Aero Precision OOB

[f2benny]

I built an EPC-9 with their Atlas 16 upper.  I used their bolt, LPK and a Rise 140 trigger.  I have a carbine length buffer tube and used a 6 ounce LUTH 9mm buffer and 308 spring.  My first outing I got the Holosun 512 sighted and the gun was feeding fine and felt good.

 

When I started shooting quickly it blew out the magazine and bent the mag release.  Pics attached.

 

Looking into this in more depth I see this is likely bolt bounce?  I see that my bolt and buffer weigh 14.7 and 6 ounces so they are too light, and the 308 spring made matters worse.  I'm prepared to buy a kynshot and flat rifle spring with an additional 2.5 ounce weight.  With my buffer I don't think I can run two additional weights.

 

Does this seem to be the issue and the right approach to fix?

Edited August 12 by f2benny

[shred]

See how far out of battery it'll drop the hammer.  Bolt bounce can be a thing but isn't necessarily the cause.

[mrvip27]

Good reference material here:

https://blowback9.wordpress.com/

 

Btw...its really important that the 9mm buffer isn't a solid buffer. It needs to be a deadblow similar to how AR buffers are.

 

Also, does your Aero bolt have a ledge or no ledge/lug on the bottom?

 

Is the Rise 240 compatible/made for 9mm?

Edited August 13 by mrvip27

[f2benny]

12 hours ago, mrvip27 said:

Good reference material here:

https://blowback9.wordpress.com/

Thanks

12 hours ago, mrvip27 said:

 

Btw...its really important that the 9mm buffer isn't a solid buffer. It needs to be a deadblow similar to how AR buffers are.

 

I was a deadblow buffer but under weight.

 

Also, does your Aero bolt have a ledge or no ledge/lug on the bottom?

 

No ledge

12 hours ago, mrvip27 said:

 

Is the Rise 240 compatible/made for 9mm?

It's the 140 but supposed to work according to blowback9

 

Edited August 13 by f2benny

[Z-Chaos-Factor]

Shooting quickly and it had an OOB? Yeah sounds like bolt bounce to me.

 

Get a heavier buffer with sliding weight or a hydraulic buffer. 

 

I love the kynshot 5015hd and a single weight. You will loose the ability to lock the bolt back.

 

As for springs get a carbine spring flatwire is better. Just don't get another rifle or 308 spring. 

 

Basically what you said previously is correct. 

 

In addition I'd swap the aero bolt. It doesn't have an important bottom lug that helps prevent OOB. 

 

 

Edited August 13 by Z-Chaos-Factor

[mrvip27]

6 hours ago, Z-Chaos-Factor said:

Shooting quickly and it had an OOB? Yeah sounds like bolt bounce to me.

 

Get a heavier buffer with sliding weight or a hydraulic buffer. 

 

I love the kynshot 5015hd and a single weight. You will loose the ability to lock the bolt back.

 

As for springs get a carbine spring flatwire is better. Just don't get another rifle or 308 spring. 

 

Basically what you said previously is correct. 

 

In addition I'd swap the aero bolt. It doesn't have an important bottom lug that helps prevent OOB. 

 

 

THIS^^