Unobtanium

It will cause more wear and tear than not doing it, but I don't think it will break it. The whole point is...why? That's like asking if kicking the tires on my car as hard as I can will hurt anything. No, not really, but wtf?

But...why?

The design of the M4 is such that dry-firing poses no risk.

Good call if it's true.

Correct on all counts. Benelli CS is awesome.

To the left, IIRC.

Make sure the front-sight is not canted by laying the SG upside down on a granite countertop or something. Buy Kip's Ti mag-tube and spring. Buy a collapsible stock for $600 or so while the market is at a low.

The lowest hardness I have seen for S7 is HRC 45. At that hardness it has a Charpy C-notch (not V, could not find V for it) of over 200J I am curious how hard the OEM piston and OEM BCG are. Would be worth testing.

Have you thought about using S7? I think that it has considerable merit for this application as compared to 15-5. You will note that the Charpy tests for this material at an HRC in the mid 40's are...impressive. Many times that of 15-5 PH at a comparable hardness. Then again, I'm no machinist. I am impressed that you are taking on the piston! Everyone talks a good game, but this is the first prototype I have seen. Otherwise it's usually "in my buddies friend's work garage we are thinking about maybe..."

It would be expensive, but put them in a 4-port barrel and run 3" slugs through it. If they don't snap in a couple hundred rounds, it would be a pretty impressive demonstration. Of course, the bolt-carrier would be screwed most likely.

I agree. You could also take a wood-burner to the OEM forearm and do the same thing and stipple it. Would be kinda cool.

922r compliancy is right after buying a Prius on my feel-good list.

Or I could keep my OEM ones and not worry about it.

Trigger/sear would have been a lot easier and are not subjected to nearly as harsh a life as the piston. I agree that it's nice, but I would have trouble trusting something that requires a very specific hardness and toughness and that has been tested by a couple dozen people and if broken, would prevent the weapon from cycling. Even Benelli had trouble with the operating system initially with their 4-port design, etc. If that can slip through testing at Benelli... I think it's good that this is being made and hate to detract from it, but I personally would not buy it until a LOT of testing has been done. Just my .02

I can eye-ball the picture and tell you that they aren't the same. Not that it is critical that they be the same, but I figure they were designed with certain angles, etc. for a reason. It begs the question from others: "what else is different?" Being as this is a highly stressed part, material and heat-treat are going to be HUGE. THen you will need to test the design pretty hard to ensure that it is durible. Just a lot of reliability headaches/worries with this part.

Why did you deviate from the original dimensions of the piston?

Yes, buy one.

Errr...I thought you owned one? Yes. It does.

I have a great time going shooting with my M4. Do you actually just set yours in the corner and not shoot it?

Eh, total fail on my part, 12ga.

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Vinci is more delicate. I would take the M4.

Stock is in very good condition, shows slight finish-wear around sling hole and inside stock-tube from light/normal usage. $610 Shipped W/in CONUS via USPS Priority Mail with Delivery Confirmation. Payment via USPS Money Order only. USPS MO to be shipped Priority mail w/Delivery Confirmation PM on this site. Price is non-negotiable.

Then do that.

Can you install it with no wiggle and still get the trigger-group in?