[ SIG Model U ]
Hi guys, thanks for tuning in to another video on ForgottenWeapons.com.
I'm Ian McCollum, and I am here today at the Rock Island
Auction Company taking a look at some of the guns
that they're going to be selling in their upcoming
April of 2018 Premier Firearms Auction.
And one of them is this very unusual and
very interesting prototype SIG Swiss self-loading rifle.
This is a Model U, and it is one in a whole series
of semi-automatic prototypes that the Swiss, well SIG, was experimenting with
from the 1920s all the way through the 1940s.
Ultimately Switzerland would adopt the Sturmgewehr 57,
which is a roller-delay blowback action rather similar to the HK G3.
But they had several decades of experimentation before they got to that point.
Now the Model U fits kind of in the middle of this series.
These started in the early 1920s, the Model U was manufactured in 1942 and '43.
And they made a total of, I believe, 16 of these.
The serial numbers are in the 70s, and 80s.
And this is because SIG ... numbered all of their prototype rifles in a single continuous series.
So the next major rifle after this one was the SK-46,
those have serial numbers in, I believe, the 90s and low 100s. That's just how they did it.
Now over time as SIG made these different designs,
they got a little more streamlined and a little more practical every time,
but they're all pretty darn Swiss.
So what we have that stands out on this one
is ... basically a gas-tappet system with a full length operating rod.
So the gas port is up here, but the gas piston is very similar to that of the M1 carbine.
It has a tilting bolt that locks up into the roof of the receiver.
And then just typical Swiss complexity and machining perfection to everything.
The one other really interesting feature of these is
that they do all have telescopic sights on the left side of the receiver.
These are permanently attached, and they are the exact same style of sight that was on the K31/42,
which was the sniper/marksman's version of the bolt-action K31.
This is a whopping 1.8x power scope. It's a little tiny thing.
It does have range adjustment out to 1,000 metres.
And it's got this cool ... periscopic sort of objective lens on it, which I'll show you in detail.
Here on the rear receiver cover of the rifle we have the primary markings.
This is SIG. "Industry", the official spelling at this time, and for a while before,
was actually with a "J", that's not misspelled, that's how it's intended to be.
And that's SIG, or SJG.
Neuhausen is the location in Switzerland, Model U, and this is number 75.
Now this range adjustment leaf is actually for adjusting the scope's point of aim.
They have this connected to a little cam built into the scope.
So as I push this forward you can see that this cam pivots,
and that's going to change the position of the reticle inside.
So as you raise that up it adjusts for range out to, ... allegedly, 1,000 metres.
Good luck shooting at 1,000 metres with 1.8x magnification though.
We also have a second leaf up here on the front of the rifle, which is the actual iron sight.
And it works the exact same way, except it's not built into a scope.
Now should you be using the actual iron sights or transporting the rifle,
you can take this and snap that down into
the side of the stock there to kind of keep it out of the way, that's a little cool.
And just in general this is a very low profile, very small optic.
So it doesn't really add much to the weight or bulk of the rifle to have it on there.
I'm sure the Swiss were experimenting with the idea of
making an optical sight standard on all of their rifles.
Although they would choose not to do so when they eventually adopted the Sturmgewehr 57.
A couple of controls to look at here. We have a safety lever on the side.
Obviously forward, "F", fire.
"S" and "F" conveniently stand for safe and fire in English,
and "sicher" and "feuer" (safe, and fire) in German as well.
In fact beyond that, they'd also stand for safe and fire in French, so very convenient for the Swiss.
We have a pretty standard bolt handle.
This does lock open on an empty magazine.
You'll notice that there is this large cutout at the top.
That, although I haven't tested it, I'm quite certain is sized
to use K31 pattern or G11 pattern 6 round charger clips.
In order to close the bolt, we have a bolt release back here
which allows that to close.
Now you'll notice, if I don't give it much ... space to start,
the bolt doesn't entirely go into battery.
And keep that in mind, because you'll see why when we take it apart.
There it is fully in battery, you can see the bolt lifts a little bit higher.
Lastly for controls, we have a magazine release here.
Like the K31s, G11s, K11s, etc. these magazines have a latch on the magazine themselves.
This one is helpfully marked with all sorts of information.
It's a SIG Neuhausen, a Model U, it's in calibre 7.5 which would be 7.5x55 Swiss.
This is the magazine for gun number 73, slightly mismatched.
And that 12, I am quite sure, indicates a 12 round capacity
which would be two full standard charger clips.
We have a little bit of a ventilated handguard up here at the front.
Handguard and stock go basically all the way to the front of the gun.
Bayonet lug, very Swiss pattern hooded sight.
A nice square, precise, easily adjustable front sight, as you would expect.
And a sort of semi-pistol grip, very much like the Schmidt-Rubin rifles and carbines.
Now, let's take this thing apart.
Begin by removing the magazine.
Next I want to remove the bolt, so I am first going to lock it open like that.
Then ... we're going to take this lever and pop it over into this position,
and put the gun into safe.
Then ... this top cover pivots up, and comes off of the gun.
Just that piece alone I think has more machine time in it than a late-war Kar98k.
