Failure to extract in a 9mm carbine

[Nemesis Lead]

Hi guys,

 

I just got a TACCOM LW Upper.  The thing is amazingly accurate and lightweight, but I am getting a fair number of failures to extract (brass gets stuck inside the gun and gets crushed).  About 10% of rounds get hung up like this.

 

My ammo is 147 grain 135 PF loads that work perfectly in pistols and my JP GMR-13 carbine.  I am guessing that the issue is with the buffer and buffer spring.  I am running a Springco AR-15 extra power (red) carbine spring and a Blitzkrieg 9mm hydraulic buffer.

 

The gun ejects brass about 6 feet.  I tend to run carbines with a moderate amount of lubrication.

 

The lower is a JP GMR-15 lower.

 

Any thoughts would be appreciated.  

 

 

 

 

Edited February 24, 2018 by Nemesis Lead

[BartCarter]

Check your ejector. It should be as close to your bolt as possible. The closer, the better. You can adjust it with small, light hammer taps or pliers. 

[MikieM]

Try a standard AR carbine spring. It may solve your problem. That Sprinco "red" is pretty stiff with a load as light as yours, and the buffer only weighs about 5 ounces, or so.

[L9X25]

3 hours ago, BartCarter said:

Check your ejector. It should be as close to your bolt as possible. The closer, the better. You can adjust it with small, light hammer taps or pliers. 

 

You can get some adjustment by loosening the set screws, moving it, then re-tightening the set screws.  They have it machined so that some adjustment is possible without bending.

[Nemesis Lead]

Thanks guys.  I checked the ejector.  It is already pretty darn close to the bolt and similar to all of my rifles that DO work.  I also ordered a lighter buffer spring.  Any other thoughts?

[MikieM]

I think you're good to go for the time being and I'll wager you'll find your gun shooting a bit softer, as well. 

Let us know how things turn out.

[bladewurk]

Chamber brush + polish??