AR 9mm
- Thread starter 1LtBlack
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That is normal part of ejection. Your sizing die will iron that right out.
- Nov 3, 2010
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load away, but the flattening is coming from more than likely too much extraction. Not sure how your PCC is "driven" i.e. blowback, gas, etc, but Id imagine that your cases are being extracted next to/behind you, as its "overgassed". Have you tried a heavier buffer, stronger spring so the extraction comes out more 90 degrees to the ejection port? If you "tune" the extraction, it will stop slamming the cases so hard, and stop flattening them like that.
Similiar way you tune a gas driven AR extraction. Either adjust the gas, or use a stronger spring/heavier piston, and "tune" the extraction so that the cases come out 90-100 degrees from your POA.
Hope this helps.
Similiar way you tune a gas driven AR extraction. Either adjust the gas, or use a stronger spring/heavier piston, and "tune" the extraction so that the cases come out 90-100 degrees from your POA.
Hope this helps.
there is no case deflector on a proper 9mm AR, it is a hot gas deflector and your cases should not be hitting it.
9mm ARs are really tricky to tune. If you care about it, there are several threads on ARFCOM about hydraulic buffers, tungsten weighted heavier buffers (9+ ounces), ramped bolts, stroke length, buffer tube blocks, and all sorts of things; some don't matter much unless you're running full auto, some do
Unless this is a high volume rig, and it runs fine, I'd leave it alone and resize that brass and move on to more pressing matters
9mm ARs are really tricky to tune. If you care about it, there are several threads on ARFCOM about hydraulic buffers, tungsten weighted heavier buffers (9+ ounces), ramped bolts, stroke length, buffer tube blocks, and all sorts of things; some don't matter much unless you're running full auto, some do
Unless this is a high volume rig, and it runs fine, I'd leave it alone and resize that brass and move on to more pressing matters
Thank you everyone! I will continue with the reloading. Have ordered a 8.4 Oz buffer. Mine was at 5.5 oz. Will see if this helps. This is my first PCC so still new to me.
If you're running a db system, try out a hydro buffer, been running a blitzkrieg 9mm with a tubb flatwire sping for years. I have so many various spare buffer spring weights, 9mm heavy buffers, spacers etc sitting around now.
Dramatically reduces the felt recoil to and fro and overall wear on everything else.
Dramatically reduces the felt recoil to and fro and overall wear on everything else.
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So a proper 9mm ar has no shell deflector? You sure about that?
Better go take a look at the OG Colt SMGs in 9mm. That big piece behind the ejection port is a shell deflector. Even the MP5 has a shell deflector on it, a small piece of sheet metal that does the job
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I’ve only seen a handful that didn’t. Most just aren’t as obvious as they used to be due to smaller ejection ports. Most manufacturers have started to blend them into the machining of the upper better for aesthetics. If you’ve ever shot a 9mm upper with a full length ejection port and no deflector, you quickly realize that you end up with empty cases flipped around the bolt as they are thrown off. At least that was my experience when I tried to build around a side charging upper over 10 years ago. My current one is the end result of that failed test and was SBRd on 2013/14 ish. It runs like a champ.
I Haven’t. All the 9mm ars I’ve shot have been pcc and they have no deflector.
I’m sure if you converted a 15 to 9mm they would, but most dedicated ar9 do not that I’ve observed.
I’m sure if you converted a 15 to 9mm they would, but most dedicated ar9 do not that I’ve observed.
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Just a few from a 5 minute search. All dedicated uppers/builds from manufacturers like Aero, CMMG, Foxtrot Mike, PSA. All have shell deflectors either attached or machined in the upper.
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Just a few more. Only place I have seen that don’t have an obvious shell deflector is Quarter Circle 10, and Angstadt Arms
Do your homework. It I is NOT a case deflector. Read Black Rifle 2. Hank Tatro design. GAS deflector
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It’s actually dual listed. Many well known gun folks even just call it a deflector. Larry Vickers called it a shell deflector as well when he did a video on the 9mm SMG lineup. Depending on what text you read, it is referred to both at some point and time.
As for being a gas deflector, I could lean towards that on the old colt gun. Clearly the new modern setups would not block ANY gas. If it was primarily there for one reason and one reason only, it then I wouldn’t even have replied here. Seeings how manufacturers have moved away from the large version seems even they know what it’s used for.
I would like to see in writing where a credible source acknowledges it is a shell deflector. Colt (Hank Tatro) designed these rifles. It required numerous work a rounds from the 556 design. They tested it extensively in the 1980s. That some copycat 40 years later mistakenly thinks it’s a shell deflector, designs his upper with a perfunctory version it it, and calls it a shell deflector would not surprise me but that doesn’t make it so.
From the most widely recognized expert on the matter: https://smallarmsreview.com/the-colt-9mm-nato-smg-carbine/
From the most widely recognized expert on the matter: https://smallarmsreview.com/the-colt-9mm-nato-smg-carbine/
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Oh look, another thread where the OP's question is answered early on but then devolves into a stupid semantics argument about something that doesn't matter. New day, same SH..
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That article was written in 2022. And if you are saying Larry Vickers is some copycat, maybe you should go read up some.
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