Crazy Italian Hoist Spearguns!

[Slingador]

Bump. Would love fresh input from folks that have used these for awhile. In time have they worked out? Amazing designs, thanks for sharing

 

[poildeq]

I love the unfathomable creativity of those ppl well done

 

[sharkey]

I had a gun over twenty years ago which used two eccentrics off a compound bow located behind the handle. It only used rubbers which were about 30mm long as most of the "pull" was from the eccentrics rolling over. The gun had 50% "let off" as it became easier to load as it was drawn back, just like a compound bow. The draw was only about 200mm but it could be increased or decreased by changing the size of the eccentrics. It was a novelty but the concept is sound & by using springs instead of rubber it would be possible to make a gun which never needed to replace rubbers. Also as the "power pack" is compact & near the handle, a very manoeuvrable gun could be produced as the barrel only needs to support the spear & hold the shooting line, not resist the rubbers.

Cheers Sharkey

 

[poildeq]

I had a gun over twenty years ago which used two eccentrics off a compound bow located behind the handle. It only used rubbers which were about 30mm long as most of the "pull" was from the eccentrics rolling over. The gun had 50% "let off" as it became easier to load as it was drawn back, just like a compound bow. The draw was only about 200mm but it could be increased or decreased by changing the size of the eccentrics. It was a novelty but the concept is sound & by using springs instead of rubber it would be possible to make a gun which never needed to replace rubbers. Also as the "power pack" is compact & near the handle, a very manoeuvrable gun could be produced as the barrel only needs to support the spear & hold the shooting line, not resist the rubbers.

Cheers Sharkey

Sharkey

any pictures of this contraption?

 

[sharkey]

Sharkey

any pictures of this contraption?

No photos I know of, but I'm sure that I still have the eccentrics & the basic parts in a shed out on the farm. It wouldn't be hard to remake a basic compound speargun. Take a look at how a compound bow works. A compound speargun is not that much different to a roller gun really, there is just eccentrics which roll over as the gun is loaded, instead of rubbers doing all the work.. These eccentrics & their diameter, are what gives the length of pull as they roll over, instead of stretching rubbers. The larger the diameter of the eccentrics the longer the draw length/throw. My gun had eccentrics off a 65lb compound bow if i remember correctly. They were about 80mm in diameter & gave about 200mm draw/throw. My old gun used two very short rubbers (30mm) for the power. One end of the rubbers was attached near the butt, the other end to the eccentric, to give them their energy. The eccentrics were fixed to the gun by an "axel" about 150mm in front of the attachment point for the rubber. As the eccentrics rolled over they stretched the rubber & gave the draw length to load the cable into the standard spear notch. The loading cable needed to change direction 180 degrees just like in todays roller guns, however it was only 300mm infront of the loading notch on the spear not at the muzzle. This compact "power pack" & short pull could really change the way guns are made & I'm surprised we haven't seen a "compound speargun" on the market yet, even just as a novelty like my old one was.

Looking forward to see if anyone is going to make one of these, & what they do with the barrel to support the spear & shooting line as this can now be made much lighter.

Cheers Sharkey