M-16 BCG vs AR-15 BCG ejection/extraction

[TheBelly]

Does my 6.8 SPC upper need an M-16 (full) bolt carrier if the brass is getting ejected easily? It currently has an AR-15 bolt carrier. 'Easily' is defined as: no marks on the brass deflector and the brass is landing about 15 feet away between the 3 and 4 o'clock.

My thought is that if the bolt was moving too fast, then the brass would be hitting the brass deflector before the ejector/extractor combo has a full chance to do their job. The other side of the coin, I think, is that the extractor and ejector seem to be doing their jobs pretty well, seeing as the brass is flying fairly easily.

How much does the bolt carrier itself have to do with the extraction and ejection distance/direction?

[Sgt_Gold]

Ejection patterns are more dependent on the ejector spring than anything else. Are there any issues with damage to the cartridge rims that might indicate over gassing or other issues? If not, leave well enough alone because there is nothing to fix.

[MarkG]

Does my 6.8 SPC upper need an M-16 (full) bolt carrier if the brass is getting ejected easily? It currently has an AR-15 bolt carrier. 'Easily' is defined as: no marks on the brass deflector and the brass is landing about 15 feet away between the 3 and 4 o'clock.

My thought is that if the bolt was moving too fast, then the brass would be hitting the brass deflector before the ejector/extractor combo has a full chance to do their job. The other side of the coin, I think, is that the extractor and ejector seem to be doing their jobs pretty well, seeing as the brass is flying fairly easily.

How much does the bolt carrier itself have to do with the extraction and ejection distance/direction?

Imagine that, a spent cartridge case hitting the brass deflector? Ejection patterns change with the ammo you are using. The weight/style of your bolt group will have no measurable effect on your ejection pattern.

[TheBelly]

Imagine that, a spent cartridge case hitting the brass deflector? Ejection patterns change with the ammo you are using. The weight/style of your bolt group will have no measurable effect on your ejection pattern.

Well, if the brass doesn't normally hit the deflector, and then it starts to, isn't that an indicator that there's something going on? I'm pretty mindful of changes in the way the gun operates throughout the firing cycle. I'd like to know what 'normal' is, per say, just so I have a baseline for when things go a little wonky.

forgive my ignorance/lack of knowledge of the technical details, but can't an overgassed gun mixed with a buffer that's too light cause problems, such as the rim getting ripped off the spent case?

Currently there aren't any scoring marks, deformed case rims, issues, so I'll just continue to shoot until some significant change happens.

[MarkG]

Well, if the brass doesn't normally hit the deflector, and then it starts to, isn't that an indicator that there's something going on? I'm pretty mindful of changes in the way the gun operates throughout the firing cycle. I'd like to know what 'normal' is, per say, just so I have a baseline for when things go a little wonky.

forgive my ignorance/lack of knowledge of the technical details, but can't an overgassed gun mixed with a buffer that's too light cause problems, such as the rim getting ripped off the spent case?

Currently there aren't any scoring marks, deformed case rims, issues, so I'll just continue to shoot until some significant change happens.

Does normal mean it is correct? Brass deflecting forward is not a sign your weapon is over gassed. There are multiple variables involved and it is improbable that you will be able to identify them let alone maximize them all. Chasing an ejection patterns will inevitably run you face first into the law of unintended consequences. The AR-15 platform is not a box of Lego building blocks. This forum and others are littered with hundreds of thousands of threads from people who believe it is. Snap, snap, click, click check out my new build and then its off to Brownell's or some other parts company to spend more money buying parts to chase gremlins. Reduced power springs, extra power springs, plumbing parts for your extractor. It never ends and all the while the parts companies are laughing their ass off all the way to bank. Remember, the worst problems can always be found in the battery storage compartment on your stock.

[JSantoro]

Well, if the brass doesn't normally hit the deflector, and then it starts to, isn't that an indicator that there's something going on?

Lemme get this straight: you're looking to "fix" a gun that, by all indications, is doing what it's supposed to be doing?

The brass deflector is there for a reason...to deflect brass (despite the totally misleading nomenclature derp derp) so as to ensure it can be shot left-handed and not have the shooter getting pelted. Why in the world would you think that the deflector is supposed to be unmarked?

Sounds to me like something about your rifle may have worked itself in, and you're now chasing the mice running around in your head. That's forgetting for the moment what Pilot already said about different ammos and whatnot.

When you say "if the brass doesn't normally hit the deflector" is a strong indication that, instead of somethig being wrong with the gun, that there's something very much off about how you define the way the gun is supposed to function, and that a trip back to the stickies might be in order.

[heartbreakridge01]

Lemme get this straight: you're looking to "fix" a gun that, by all indications, is doing what it's supposed to be doing?

The brass deflector is there for a reason...to deflect brass (despite the totally misleading nomenclature derp derp) so as to ensure it can be shot left-handed and not have the shooter getting pelted. Why in the world would you think that the deflector is supposed to be unmarked?

Sounds to me like something about your rifle may have worked itself in, and you're now chasing the mice running around in your head. That's forgetting for the moment what Pilot already said about different ammos and whatnot.

When you say "if the brass doesn't normally hit the deflector" is a strong indication that, instead of somethig being wrong with the gun, that there's something very much off about how you define the way the gun is supposed to function, and that a trip back to the stickies might be in order.

I would agree! My brass deflector always has marks on it!

[Terlingueno]

I thought the brass deflector was integrated into the receiver to...wait... deflect brass

[TheBelly]

Thanks to everyone reeducating me on the fact that a brass deflector is there to deflect brass. (sarcasm)

I am probably not articulating my question properly, so I'l just let this thread fade into page 60 and report back when something changes/breaks/etc.

Thanks for all the help, and humor, and whatever else the rest of you were trying to go for (derp).