Hi guys, thanks for tuning in to another video on forgottenweapons.com
I'm Ian, and today I'm taking a look at a really interesting prototype Spanish
rifle from right after World War Two. This is a CB-51, which interestingly is a
designation that tells you very little just by itself, because there are at
least two other CB-51 rifles that I'm aware of that are totally different from this one,
mechanically. What that designation does tell you is that this was designed or
made in 1951, and the CB stands for "Calzada-Bayo". The designer--or at least
the guy whose name got associated with these guns--is a Spanish artillery
officer by the name of Joaquín De La Calzada-Bayo, and he was
originally posted to the La Coruña Arsenal in 1943, where he presumably worked
through World War Two and then he stayed on afterwards as an arm's designer. I
really don't know much about the guy himself, but I have--we have--this rifle in
front of us here, and I've gotten pictures of several other guns that were on
display at the La Coruña Museum that are also CB-51's, and a few other
designations that are clearly experimental guns, but different ones. So
what this gun is, it's obviously--and you'll see this when we look at it up
close--heavily influenced by the M1 Garand. It has an op rod, gas system,
and despite the Mauser-looking front end, it's got a gas port up here and an
op rod coming down the side of the barrel, a two-lug rotating bolt, very much
like the M1. However, it does have a stripper clip guide up here and it has
these rather unusual size magazines. I can't confirm it because it's not--it's
not marked on the gun anywhere but I believe this is actually chambered for
the 8x33, or 8 millimeter Kurtz cartridge, that was originally used in
the German Sturmgewehr rifles. The Spanish, [and] several of the the design
engineers from the Mauser company ended up working in Spain right after World
War Two as arms designers. The Spanish were interested, as were a lot of other people,
in the the new sort of intermediate "assault rifle" cartridge, and they
developed a number of guns in 8mm Kurz. In fact, one of the other CB-51 rifles
on display at La Coruña used basically what looked like modified
original StG magazines.
These are shorter, I suspect these are somewhere between 15 and 20 round
capacity, and then this rifle also has a short magazine that only holds I believe
five rounds,
that's actually a flush fitting mag in this gun. So there are a number of interesting
mechanical elements to this that we'll take a look, at but just as a general
overview this is one of the many guns that the Spanish military was tinkering
with after World War Two. Everyone was kind of looking at new guns, a lot of
countries--most countries--didn't yet have a standard-issue semi-auto, and
so a lot of them were looking at the developments that had arisen during the
war. Especially, you're talking about the major combatant nations; Russia, Germany,
the United States, fielding pretty much all new semi-auto rifles and then these
smaller military forces, countries like Spain, are are looking to take advantage
of all the RND that the big countries did, and spin off their own--what they see
is the best versions of these new semi-autos to adopt. Now ultimately this
platform didn't go anywhere,
what the Spanish ended up adopting (and developing) was the CETME rifle, which
went through a number of iterations. If you take a look at the blog post I have
on some of the other CB-51 designated rifles, you can see a development towards
the CETME rifle, in some areas there. Anyway, why don't we go ahead and take a
closer look at this one? I'll show you how it operates and a couple of the neat
features like this thing.
Alright, so we've got this all disassembled, pulled it out of the stock
so there's actually really not much going on in the stock...we'll set that
aside
Handguard, same kind of thing, clearly handmade. In total, 12 of these guns were
manufactured by La Colonia. They were all unfortunately deactivated according to
Spanish legal requirement, so two holes [were] drilled into the barrel. There is
actually one other example of this gun in the United States. It's in the same
condition, unfortunately. This was required in order to be able to sell the
guns in Spain which was done when they were taken out of the the factory collection
to be sold and that was one of the requirements, unfortunately, so that's why
it looks like that today.
Now the action on this was very, very obviously taken from the M1 so we have
an op rod, which connects up to a gas port right here in the barrel.
This is a threaded plug, you can take that off in order to have access to the
gas port to clean it. That pin is what holds the gas port--this component--in
place on the barrel, and then we have our gas piston right here that comes
back like so. And then on the underside of that, this was actually driven by a
pair of recoil springs, right there.
Those...
sit in right there, and snap into place, so you've got two of these mismatched
pair of guide rods that gives you spring tension on the bolt carrier and, the op rod
assembly pushes it forward. You can see we have a stripper clip guide up here, so
you have detachable magazines but this can also be reloaded via
stripper clip. Now, in theory, the next step and disassembly would be to pull
out this cross pin here and then this whole trigger and magazine well Assembly
would pivot out of the gun. Again, inspired clearly by the M1, you can see
that this hammer and hammer spring arrangement is very similar to the M1...
just, someone took the M1 and figured, "let's try making a small, handy little
intermediate caliber carbine out of it."
This is sort of like the 8mm Spanish Mini-14, really. The markings on
here are pretty cool,
this is abbreviated, but it is "Mosqueton automatic, caliber 7.92, Model CB-51". Now
that cal. 7.92 tells us that this is an 8mm gun
however, it doesn't describe exactly what cartridge. I am assuming that it's the
standard 8x33 because I know the Spanish did work with that cartridge. It
is however possible that it could be a proprietary 8mm cartridge;
8x30, 8x35, any number of things like that, but I think it's probably the standard 8mm
Kurtz. Now one distinctive element, unique element here is this grip safety.
