6600 shots and change......

Does the Vortek give you a higher velocity than the factory spring?

Interesting Bob ! I really think less air cushion due to elevation creates harsher firing characteristics and more stress on the spring. Didn't you have spring breakage on both your M34's ?

Yes, broke three factory and two Vortek's over the time I owned the two 34's. I feel I did not get my moneys worth out of that 80 spring. If I did my math correctly I only got 25 shots for every dime of the cost of that spring.

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That many broken springs is definitely not a coincidence! Higher air density creates a smoother firing behavior. I took my chronograph to the airgun range at Lake Sonoma and it was 980 ft above sea level. My M34 shot 736 fps with 14.5 gr dome. At my home which is 85 ft above sea level I shoot 750 fps. Could only imagine what you lose.

6000 cycles for a high quality steel spring is nothing. They last for millions of cycles in automobile engines and and suspensions. The spring had an external stress riser, an internal flaw, or was incorrectly heat treated.

6000 cycles for a high quality steel spring is nothing. They last for millions of cycles in automobile engines and and suspensions. The spring had an external stress riser, an internal flaw, or was incorrectly heat treated.

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Your comparing apples to oranges. The coil spring in a springer airgun and coil spring in a automobile suspension are subjected to different dynamics.

6000 cycles is very little for a steel spring.... assuming the engineering is done properly. I wouldn't be surprised if a thorough redesign of the entire springer powerplant by a competent spring engineer would result in significant performance and longevity gains. Are Weihrauch springs shot peened, nitrided or micro polished? These are old techniques used to prevent cracks in engine crankshafts and connecting rods. Maybe a good springer tune should include micropolishing, then shot peening. Reducing mass (lightening the piston) is another must-have because you can then lighten the spring too. it's all about optimization.

Springs are now very high tech. They use conical and beehive springs, friction techniques to prevent harmonics, ovate wire, and extreme care in manufacture. To give you an idea, here's a great article on racing engine valve spring design. 

https://www.enginelabs.com/engine-tech/engine/valve-spring-tech-overview-of-valve-spring-design-dynamics/

"Processing spring wire has become a trade secret for manufacturers. The heat treating and load retention processes are very specific and sometimes proprietary. While the specific techniques may differ, the overall processes reduce surface stress, increase fatigue life, and minimize load loss. Multiple shot peening processes are used in order to induce a compressive stress into the surface of the spring wire. Inducing compressive stress removes tensile stresses that pull the surface of the spring wire apart, creating cracks and leading to failure. Polishing of the spring wire will remove stress risers, increasing valve spring life and fatigue resistance. Finally, heat-treatment processes are critical for minimizing load loss of the spring."

Springs and seals on a piston gun are considered consumables. $20.00 



it doesn't sound like you were using the PG2 kit. Just a replacement OEM Spring?

OP stated it was a Vortek spring in a Vortek kit installed. I had a similar problem with my HW97K breaking a lot of Vortek springs from a Vortek kit. Some of the Vortek springs just do not last that long. It might be just a bad batch of springs Vortek is using. Anyways, if you shoot a springer a lot, the spring will eventually break especially at the tight fitting top hat area.