Mechanical advantage of Spring Guns vs Pneumatic pump airguns

[45flint]

In collecting vintage Airguns in the US you find mostly pump guns. My focus of collecting lately have been prewar spring guns. I have always heard that cocking spring guns is more efficient given pumping of air gives off wasted heat? Has anyone ever calculated the efficiency difference?

[Geezer]

I’m sure that has been done.

This was Jim Tyler’s explanation, though without quantifying how much more efficient a springer is, but suggesting that it’s not all down to heat:

https://www.airgunshooting.co.uk/exp...work-1-5181958

For what it’s worth, a back of an envelope calculation based on the cocking/pumping effort figures in Tom Gaylord’s blog suggests that a typical 12-14 ft-lbs springer requires 30-40 lbs (equivalent) to cock, whereas pumping a Sheridan up to achieve similar power needs more than 200lbs of effort.

[45flint]

I’m sure that has been done.

This was Jim Tyler’s explanation, though without quantifying how much more efficient a springer is, but suggesting that it’s not all down to heat:

https://www.airgunshooting.co.uk/exp...work-1-5181958

For what it’s worth, a back of an envelope calculation based on the cocking/pumping effort figures in Tom Gaylord’s blog suggests that a typical 12-14 ft-lbs springer requires 30-40 lbs (equivalent) to cock, whereas pumping a Sheridan up to achieve similar power needs more than 200lbs of effort.

That is a insane number need to find Gaylords blog.

[Geezer]

https://www.pyramydair.com/blog/2019...reak-part-2-2/

You do the math.

Basically, with most regular 12ish ft-lbs pumpers, the major pump strokes once you get past the first 3 or 4 are each the rough equivalent work of cocking a fairly powerful springer. Even a typical Beeman R1 takes about 40 ft-lbs.

[45flint]

https://www.pyramydair.com/blog/2019...reak-part-2-2/

You do the math.

Basically, with most regular 12ish ft-lbs pumpers, the major pump strokes once you get past the first 3 or 4 are each the rough equivalent work of cocking a fairly powerful springer. Even a typical Beeman R1 takes about 40 ft-lbs.

Fascinating, it’s really the amount of effort it takes at each pump to get a diminishing increase in power. At each pump you have to fight that air volume already in the gun to get even more in? What a stupid system when you think of it. Lol

[cringe]

Fascinating, it’s really the amount of effort it takes at each pump to get a diminishing increase in power. At each pump you have to fight that air volume already in the gun to get even more in? What a stupid system when you think of it. Lol

As I was educated on this forum, don't forget about 'Boyle's Law' cheers Al.

[edbear2]

https://www.pyramydair.com/blog/2019...reak-part-2-2/

You do the math.

Basically, with most regular 12ish ft-lbs pumpers, the major pump strokes once you get past the first 3 or 4 are each the rough equivalent work of cocking a fairly powerful springer. Even a typical Beeman R1 takes about 40 ft-lbs.

Exactly why I had one once.........for about a week.......I personally like the look of some of the earlier USA ones, understand one at least of the (tenuous) advantages mooted about using indoors, but just cannot get my head around why anyone would bother with all the fiddle faddle and nasty plastic and roll pins (on ones I have been asked to repair at least).

Each to their own.......Mine is steel and walnut, quick pull on a barrel / lever....job done

ATB, Ed