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A Full Bore PCP Air Rifle

Posted: Sun Sep 19, 2010 6:47 pm
by killerbanjo
Just found this on an old English gun-smithing site that has been shut down for a few years, i used way back machine to recover this though. Anyone ever seen it before?




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Made in the 1940s during WWII, this gun doesn't look like a Girandoni, but examination shows that it clearly was built by someone familiar with the Girandoni repeating airgun system. The story is that this gun was built in Austria by a partisan bicycle maker during the Nazi occupation in WWII.

The repeating magazine is spring fed and on the left side of the barrel, for the convenient use of a right handed shooter. The gun was charged with the accompanying bicycle type pump. Smoothbore, as would be expected, but firing an 11.76 mm lead ball (.463" caliber) the very same caliber as the original Girandoni Austrian military repeating air rifles! This would have been a fearsome weapon against sentries, drivers, military leaders, etc. at ranges up to perhaps 100 yards.

To a freedom fighter, the lower discharge sound and the lack of flash or smoke would have been huge values. And it did not need powder, primers, or bullets—only easily cast lead or soft-metal balls! No forensic evidence left on the shooter (not that they had too much forensic evidence in those days).

The builder surely drew his inspiration from an Austrian museum which displayed a Girandoni system airgun. Note that this gun has a spring fed magazine, rather than the gravity fed magazine of the original Girandoni military air rifle. While a gravity feed mechanism might be simpler, and even more dependable, the spring fed magazine has great advantages for the purposes of this gun. It is more suited for operation from a vehicle or firing slot where it would be impractical to tip up the rifle for loading and it allows firing with minimal motion at the firing point—very important to a sniper. Basic specs: A husky 12.2 lbs., 45" overall, glare-free, and almost camo anodized type finish.

Posted: Sun Sep 19, 2010 7:01 pm
by Gun Freak
Now that is pretty cool! Never seen it before! Interesting find! :)

Posted: Sun Sep 19, 2010 7:18 pm
by POLAND_SPUD
yeah, it has been posted earlier. JSR has mentioned it probably over 400 times

Posted: Sun Sep 19, 2010 11:04 pm
by jackssmirkingrevenge
POLAND_SPUD wrote:yeah, it has been posted earlier. JSR has mentioned it probably over 400 times
#401 ;)

It's in the beeman collection, scroll down :)

Posted: Tue Sep 21, 2010 11:03 am
by FragmentedSanity
Love that gun, Ive looked for more information on it periodically, but the only other reference to it I ever found was the same pictures in crappy black and white.

If anyone has any more details on it, or even care to speculate on what the inner workings look like Id be very interested.

Posted: Tue Sep 21, 2010 12:44 pm
by jackssmirkingrevenge
FragmentedSanity wrote:If anyone has any more details on it, or even care to speculate on what the inner workings look like Id be very interested.
It's a hammer valve combined with an inline magazine, just like the Girandoni - the inner workings of which are described in the link above.

Posted: Tue Sep 21, 2010 8:09 pm
by FragmentedSanity
Ive read that link quite a few times JSR, as well as whatever else I could find on Girandoni's air guns.

I understand its a hammer valve, with an inline mag (spring driven rather than the traditional gravity fed ones of the Girandoni's). Unfortunately things make a lot more sense to me if I can see a picture rather than reading a description.

I understand the concept, its just the execution in that nifty package thats got me confused. I was hoping maybe someone else had found a link not on the beeman site, or had possibly done a sketch up or something. Thanks for the reply tho.

Posted: Wed Sep 22, 2010 6:45 pm
by killerbanjo
FragmentedSanity wrote:Ive read that link quite a few times JSR, as well as whatever else I could find on Girandoni's air guns.

I understand its a hammer valve, with an inline mag (spring driven rather than the traditional gravity fed ones of the Girandoni's). Unfortunately things make a lot more sense to me if I can see a picture rather than reading a description.

I understand the concept, its just the execution in that nifty package thats got me confused. I was hoping maybe someone else had found a link not on the beeman site, or had possibly done a sketch up or something. Thanks for the reply tho.
A simple way to view it is Antonio's airsoft gun take a look here

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linkey: http://www.spudfiles.com/forums/p-4-bb- ... 12216.html

Its not exactly the same as it has a gravity fed mag but you can see the basic function

Posted: Thu Sep 23, 2010 1:32 am
by jackssmirkingrevenge
FragmentedSanity wrote:I understand the concept, its just the execution in that nifty package thats got me confused. I was hoping maybe someone else had found a link not on the beeman site, or had possibly done a sketch up or something.
I'm in a spoonfeeding mood, this is most likely what the internal mechanism looks like based on what I can make out from the external parts.

The bolt is pulled back, exposing the magazine port and simultaneously cocking the hammer that is caught by the trigger. The pin on the magazine is pushed, intoducing a single projectile into the breech, then the bolt is pushed forward again and locked in place.

For firing, the trigger is pulled, releasing the hammer which strikes the valve stem, momentarily opening the valve which allows a burst of air to move through the transfer port and propell the projectile out of the barrel. The cycle can then be repeated.

Posted: Fri Apr 19, 2013 5:34 am
by Flintlock
jackssmirkingrevenge speculated on the internal mechanism of the 1940's "partisan airgun"

Here's my two cents. I think there are several points that do not make sence in the graph"http://www.spudfiles.com/forums/files/p ... ls_906.gif"

First, the bolt doesn't have any practicle use except as a handle to cock the hammer. The designer could simply seal off the back end of the barrel and make a seprate handle for the hammer to achieve the same function.

Second, after the hammer strike, it will stay in the position that pushes open the gas valve causing the gase in the reservoir to empty, wasting most of the gas. this problem, however can be overcomed by using a spring that is slightly shorter than the length of the hammer housing, so the hammer strike the valve with its momentun, and is pushed back afterwards by the valve.

Posted: Fri Apr 19, 2013 7:32 am
by bahur47
Flintlock wrote:
Second, after the hammer strike, it will stay in the position that pushes open the gas valve causing the gase in the reservoir to empty, wasting most of the gas. this problem, however can be overcomed by using a spring that is slightly shorter than the length of the hammer housing, so the hammer strike the valve with its momentun, and is pushed back afterwards by the valve.

This is not true. The pressure in the tank will close the valve back even if the hammer is pushing it - how do i know - my homemade rifle works the same way, also some factory made rifles work the same way (like hatsan at44)

damn i really want some more pictures of this rifle. It looks pretty cool.

Posted: Fri Apr 19, 2013 10:47 am
by mako
This is really a clever design, guys. Correct me if I'm mistaken, but this would be able to fire multiple shots on one charge, because the pressure in the air tank would re-close the valve, yes?

This looks like the perfect method for building an DIY airsoft gun.

Posted: Fri Apr 19, 2013 11:16 pm
by tigerblues28
I realllllly like that design. In fact I'm trying to build a 22 repeater with a hammer valve .
Nick

Posted: Sat Apr 20, 2013 8:39 am
by Gippeto
Mako...you are correct.

Nick...if you posted something more than what your intentions were, someone might be able to help you. :)

Posted: Sat Apr 20, 2013 5:30 pm
by tigerblues28
Oh cry me a river :wink: I'm working on it dude. I'm still working my way around this site.
Nick