Pull-out rather than push-through does make more sense for plastic link. I’ve seen plastic M13 link but apparently it’s not as robust as the metal. Not really a surprise.

If your M14 flashbacks werent already in effect, I present: SIG working to develop a stamped steel magazine for the NGSW.

https://soldiersystems.net/2022/07/25/sig-sauer-develops-in-house-magazine-production-capability/

In the comments, Eric of SSD mentions that the 6.8 projectiles are being harsh on the Lancer mags, which may be a reason for this. Although how they would be worse than M855A1, or how relatively soft steel would be much better against Hardened steel / Tunsgten, is an open question.

A loaded M14 mag was 1.5-1.62lbs depending on source...

gatnerd said:

In the comments, Eric of SSD mentions that the 6.8 projectiles are being harsh on the Lancer mags, which may be a reason for this. Although how they would be worse than M855A1, or how relatively soft steel would be much better against Hardened steel / Tunsgten, is an open question.

Other possible reasons for SIG developing in-house magazine production:

- Eliminate reliance on Lancer.

- Increase SIG profits.

Oh, those are absolute factors to bring manufacturing in-house, and are totally legit.

But, whats very odd here is the choice of steel for the in-house 6.8 mags.

-Polymer mags are much easier to mass manufacture and are cheaper to produce compared to steel mags (so higher profit margin for SIG)

-Polymer is much lighter and is what most modern rifle mags are made of

-Magpul Gen 3 mags have already shown a 100% polymer mag works well with EPR when designed for it

Maybe things doesn't scale up / down so easily.

Maybe a polymer mag that is OK with a 12 g cartridge and an impulse of 6 N.s, will struggle to maintain the same level of performance with a round nearly twice as heavy and the increased impulse & recoil velocity?

The M80A1 is mainly used in guns that don't have polymer mags.

EmericD said:

The M80A1 is mainly used in guns that don't have polymer mags

The Armys new squad DMR CSASS uses a polymer mag; I havent heard that it will use special match ammo so I assume it would use M80A1?

gatnerd said:

The Armys new squad DMR CSASS uses a polymer mag; I havent heard that it will use special match ammo so I assume it would use M80A1?

Or maybe M118LR?

gatnerd said:

The Armys new squad DMR CSASS uses a polymer mag; I havent heard that it will use special match ammo so I assume it would use M80A1?

Looks like they use M118LR.  Note 0:10-0:20 in https://youtu.be/meIJgWZ-CTM?t=10

Also:  "SIG Sauer initially developed a ballistic drop compensating (BDC) reticle for the M80A1 round at the Army's request...  Later, the Army requested (and now issues) a BDC reticle developed for M118LR..."  SIG Sauer Tango6T 1-6x24mm Review - Guns and Ammo