Variations on springer pistol design

[tinker]

I like the mechanical aspect of spring guns and one component of that interest is the different design approaches to solve the same problem - have room for a piston and spring and a way to compress the spring. I pulled out some representative samples and took a couple of pictures. 

For those who may not be familiar, here is rundown starting at the bottom left and going clockwise

Diana 6m - the most conventional design with the barrel in front of the compression tube. However, quite interesting in that it employs the Giss system of opposing pistons to make it recoilless for all practical purposes and the easiest to shoot well.

Webley Tempest - barrel over the compression tube with the piston moving to the rear. Allows for a more compact package. Beeman P1/HW 45 is the same design but not nearly as compact.

Cometa Indian - Similar design to the Tempest except that it is a fixed barrel with a cocking lever that pulls the piston forward using a gear and notched strap that you can see coming out of the front in the second picture. Long swing on the lever but super easy to cock.

Walther LP 53 - sleek and beautiful with the compression tube inside the handle. Recoil is a bit odd but capable of quite a bit of power as demonstrated by steveoo.

Hyscore Sportster (803) - very unique design with a 7.7" barrel in that compact package. The barrel actually passes through the middle of the compression cylinder and pellet is loaded directly into the rear of the barrel through a "shutter" type mechanism.

Thanks for reading

tinker

 

[Raden1942]

I'm interested in that Diana 6m. I'll have to do some homework on that recoiless system. Sounds awesome. 

 

[Airgun Advisor]

Gotta love a good spring gun. With time they will comeback in popularity.

 

[PumaCarl]

I had and sold a Diana 6M. Truly stupid of me, and the only airgun that I have ever sold. Seller's regret on that one!

 

[AirNGasman]

Good post, tinker.

I'll just repeat comments I've made too many times in the past to count. In my opinion, handgunnery is one of the most challenging of all shooting sports. And recoiling spring-piston pistols are THE most difficult arms to master to any degree of consistent proficiency.



"springs – where to hide them and how to compress them" 

I try to hide my springs 'where I can't possibly forget where I put them'; which means I'LL DEFINITELY FORGET WHERE I PUT THEM!  And in order to (hopefully) not lose it while trying to compress a spring, I hunker right over the project in hopes when I lose control of the compressing spring it will put my eye out rather than go flying off into the great unknown, never to be seen again (obviously protective eyewear compromises this technique). BTW, I'm not suggesting others utilize this technique.

 

[tinker]

Thanks Ron. That title was rather corny so I changed it to hopefully entice more to have a look. It really is an interesting study. I find that springer pistols are the most fun if I don’t take them too seriously but can also be rewarding to improve. 

 

[Steveoo]

The LP53 can make power, despite what one assumes by housing a power plant squeezed into the grip, because by accident of design they came up with a near perfect compression ratio for its size. I say accident, because I do not think they had the knowledge of Compression ratios back in 1953 when it was designed, but instead put in 2 mainsprings, one inside the other.....their attempt to make the most from the short stroke.

In reality, the duel mainsprings is a bad idea, as the inner mainspring totally nullifies any extra compressive force it has by operating as the worst guide rod ever fitted to an airgun....The key is put in a better single mainspring and then guiding it conventionally...Like so..

Once that is done, the gun then enjoys a nice shooting 500 fps plus. This is because the cylinder volume is actually marginally bigger than the Webley pistols due to its bigger diameter of 23mm x 50mm length versus 20mm x 60mm length....It has a short, direct TP instead of the very long and inefficient 90 degree bend of the Webley....it can completely out gun it.

The Hyscore design, should have been explored more. If you think about it, the barrel can run the full length of the gun, being relatively long, but adding nothing in length as most of it sits inside the power plant. Also, the barrel can then act as the best guide rod in the world (potentially) because the design, using the barrel as the guide rod, runs the full length of the mainspring....unusual to any airgun. The Americans can design good guns....

The Indian was a clever idea but fell out the ugly tree. Pistols, more than rifles, need to be sleek and stylish in the hand, or you lose interest...hence the LP53 is my preference from those shown here.