underside of paper) Marks on the outside is from the Buffer Spring .

 Yes I cut this out & fired the Rifle with it this way .

  

[unforgiven]

DSG got Armalite parts back in stock : https://dsgarms.com/recently-back-in-stock?pagesize=36&pagenumber=2

[shazam]

I would like to know about aero response. i have a BCG from them and have had trouble with my rifle so please fill us in. Personally i think my rifle is just a princess and only likes certain ammo

[BUmmedic]

It's been all quiet for a bit now... I have an open ticket without response regarding the BCG and receiver wear. I have a Tubb spring coming this week, but it'll be a bit before I have a chance to test it out. I'm hoping that helps. As others have said, it seems to run fine, and maybe I'm making a mountain out of a mole hill. 

[survivalshop]

I would like to know about aero response. i have a BCG from them and have had trouble with my rifle so please fill us in. Personally i think my rifle is just a princess and only likes certain ammo

  Try a different complete Bolt .