Page 1 of 2 12 LastLast
Results 1 to 15 of 25

Thread: Restoring an antique strike-pump air gun

  1. #1
    ccdjg is offline Airgun Alchemist, Collector and Scribe
    Join Date
    Jun 2007
    Location
    Leeds
    Posts
    2,039

    Restoring an antique strike-pump air gun

    I had always wanted a real antique airgun but could never afford the sort of prices asked. Then a few years ago on a visit to Henry Kranks gun shop I spotted a 200+ year old air rifle which was on offer at a very affordable price, thanks to the fact that it didn’t work and it had had some poor restoration work done to it. The dealer said that it was probably a bellows air rifle, and as they had a problem getting it apart in the shop I had to take a gamble and buy it as seen. It might have had no mechanism inside , so it was a bit of a risk, but at £900 it seemed to be worth a punt, especially as externally everything seemed to be original, except for the brass cover plate on the stock.






    When I got the gun home I managed to get the brass plate off, after the application of some penetrating oil and localised heating from a soldering iron to the rusted-in screws. When the mechanism was exposed, I was surprised to find that the gun wasn’t a bellows rifle after all, but was what is generally referred to as a “strike-pump” air rifle, which are in fact rarer. They have a spring piston power unit in the stock, which is usually cocked by turning an axle, which in turn pulls back the piston by what closely resembles a bicycle chain.
    When I removed the power unit it was clear that the reason why the gun would not cock was that the piston had seized in the cylinder. This was eventually freed and the disassembled unit is shown here. Everything about the unit is huge: the piston head is an inch thick cylinder of leather, the massive spring is made of roughly quarter inch square section steel, and the very long air transfer port has a diameter of about a centimetre.









    After several attempts to cock the gun, it soon became apparent that the forces involved in compressing and holding back the mainspring were causing the stock to disintegrate where the sear and cocking unit was bedded into the wood. The damage can be clearly seen with the brass cover plate and heel plate removed:











    I decided that if I was ever going to get the gun into a workable condition I would have do some serious reinforcement work on the stock. I always hesitate doing any restoration on really old guns, but in this case there had evidently already been bodged attempts at shoring up the woodwork in the past, so I felt that I would only be improving things cosmetically, and would also be helping to make the gun useable again.
    Old crumbling wood was scraped away, and the cavity was built up using shaped pieces of walnut glued in place with epoxy resin. Small gaps were then filled with walnut stained plastic wood. This was the result:


















    The brass plate that covered the mechanism aperture was clearly a later addition and had been made much larger than the original plate to give more support to the crumbling wood underneath. In fact the original plate was still in evidence , but had been brazed to the underside of the new plate, presumably to provide more rigidity and to help locate the screw holes. The rectangular shape of the new plate was out of keeping with the general character of the gun, the original having scalloped edges similar to the plate on the other side of the stock. So the plate was reshaped with a fine saw and a file, giving something much closer to how the original would have looked:


    The wood was then inlet to accept the newly shaped brass plate:







    This how the left and the right side of the stock now look:










    The gun has some nice features. There is a built in option of open sights or a peep sight. The peep sight is adjustable for height and windage:





    Alternatively, the peep sight can be dropped to its lowest position so that the open sights can be seen. The rear sight blade has a nice touch in that it is hinged and so has vertical adjustment, as well as the usual dovetail windage adjustment.




    For loading, the barrel is spring-lifted by pushing forward the lever in front of the trigger guard. This system differs from most bellows air rifles of the period, which generally relied on the natural flexing of the wood frame to lift the barrel rather than using a leaf spring.






    The bore is a massive 9 mm, so in order to try out the gun I had to make a suitable dart (these guns were only ever intended to fire darts, or possibly wax balls). The large bore size can be best appreciated by comparing my home-made dart with more conventional commercial darts.





    Firing the gun is quite an experience. Firstly, using a long wrench to grip the square section crank peg, this is turned about half a revolution to wind back the chain until the sear engages. This takes a surprising amount of effort, reflecting the excessive stiffness of the mainspring. The barrel is then opened and the dart inserted. The rearmost trigger is pulled back until a loud click is heard, which indicates that the hair trigger has been set. A light touch on the forward hair trigger then fires the gun. The report is loud and the recoil quite pronounced, thanks to all that heavy metal, made up of the piston, piston rod and crank chain, hurtling forward at high speed and then crashing against the cylinder end. However, the power output does not match the spectacular cocking effort, thanks to the dead weight of the piston/chain assembly, the large air transfer port and the poor barrel seal unit, but it is adequate for indoor target shooting. An efficient shooting machine it is not!
    I reckon that the gun would now retail at about £2000 -3000 judging from recent auction and dealer prices, which makes my £900 a good investment after all.

  2. #2
    Join Date
    May 2017
    Location
    Ormskirk
    Posts
    194
    A wonderful job you have done bringing a piece of history back to life thanks I enjoyed reading that mike

  3. #3
    Join Date
    Mar 2006
    Location
    City of London
    Posts
    9,735
    Incredible work, John! Interesting mechanism. It's almost a 'spring piston' gun with a floating compression chamber, I suppose. Not such a great conceptual leap from there to modern airguns.
    Vintage Airguns Gallery
    ..Above link posted with permission from Gareth W-B
    In British slang an anorak is a person who has a very strong interest in niche subjects.

