What an interesting thread/ read.
Going back to basics of the thread here (compressing air with a spring piston set up for slugs).....this should be possible when you consider one fact-
The projectile in a springer gains the majority of its energy/ velocity while it and the piston are both travelling in the same direction.
With this in mind you can say that stroke length vs barrel length would be a very important factor (dispelling some of the earlier statements that a longer barrel wouldn't be necessary).
Naturally this would scale up everything, including weight and length, which would somewhat help to naturally manage recoil and cocking effort/ leverage.
The downside of course is it also means you could rule out off the shelf options for a suitable rifle (barrels, mainspring, piston, seals) and likley slugs. Pellets are seated in the leade in on a springer, another critical part of their functionality/ efficiency. Slugs are not seated, so as mentioned by someone ealier would likley need to be chambered to allow for initial pressure to build (avoiding losses)
Surely the real issues/ limitations would come with the porting. As swept volume increases the port volume/ flow rates would need to increase too, otherwise the compression ratio would simply be too high. In my head you'd likley reach the point where the port diameter would need to match bore diameter (which may need some thinking about). Short ports flow better, but how short can you physically make the cylinder plug on a springer with all that force behind it
Either way, wouldn't it be great if someone built such a beast and pushed the envelope to find out just exactly where the edge is. Hard to imagine it happening any time soon though.... for the small gains associated with shooting slugs, however.....
Go for it OP! Perhaps its your legacy to be the man who provides this evidence to the airgun nation....one way or the other
Going back to basics of the thread here (compressing air with a spring piston set up for slugs).....this should be possible when you consider one fact-
The projectile in a springer gains the majority of its energy/ velocity while it and the piston are both travelling in the same direction.
With this in mind you can say that stroke length vs barrel length would be a very important factor (dispelling some of the earlier statements that a longer barrel wouldn't be necessary).
Naturally this would scale up everything, including weight and length, which would somewhat help to naturally manage recoil and cocking effort/ leverage.
The downside of course is it also means you could rule out off the shelf options for a suitable rifle (barrels, mainspring, piston, seals) and likley slugs. Pellets are seated in the leade in on a springer, another critical part of their functionality/ efficiency. Slugs are not seated, so as mentioned by someone ealier would likley need to be chambered to allow for initial pressure to build (avoiding losses)
Surely the real issues/ limitations would come with the porting. As swept volume increases the port volume/ flow rates would need to increase too, otherwise the compression ratio would simply be too high. In my head you'd likley reach the point where the port diameter would need to match bore diameter (which may need some thinking about). Short ports flow better, but how short can you physically make the cylinder plug on a springer with all that force behind it
Either way, wouldn't it be great if someone built such a beast and pushed the envelope to find out just exactly where the edge is. Hard to imagine it happening any time soon though.... for the small gains associated with shooting slugs, however.....
Go for it OP! Perhaps its your legacy to be the man who provides this evidence to the airgun nation....one way or the other
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