This has to be depressed in order to fire the gun and it also acts as the
bolt hold open, so you can see this lug right here. When I squeeze the grip
safety, that lug moves up and down. When the bolt is locked back that lug grabs
it, and in order to release the bolt you have to
depress the grip safety. That drops the lug and allows the bolt to go forward. So, as
I showed you, these rifles were made with both short flush fitting five round
magazines and extended larger capacity magazines. I don't know exactly what this
is but I suspect it's 15 to 20 rounds. Now one of the interesting details --"nerdy"
details--here is that the followers are different. These short five round mags do
not use the standard follower, and by the way we have a couple other of these
large mags and all of their followers look the same.
The reason for this, I believe, is that they're copying Sturmgewehr magazine
components. The floor plate looks the same, and this follower looks the same.
Now, if you look at this witness area as I push the follower down, you can see it
move. This tells us that the follower for this magazine is at least, like this long,
which is what you would expect from a Sturmgewehr magazine follower. It had very
long legs in the front and back which made sure that it didn't
tilt under full auto fire when it was feeding. However, if you're going to make
a flush fitting magazine, you can't have a follower that's longer than the actual
magazine body--it simply won't fit.
So what they did on these was make a separate follower--you can see I have to
push it all the way down to the bottom before it shows up in the witness hole
there--well not the witness hole, but the locking lug hole. So this five round
magazine is done that way so that you can actually fit five rounds in a flush
magazine because the standard, stock Sturmgewehr follower wouldn't allow that
to work. One of the other interesting details here, you saw when we had the gun
disassembled, that there were two lines of markings, one small one and then one
larger one.
What's funny here is that the larger line of markings is actually hidden
underneath the stock, I suspect, because this is the only one of these rifles--
there were originally 12 made--this is the only one that has two lines of of
designation markings, and it kind of seems like this was probably the first
one of the batch that got engraved and the guy went through and did the
engraving and then dropped it into the stock and kind of went, "Aw, crap. The stock hides
all that marking."
So he came back and he did a smaller line up here where it would be visible,
and then all the subsequent rifles just have this smaller line. Neat little, you
know, detail that gives you some insight into the foibles of an experimental
rifle production. Now, the most interesting control on this rifle is
this. Its a grip safety, built into the wrist of the rifle and it does function as
grip safety. Unless this is depressed, you can't fire the rifle.
What's interesting is that this is also the bolt release. So, kind of like shades
of the HK P7 right there. When I lock the bolt open like so... the bolt is open,
it's locked in place, I could use the stripper clip guide to reload my
magazine from here, but pulling the the bolt back--the bolt handle back,
it does nothing-- its still stuck in there. Well, there's a little catch connected to this
grip safety, and when I depress the grip safety the bolt drops forward. So that's
an easy way to avoid having an extra control around for the bolt release.
Beyond that, fairly standard features on this rifle. We have our rear sight here,
this is graduated out to 500 yards--or 500 meters, I'm sorry--
and then the hardware on the front of the gun is all pretty basic Mauser
hardware. It looks very familiar.
Interestingly, it has a cleaning rod in it...
however, it's a really short cleaning rod. Its obviously not as long as the barrel.
I believe this is there to serve two purposes; one is that it acts like a
stacking swivel so that a couple of guys can tent their rifles up and
avoid getting them down in the dirt, and the other thing is that this is hollow and
threaded at both--at this end--and of course it's threaded at that end and I
believe the idea would have been you get three guys, or maybe four guys, but I
think three would do, it to all pull their cleaning rods out, thread all three
cleaning rods together, and then you have one full-length rod that all three guys
can use to clean their rifles.
Just one little interesting side effect of this grip safety
I'm noticing that when i'm trying to lock the bolt open, or cycle it and lock it open
just to demonstrate on video, I have to kind of check myself that I'm not
grasping that grip safety, because it's really easy to grip it shut and then try
and lock the bolt open...and you can't. And something that occurs to me is when
you're actually shooting you would be holding this grip safety down, and when
you fired the last round in the magazine it would actually not lock open because
you'd have just fired a round, so you'd be depressing the grip safety, and that
would prevent it from locking open which kind of defeats the purpose of having
the gun automatically lock open when you fire the last round. Just interesting
thought that just occurred to me now while I'm doing the filming. Might
explain why you didn't see something like this on a future experimental or
production Spanish rifle.
Thank you for watching guys, I hope you enjoyed the video, an interesting chance
to look at what one of these, you know, many potential branches of arms design
was after World War Two. So this one didn't go anywhere but, you know, some
others did.
if you enjoy this sort of video please consider checking out my Patreon page
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very long way to help me continue to be able to go out and find really
interesting, exotic guns like this, and bring them to you guys. Thanks for
watching.