6.5 AR 10 not feeding

[shootertom]

Here are the spec's

Proof 20" cam gas
SLR rifleworks Ti adjustable gas block
JP LMOS carrier
JP SCS - Heavy

Loads are 38.5 gr varget and 130 Sierra Game changers.

The rifle will barely cycle enough to pick up the next round and fails to lock back. So its running on the edge of not picking up the next round. The irony is this gun is a duplicate of one I have already built that runs much better.

Any help or advice would be greatly appreciated.

 

[ZA206]

How many rounds on the rifle/upper/BCG?
What adjustments did you make to the gas block?
Have you shot factory ammo through it, if so, how did it do?

 

[shootertom]

Ive ran about 200 through it so far. I have ran factory 143 eldx as well as my hand loads.

I started the gas block on not pressure and continued to add gas. It always gains some function but never gets enough.

I have also tried a full mass carrier with no luck.

I am leaning towards needing to open up the gas port.

 

[shootertom]

Have spoken with JP and they noted that the Proof barrels come with ports that are usually on the small side.

I am reaching out to proof research tomorrow.

 

[wvfarrier]

I ran into the same issue with a Wilson 20" SS barrel. Gas port was WAY undersized

 

[ColoradoMTBer]

Are you sure you installed the gas block perfectly? I’ve had this and the holes weren’t perfectly aligned. Re aligned them and it solved all my problems.

 

[shootertom]

Are you sure you installed the gas block perfectly? I’ve had this and the holes weren’t perfectly aligned. Re aligned them and it solved all my problems.

Yes sir, I double triple checked with a bore scope.

 

[ColoradoMTBer]

Yes sir, I double triple checked with a bore scope.

Dang. Hope you can get it squared

 

[Jnull]

If you’re running your SCS heavy then lighten it up

 

[shootertom]

If you’re running your SCS heavy then lighten it up

Are you referring to the buffer weights or the spring weight? I did get the spring set form JP and tested all three weights; they all provided the same results.

I have not tried changing the weights themselves.

 

[Jnull]

Either but I’d try lighter weights with the lightest spring, the same amount of gas with less buffer weight should get the results you’re after unless the gas port is just that small. Makes sense in my head at least.

 

[ColoradoMTBer]

Yeah definitely try lighter buffer weights and springs. That would be my next guess

 

[shootertom]

I did speak with Proof Research today and they are eager to help so hopefully they can get me on the right track.

 

[ColoradoMTBer]

I did speak with Proof Research today and they are eager to help so hopefully they can get me on the right track.

Keep us posted. I’m interested to hear the reasoning.

 

[shootertom]

At this point I am looking at the gas port as being too small.

 

[shootertom]

Just a quick update for folks that might be interested.

I measured the gas port and it was within Proof's specs.

On a good note, JP Rifles sent me a new Gas Ring for the bolt that measured .005" larger diameter. This allows less gas to escape around the gas ring. It actually worked amazing. I tested factory and hand loads and they both locked the bolt back and cycled well when feeding the next round from the magazine.

Hopefully this will be helpful to some folks.

 

[bigjake83]

Just a quick update for folks that might be interested.

I measured the gas port and it was within Proof's specs.

On a good note, JP Rifles sent me a new Gas Ring for the bolt that measured .005" larger diameter. This allows less gas to escape around the gas ring. It actually worked amazing. I tested factory and hand loads and they both locked the bolt back and cycled well when feeding the next round from the magazine.

Hopefully this will be helpful to some folks.

I was just going to tell you to swap the JP Has Ring, I've swaped all mine out with Sprinco Gas rings.