AR brass ejection tuning ?

[texas chase]

Just got a Stag AR Carbine and am really loving it. However, the first few rounds were dented pretty good from the shell deflector. I've heard of people clipping coils off of a spring in order to control this. My question is... which spring is it?

Thanks for any insight.

 

[nbkky71]

To alter the ejection pattern, you'd want to to alter the ejector spring.

That would be part #6

Be advised that to remove the ejector spring, you'll need to compress the ejector and drive out the ejector pin (part #4). This is done with a bolt vise. Here's one made by Sinclair International

 

[texas chase]

Thanks

That's what I thought but I wasn't going to "guess" my way through it. Your help is much appreciated.

 

[rcmodel]

Bolt vice?
A GI gun or my old Colt, you can do it with a bullet tip and maybe an extra hand.

The spring isn't all that hard to compress, and the pin is not that tight.

They were designed to be field stripped with no tools.

Hook a round under the extractor, pivot it into the bolt face, and the case-head will compress the spring.
Use the bullet tip or a punch to push the pin out.

rc

 

[Walkalong]

So how does clipping a coil or two change ejection, and how does it affect it?

 

[rcmodel]

The spring loaded plunger in the bolt face flips the empty or loaded round out the ejection port as soon as the end of the round clears the forward edge of the port.

The more spring, the harder it flips it.

But I believe bolt carrier velocity is what is denting the cases, not the little pebble flipper spring in the ejector.

Clipping the spring may change when it hits the shell deflector slightly, but not how hard it hits it.

That is determined by the bolt carrier / bolt velocity, which is determined by the gas port pressure and recoil buffer spring.

rc

 

[texas chase]

My dad used to shoot NRA high power matches (service rifle division) for years. He told me that some guys would "tune" the ejection spring so that the rifle would spit brass just a foot or two beside them in a somewhat neat pile.

Sounds pretty good to me.