Long stroke SureFire Carrier

[Leaveammoforme]

I like the idea but, the first thing that jumped out at me is the one gas key screw.

I'm sure one screw that is of proper material and is installed correctly will be more than enough to secure the key. I also understand that the key will need shortened to gain the desired longer stroke.

All that but I'm still like "One screw key?!"

[cynical]

I'm not sure it's a single screw. From the pics it looks like the rear of the key (and the screw) is recessed into the carrier, not cut off completely.

[BufordTJustice]

I'm not sure it's a single screw. From the pics it looks like the rear of the key (and the screw) is recessed into the carrier, not cut off completely.

That's what I'm seeing. Either that or it's in a keyed-slot and installed from the rear (much like a front-to-rear sight dovetail).

[Leaveammoforme]

I'm not sure it's a single screw. From the pics it looks like the rear of the key (and the screw) is recessed into the carrier, not cut off completely.

That's what I'm seeing. Either that or it's in a keyed-slot and installed from the rear (much like a front-to-rear sight dovetail).

This sounds more right than what I thought I was looking at.

[the_1iviper]

spring loaded counterweight in the end of the carrier , interesting.

i wonder what they've done with the porting in the carrier

[tom12.7]

This is Sullivan's work. It is interesting to see how the commercial product turns out. None of this is new really at all in concept, I would've hoped that more of this could have been marketed 20 years ago.
It would be interesting to see how this commercial version compares when looking deeper into things. Extractor pin retention can vary, depending on the extended length of the double cut cam compensation. Extending a portion of the bore for retention can help a lot, but that extended portion must be compatible with the BE, others that do it are not always so. Another interesting thing to see would be the free space in the action buffer, there's possibilities here. The reduced wire gauge spring with more active coils can be a big help here for the action spring, but would really need a production part to test it. With modern machining there are other gas key options that may be better or worse, a partial integral key "may" end up a better solution, depends on the execution of it. Spring loaded weights in the carrier showed up in 5.56 ARs not long after the 9mm AR came about, with different successes, this looks pretty good though.
This offering may be great, just depends on how they offer it. I would still prefer to back spot face the gas tube hole in the upper for key clearance for added length and use a custom or dedicated charging handle when using the standard M16 FOW upper to extend the cam path and extended bore for retained extractor pin applications.

[P2000]

This is Sullivan's work. It is interesting to see how the commercial product turns out. None of this is new really at all in concept, I would've hoped that more of this could have been marketed 20 years ago.
It would be interesting to see how this commercial version compares when looking deeper into things. Extractor pin retention can vary, depending on the extended length of the double cut cam compensation. Extending a portion of the bore for retention can help a lot, but that extended portion must be compatible with the BE, others that do it are not always so. Another interesting thing to see would be the free space in the action buffer, there's possibilities here. The reduced wire gauge spring with more active coils can be a big help here for the action spring, but would really need a production part to test it. With modern machining there are other gas key options that may be better or worse, a partial integral key "may" end up a better solution, depends on the execution of it. Spring loaded weights in the carrier showed up in 5.56 ARs not long after the 9mm AR came about, with different successes, this looks pretty good though.
This offering may be great, just depends on how they offer it. I would still prefer to back spot face the gas tube hole in the upper for key clearance for added length and use a custom or dedicated charging handle when using the standard M16 FOW upper to extend the cam path and extended bore for retained extractor pin applications.

So is the cam pin path extended or different than a regular BCG? From reading the vague descriptions floating around the web I didn't see that.