For the big army, it is actually better off for SIG to submit the SIG 516, with some modification.
I have a feeling the "automatic" adjustable gas system envisioned earlier may have something to deal with patent issue, so they have to go with a flat piston head with conventional gas regulator. The self regulating gas system in HK G36 is patented. DE 19615181 A1, US 5824943 A and EP 0802388 A2
There are only so many ways to "self regulate". That is probably the reason why many manufacturers have their hands tied and they end up with a flat piston head, which can't quite self regulate.
Even if it can self regulate, it looks like for the garden variety of suppressors out there there is still not enough operation range for a self regulating system. Otherwise HK won't see the need to put in 2 position gas block in the 416A5
I have a feeling the "automatic" adjustable gas system envisioned earlier may have something to deal with patent issue, so they have to go with a flat piston head with conventional gas regulator. The self regulating gas system in HK G36 is patented. DE 19615181 A1, US 5824943 A and EP 0802388 A2
There are only so many ways to "self regulate". That is probably the reason why many manufacturers have their hands tied and they end up with a flat piston head, which can't quite self regulate.
Even if it can self regulate, it looks like for the garden variety of suppressors out there there is still not enough operation range for a self regulating system. Otherwise HK won't see the need to put in 2 position gas block in the 416A5
Fixed it for you. Darned auto-correct!
As you know, the MCX was not designed for "big Army", but rather at the specific request of US SOF. It was designed for the .300 BO cartridge, which is where the idea of the 9" barrel originated. Later in the design process it was decided to make the MCX multi-calibre to capitalize on existing ammo stocks and to make the system more attractive to potential international buyers. The multi-calibre nature of the MCX is largely responsible for the more complex gas system. The designers originally tried to go with a simple auto-regulating system, but abandoned it just as the first batch of rifles hit the US civilian market. They ended up with the more conventional, current arrangement of user-selected, multiple gas settings.
I suspect that the 9" length of the 5.56mm short barrel is simply a hold-over from the .300 BO barrel of the same length. This particular length works well with the design of the upper receiver (how it mates with the removable section of the handguard) and the gas system, despite the fact that it is a sub-optimal length for 5.56mm performance.


















































