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The guns may be becoming an "orphan" and the resellers are simply unloading them. At under 200 dollars they are reasonably cheap and should give no trouble for a year or two. The 50 cm at 165 dollars is only OK if you want a variable power gun, but guns like the single power Salvimar “Vintair 50" (or the Scorpena V, same gun) can be had for a lot less in 50 cm size. 175 bucks for a 75 cm is about par for the course, but importantly the gun comes with an 8 mm stainless steel screw-on tip spear which is what you want for hitting power down range and around rocks. A Cressi-SUB SL70 is about 280 dollars for a similar gun, but has a lot of service history being sold for decades. I did not buy the 100 cm as I already have a Predathor 100 cm gun.Just noticed the same gun for sale at Pinnacle Dive Australia, on the Gold Coast, for $165 - 50cm, $175 - 75cm, and $185 - 100cm. Not selling parts though...
Here are some photos taken while swatting away the pesky Australian bush fly which descends on us in summer in large numbers.
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Note that the gun comes with a detachable tip with a connecting cable and not an integral tip, which is good as many guns seem to have gone Hawaiian or Tahitian when that is not necessarily what you want.
Here is a monotube pneumatic speargun, the Nemrod "Torpedero" from the fifties. Not Nemrod's first pneumatic gun, it is a forward latching gun with a form of spring gun trigger mechanism installed in the muzzle which is operated by a slide trigger in the mid-handle using a pull rod. This is actually the layout used by the earliest pneumatic spearguns, but they had a longer pull rod placing the handle further back in a rifle shoulder stock arrangement.Earlier on this thread I queried the low power shot being 2/3rds of full power, but if the rear chamber or pre-chamber is much smaller than on say a Mares gun then it could be that the compression ratio on low power is 10. If we look at the high power-low power graph we can see that low power would then be about 1/3 using the area of the compression ratio curve bounded by the purple rectangle.
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Note that in the previous graph for a Mares gun we assumed the compression ratio for low power was 5.0 and therefore used the curve shape enclosed in the green rectangle. (see below) On these guns low power is approximately half power.
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Just to refresh memories if we took a gun and translated its tank volume to a long tube of the same diameter as the inner barrel and fixed it to the end of the inner barrel then we would have converted the gun to a very long monotube which these graphical analyses are based on. The reason why pneumatic guns have fat diameter tanks is to shorten them, otherwise guns would be very long and unwieldly (which once they were in the distant past).
Based on this analysis the Eskwad gun would need to have a larger pre-chamber for it to obtain 2/3rds on low power, which it does not appear to have on the existing schematic diagram.
P.S. Just reading the advertising again it says "the power reduction system allows a reduction of 2/3 of the power." So it looks like the power left is a third which would fit in with what has been demonstrated above.
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