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70's P*rno

Thread Status: Hello , There was no answer in this thread for more than 60 days.
It can take a long time to get an up-to-date response or contact with relevant users.


Morone saxatilis
Mar 8, 2003
Well not exactly but I need a little more penetration for my bad-vis gun. Basically a jbl 38 special (I don't thik anything is unmolested at this point). I have a threaded 5/16 shaft w/ twin 5/8ths bands (shortened). Anyway this setup will not go through a stripers head at 8'. I won't put any more power on the gun and it's VERY well ballasted (read negative w/ floater wings and shaft out) so the only varriable to play w/ is the shaft size/ head configueration.

Do I go w/ a longer 3/8 shaft (5/16 is 28" so perhaps 32"3/8?) w/ a 3" hawaiian flopper? This would maximize mass while keeping resistance down.

I also have to use a pencil point b/c of proximity to rocks.

I'm also concerend b/c the band stretch is not that long, so accelerating a large heavy shaft my not be the aanswer. I wouldn't mind trying a tiny 28" 1/4" hawaii b/c the speed might be just what the doctor ordered.

Any of you guys who smack lings or grouper up close let me know how you solved this. And any New Englanders should also chime in.

I'm interested in the physics behind 1: head design/penetration and 2: Shaft mass/momentum/acceleration. Now I know how this is all related theoretically but any one w/ too much time and money who could through some quantifiable facts out would be great.
Hi Crown,

Use the search feature and type Metal Tech Zero or MT0.
I have an old post where I have done extensive test on 3 shafts size. Ur 38 is about the size of the MT0, it should help you. As long as that 38 trigger can take at 3 x 9/16" Riffe type of high modulus rubbers, the range you want is do-able. Recoil and consistent accuracy wise I can't say because the MT0 tested was quite heavy for its size, thus more stable. You must experiment a bit here. Forget any shaft less than 5/16" (8mm), at your 38 shaft length it is way too light.

Good luck.


Your gun is about 96cm so has plenty of length to generate the power you need. I'm just going to tell you what works for me for a dirty water setup and maybe this will help.

OMER 71cm MB2000 carbon barrel, Riffe 6.75mm euro shaft hawaiian flopper, 20mm bands loaded to the second notch. I have a 96cm setup exactly the same way but the ease of handling of the 71cm gun in the water has made this my go to gun for Stripers and Tautog around the rocks.

I have had no problem with penetration on Stripers with this setup and the spear has been very durable in the rocks.

Good luck, Guy
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