Now the bolt is handily back here where we can access it.
And I can just ... lift ... the bolt ... right out of the action.
Now the locking surface for this is the very front edge of the receiver wall, right there.
It's hard to get a good angle on it, but this flat surface right at the front.
Now, in its locked and ready to fire position the bolt looks like this.
And this surface right here is what's locking up against the top of the receiver.
The firing pin is down here, and this would be equivalent to having just fired.
So you can see that the firing pin is protruding through the ... front of the bolt face. ...
This is the striker itself right here.
This little surface right down there is what hooks onto the sear.
And you can see the sear right there.
So when I pull the trigger, that sear drops down and releases the ... striker.
And then when the bolt is actually cycling, this snaps back up together.
That forces the striker tail up where it's going to hit the back end of the bolt face.
That prevents the firing pin from coming out the front of the bolt, so it can't fire.
... This wedge is what actually pushes this all down and out of connection, like that.
So when this goes to lock up, it has to actually push this apart like that.
Now you remember just a minute ago when I was dry cycling this thing,
you had to give the bolt a fair amount of space to get going
in order for it to lock up completely. That is because of this block.
So if it didn't have enough speed, it didn't have enough force to snap this down,
and split this piece away from the bottom of the bolt.
I don't know if it comes across on camera, but it takes a fair amount of energy to do that.
Not a whole lot else on the bolt to point out, we have a big long extractor spring right there.
This is going to eject out the top, that little cutout is for a fixed ejector.
Actually I should point out, we do also have this lug on the side of the bolt.
That lug sits in this recess right here.
And you can see there's a little cam on the bottom.
... This is the operating rod by the way, connected to the bolt handle.
When this goes all the way forward, it's going to force the bolt up
against this surface, and into battery.
Now in order to show you the operating rod and the gas system,
I'm going to have to take the action out of the stock.
So I'm going to take off the two barrel bands.
And these two screws that connect the trigger guard up into the action.
These guys, by the way, have locking screws.
So what I have to do first is rotate this into alignment with that screw.
There we go, and then ...
I can unscrew this.
Alright, we've got the action screws done. Now the front barrel band has a screw and a hinge,
so we'll just take it off completely.
There we go.
And then the rear barrel band doesn't have a hinge,
so we'll just loosen it and then we can slide it past that.
There we go.
Now the handguard just lifts right off.
And then I can take the stock off of the action.
Alright, now we can see what's going on underneath.
We of course have a mainspring right here, that's on a guide rod connected to this block.
Then we have a very long operating rod which is going to connect here,
it hits the bolt handle.
And then the operating rod comes all the way forward out to the muzzle here.
So, that goes backward.
And in fact you can see that when I push this back,
you see that this guide rod is connected all the way back there.
And then what's actually motivating that is this little gas piston right here.
That comes out like that, gives a smack to the operating rod and stops.
So that only goes that far.
Very similar to an M1 carbine.
So there is a gas plug here that I can unscrew.
In fact it's kind of weird. This is just like a locking screw.
So once this is back, then you can unscrew this,
which is just a plug in the front of this cylinder.
And then ... having this plug in place prevents this from rotating.
Which is what I believe is setting the gas block in place.
So, set the gas block. This goes in to set the right spacing for it.
Then you screw in the gas plug,
which ... fits in one of these little concave gaps in this nut.
And then you screw this down on top to make sure that this can't back out.
So there's like three interlocking reinforcing bits here to make sure that nothing moves.
Anyway, for all the expense and the machine time that went into this,
it's not actually that complicated of a system.
It's a gas tappet and a very long and extravagantly manufactured operating rod.
And the trigger mechanism is kind of the same way.
So we've got a whole bunch of stuff moving with the trigger here,
but ultimately what it's doing is just pulling down a lever here,
which ... pulls down the sear.
You can't see it now because I'm in the safe position (safe - fire).
But what this does is ultimately just drop that sear
to allow the firing pin, the striker to go forward.
There's a disconnector right here.
That's going to push up, you can see it moving these, that resets the trigger.
So that ... when you fire one shot the trigger resets, and it doesn't fire fully automatic.
There's not a whole lot more to this really.
A lot of machine time went into it, if you gave this project ...
what I want to say if you gave this project to the Germans in 1944
they would figure out a far simpler way to have done it.
But then again, some of the German Volkssturm rifles have
ludicrously complicated trigger mechanisms like this anyway.
So - give it to the Americans, we'd have figured out a simple way to do that.
So pretty cool to get to see another one of the building blocks of the SIG
semi-automatic rifle experiments, and prototypes, and the whole developmental series.
If you're interested in the other guns that were in this series,
definitely check out the playlist that I have linked at the end of this video,
which ... covers a whole bunch of them, all the ones I've been able to do video on.
And if you would like to add this rifle to your own collection,
or start your own collection of SIG prototypes,
well, take a look at the description text below the video.
You'll find a link there to Rock Island's catalogue page on this rifle.
And that has their pictures, their description, their value estimates,
and everything else you would need to know to place a bid on it
either through their website, or live here at the auction in April.
Thanks for watching.