  4. #4
    Join Date
    Feb 2006
    Location
    Farnborough
    Posts
    4,394
    Wow, what a fascinating rifle and resurrection! Great work

    At first the bang sounds excessive for the output but then I start wondering, is it deliberate? Was it intended to replicate the recoil of shooting a powder burner of the same era? Whatever the intention it's great to see her working again.
    WANTED: Next weeks winning lottery numbers :-)

  5. #5
    Join Date
    Feb 2001
    Location
    Winchester, UK
    Posts
    15,343
    Very nice bit of necessary restoration work, John. Good to see an old timer brought back to life.

  6. #6
    Join Date
    Apr 2001
    Location
    Wet Cold Downtown Leicester
    Posts
    18,523
    Fascinating work

    Well done
    A man can always use more alcohol, tobacco and firearms.

  7. #7
    Join Date
    Mar 2009
    Location
    durham
    Posts
    3,454

    Restoring an antique strike-pump air gun

    You've certainly eared any profit you'd make selling that one, great restoration , well done!
    Last edited by junglie; 12-03-2018 at 06:08 PM.

  8. #8
    Join Date
    May 2011
    Location
    Saxmundham
    Posts
    1,504
    Thank you for an interesting post and even better photos. Why are they called a strike pump? Your fine old air rifle works using a piston to compress air and blow the dart down the barrel or have I misunderstood how it works?

  9. #9
    ccdjg is offline Airgun Alchemist, Collector and Scribe
    Join Date
    Jun 2007
    Location
    Leeds
    Posts
    2,039
    Quote Originally Posted by greenwayjames View Post
    Thank you for an interesting post and even better photos. Why are they called a strike pump? Your fine old air rifle works using a piston to compress air and blow the dart down the barrel or have I misunderstood how it works?
    That is a very interesting question and one that I don't really know the answer to. You are right in that the system is basically what we would call now a spring piston mechanism. The term "strike pump" seems to have been coined by Arne Hoff in his 1972 book "Airguns and other pneumatic arms", and he has a whole chapter entitled "Strike-pump Guns". Wherever it came from, the term has now come into general use (especially by auction houses) as a descriptor for very early spring-piston airguns where the cylinder is concealed within the stock. It is also popularly used in Germany, as "Schlagpump".

    If anyone knows of any use of the term before 1972 I would be very interested to know.
    Thanks,
    John

  10. #10
    Join Date
    Jan 2016
    Location
    Wooster
    Posts
    3,513
    That is something special, fine work. Reminds me of the fine brass inlay work done on flintlock rifles in this country. Something I’ve always admired.

  11. #11
    Join Date
    Feb 2007
    Location
    Moreton in Marsh
    Posts
    816
    Thanks for such a great post. It made my morning commute bearable!

  12. #12
    Join Date
    May 2011
    Location
    Saxmundham
    Posts
    1,504
    Quote Originally Posted by ccdjg View Post
    That is a very interesting question and one that I don't really know the answer to. You are right in that the system is basically what we would call now a spring piston mechanism. The term "strike pump" seems to have been coined by Arne Hoff in his 1972 book "Airguns and other pneumatic arms", and he has a whole chapter entitled "Strike-pump Guns". Wherever it came from, the term has now come into general use (especially by auction houses) as a descriptor for very early spring-piston airguns where the cylinder is concealed within the stock. It is also popularly used in Germany, as "Schlagpump".

    If anyone knows of any use of the term before 1972 I would be very interested to know.
    Thanks,
    John
    Thank you for the reply. I will have to look out for Arne Hoff's book. Xmas is a long way off but I have a birthday before that

  13. #13
    micky2 is online now The collector formerly known as micky
    Join Date
    Jan 2016
    Location
    boston
    Posts
    2,139
    What a very good job you have done on restoring a antique airgun not an easy job, and putting it back to more like it's original state brass work. and working order again.

  14. #14
    Join Date
    May 2011
    Location
    Saxmundham
    Posts
    1,504
    Quote Originally Posted by ccdjg View Post
    That is a very interesting question and one that I don't really know the answer to. You are right in that the system is basically what we would call now a spring piston mechanism. The term "strike pump" seems to have been coined by Arne Hoff in his 1972 book "Airguns and other pneumatic arms", and he has a whole chapter entitled "Strike-pump Guns". Wherever it came from, the term has now come into general use (especially by auction houses) as a descriptor for very early spring-piston airguns where the cylinder is concealed within the stock. It is also popularly used in Germany, as "Schlagpump".

    If anyone knows of any use of the term before 1972 I would be very interested to know.
    Thanks,
    John
    Arne Hoff doesnt sound like an English name. Do you think something may have got lost in the translation? Perhaps strike pump is the name given to spring piston guns in his native language? Only a thought.

  15. #15
    Join Date
    Jul 2012
    Location
    Portland, Oregon
    Posts
    725
    Quote Originally Posted by greenwayjames View Post
    Arne Hoff doesnt sound like an English name. Do you think something may have got lost in the translation? Perhaps strike pump is the name given to spring piston guns in his native language? Only a thought.
    Hoff is Danish.

    At the intro of chap three, Hoff explains how he came to use the term "strike pump."

    'Systematically different from the bellows gun is a type which is generally called a spring gun, where the momentary air pressure is created by a spring-propelled piston rushing forward in a pump-cylinder. The term spring gun is rather unsatisfactory as it ought to indicate a gun where the projectile is expelled by the direct action of a spring. In the following, the gun with spring-propelled piston will, therefore, be called strike-pump gun.'

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •