Under gassed AR 10

[David Thompson]

I have a Daytona Tactical AR rifle kit that I built. It is under gassed. On inspection,  I discovered that it has a 7” long buffer tube,  a 2 1/2”buffer that weighs 3.8 oz. the spring has 27 coils and is 11” long. This was my first build. I don’t think any of this is correct. Am I wrong?

[98Z5V]

15 minutes ago, David Thompson said:

I have a Daytona Tactical AR rifle kit that I built. It is under gassed. On inspection,  I discovered that it has a 7” long buffer tube,  a 2 1/2”buffer that weighs 3.8 oz. the spring has 27 coils and is 11” long. This was my first build. I don’t think any of this is correct. Am I wrong?

The whole recoil system is shiit, to be blunt.   Best bet is the Armalite AR-10 Carbine Recoil System, complete. 

What's your barrel configuration/specs?  

[98Z5V]

Bottom line is this, I'll cut to the chase.

If it's really undergassed with a too-light recoil system, then the gas tube is too short, and the gas port diameter is too small.

How many rounds do you have through this gun so far?

Here's background information on what I'm talking about:

 

[David Thompson]

13 hours ago, 98Z5V said:

The whole recoil system is shiit, to be blunt.   Best bet is the Armalite AR-10 Carbine Recoil System, complete. 

What's your barrel configuration/specs?  

18” barrel. 1-10 twist

[David Thompson]

I’ve shot less than 20 rounds. It doesn’t eject, double feeds. Too many bent cases. Hopefully you have solved my problem   Will measure port diameter later.  What diameter should it be?  Thanks for the input 

[DNP]

That’s most of your issue in that pic. 

[Armed Eye Doc]

1 hour ago, DNP said:

That’s at least some of your issue in that pic. 

FIFY

[DNP]

Sorry. That’s a portion to be later determined as a percentage by dividing this particular problem by (the total number of issues times the magnitude of their relevance). I can put that in a longer equation if necessary. 

[David Thompson]

Thanks. Now I feel more like myself yesterday than I did tomorrow 

[98Z5V]

On 7/5/2021 at 2:27 PM, 98Z5V said:

What's your barrel configuration/specs?  

 

16 hours ago, David Thompson said:

18” barrel. 1-10 twist

That's part of the answers...

16 hours ago, David Thompson said:

 Will measure port diameter later.  What diameter should it be?  Thanks for the input 

 

I don't know yet.  You didn't give me very much on the barrel configuration/specs.  All you gave me was 18" and the twist rate (which doesn't matter).  I need to know what gas system it's using, and since it's a .308 Win caliber, it's either midlength or rifle length - unless it's Rifle +1, Rifle +2 - those come from custom barrel makers,most of the time.

I don't know the diameter of the gas block journal, and that's very important in determining what size the gas port needs to be.  Manufacturer of the barrel?   Throw that in, too. 

That gas tube MUST GO.  You need an Armalite AR-10 gas tube - but I don't know which one to tell you yet, because I don't know what gas system you have.

Edited July 7, 2021 by 98Z5V

[David Thompson]

Have tried to post this twice. Never shows up. Will try again 

20” barrel 

rifle length gas system 

gas port .096”

gas block journal   .752

buffer 2/12” long and 3.8 oz

spring 11” long.  28 coils. Wire diameter .076”

not sure of manufacture.  No markings on barrel other than 308/1:10

[edgecrusher]

Buffer is crap, spring too

[shooterrex]

This will work for a recoil system.

https://www.armalite.com/SACItem.aspx?Item=AR10REKIT01&ReturnURL=/Armalite/Product-Category/AR10-Parts-Accessories/Lower-Receiver-Parts&Category=ac614400-ff09-4cdf-9d35-419a654e7201

[David Thompson]

Thanks once again. I’ve learned a lot. I’ve come to realize that understanding a rifle is just as important as owning one

[98Z5V]

9 hours ago, David Thompson said:

Have tried to post this twice. Never shows up. Will try again 

20” barrel 

rifle length gas system 

gas port .096”

gas block journal   .752

This will work fine for 20" rifle gas, and that journal diameter.  It's a little on the large side by a few thou - but is certainly won't be weak-gassed!