Rare Breed - Slam Fire Triggers - "Forced Reset Trigger"

[RANGER295]

That was possibly with SP1 carriers where the firing pin is unshrouded.
It's only Colt's defeating of the M16 safety design to stop people from making machine guns that would make it possible for a firing pin to get struck with the bolt lugs out of battery.

For the firing pin to actually make it to the primer, the bolt STILL needs to be all the way forward because the spring loaded ejector keeps the cartridge away from the boltface until the case stops against the headspace feature in the chamber and then the bolt carrier pushes the ejector against the case head until there is enough room for the bolt lugs to rotate.
You would have to get the timing JUST wrong enough to get a hammer to fall onto the unshrouded firing pin in an SP1 carrier to hit the magic time where the bolt is not yet locked but IS fully forward so that the firing pin could smack the primer and actually get an igntion before the bolt actually locked up.

With a shrouded firing pin, it's not possible.

Interesting. I need to go look at some of my bolts to see exactly what you are talking about. I had a friend in junior college who made a lightning link in our welding class. We had open shop hours where we could come in and use the shop for basically whatever we wanted. Most kids came in and straight piped their trucks. I practiced for certs. The instructor wanted to know what this little piece of sheet metal that my buddy spent so much time on was for. He told him it was a carburetor part. He used a piece of bandsaw blade to make the upright part. I went out with him on the ranch when he tested it out. I did not want to be anywhere near it because I did not trust it. It functioned flawlessly after a few tweaks and it was broken in. He had a standard AR bolt carrier group in that rife not an SP1 group. I had always thought it had to be an SP1 spec BCG but this one worked fine.

[ar15barrels]

I need to go look at some of my bolts to see exactly what you are talking about.

[SCVlongstroke]

We can’t even wrap our thumbs around a grip so I’m guessing this is a big fat NO.

[RANGER295]

So hypothetically speaking, legality aside, someone could just clip the disconnector and an AR would go full Auto. I am not sure if there would be enough momentum to fire it if the hammer was following the bolt forward but it could be safe to do from an out of battery stand point.

[ar15barrels]

So hypothetically speaking, legality aside, someone could just clip the disconnector and an AR would go full Auto. I am not sure if there would be enough momentum to fire it if the hammer was following the bolt forward but it could be safe to do from an out of battery stand point.

No.
You just get hammer follow.

In order to get full auto function, you need to delay the hammer from falling until AFTER the bolt carrier is far enough closed that the hammer will strike the firing pin and NOT the carrier.
This is exactly what the auto sear does in an m16.

If you remove/defeat the disconnector or spring, the hammer simply rests against the carrier as it's closing.
This will not set off a primer because there's too little energy left in the hammer to set off the primer after the hammer has been resting against the carrier as it closes.