Sig MCX Spear vs. MCX Spear LT

[PNorris]

I have been trying to find information on the web, as it appears that the Operating systems are very different. The MCX Spear appears to use an AK style long stroke piston design, whereas the LT appears to use an AR 18 type system. Only the LT appears on Sig's website. I prefer the AK style system and I was curious if this going to offered to the public. If so, I wonder if only with their new hyped up cartridge and not the 5.56.

MCX Spear: https://www.youtube.com/watch?v=hO4IKxECNzI&t=489s At about 7:48 in this video

Spear LT:https://www.youtube.com/watch?v=DYZzi7gPQ9M&t=163s At about 2:20 in this video

Thoughts or anyone with knowledge?

[constructor]

I have been trying to find information on the web, as it appears that the Operating systems are very different. The MCX Spear appears to use an AK style long stroke piston design, whereas the LT appears to use an AR 18 type system. Only the LT appears on Sig's website. I prefer the AK style system and I was curious if this going to offered to the public. If so, I wonder if only with their new hyped up cartridge and not the 5.56.

MCX Spear: https://www.youtube.com/watch?v=hO4IKxECNzI&t=489s At about 7:48 in this video

Spear LT:https://www.youtube.com/watch?v=DYZzi7gPQ9M&t=163s At about 2:20 in this video

Thoughts or anyone with knowledge?

They are both short stroke piston systems. https://www.militaryfactory.com/smal...llarms_id=1286

The IWI x95 Tavor has a long stroke system.
ETA- IWI Galil and PWS has a long stroke system.

[PNorris]

If you look at my videos the operating systems are completely different. Whether it is short stroke or long stroke the OS are totally different. I wonder why Sig did not change the LT to use this new OS.

[constructor]

If you look at my videos the operating systems are completely different. Whether it is short stroke or long stroke the OS are totally different. I wonder why Sig did not change the LT to use this new OS.

If you are just looking at the spring then yes the springs are different but that does not define the operating system.

Long stroke system means the piston travels the same length that the carrier/bolt does.
Short stroke means the piston travels less distance than the carrier/bolt does.
The AK has a long stroke system, the Sigs have a short stroke system.

[PNorris]

Watch the videos. Does not look like they share a single part. If you want to speak in general terms then yes they are both piston systems, however, you are ignoring the general question as to why sig did not update the entire line with the new OS of the Spear.

[constructor]

Watch the videos. Does not look like they share a single part. If you want to speak in general terms then yes they are both piston systems, however, you are ignoring the general question as to why sig did not update the entire line with the new OS of the Spear.

What does operating system mean to you?

[PNorris]

Now you are just being an a-hole. I am done feeding you.

[constructor]

Now you are just being an a-hole. I am done feeding you.

I'm sorry you don't understand. The Spear was designed first and the Spear LT second so who's to say which is updated. I say a single spring or 2 is nothing but a design element. They may have thought 2 small springs would not control the movement of the 308 sized BCG or maybe a single spring in the Lt may have been too large in diameter and the receiver on the Lt would have been as large as the 308 version. You would need to ask their design team directly to get that answer.

[PNorris]

And you are . . . . . wrong. MCX dates back to 2015. Try again smartass the Spear LT is merely an MCX with some elements of the spear.

[Defaultmp3]

Only the LT appears on Sig's website. I prefer the AK style system and I was curious if this going to offered to the public. If so, I wonder if only with their new hyped up cartridge and not the 5.56.

The SPEAR has been commercially available for over a year now: https://www.sigsauer.com/spear.html. They sold a limited edition kit in .277 Fury as a factory SBR and with a can during a first run: https://www.sigsauer.com/blog/now-sh...cx-spear-rifle

As a large frame system, why would they ever offer it in 5.56×45mm? There's the hope that it'll be available for 7.62×51mm and 6.5 CM, but small frame calibers seem like it'd be extremely niche and probably institutional only (like the retrofit kits for the SCAR 17).