You might find this interesting?

steven in England · Post by **steven in England** » Fri Aug 27, 2004 6:54 am

www.thudscave.com/npaa/articles/howhard.htm

Steven

Woodsman · Post by **Woodsman** » Fri Aug 27, 2004 7:45 am

...interesting.

...an in case no one knows what an atlatl and dart is:

http://www.atlatl.com/

RWK · Post by **RWK** » Fri Aug 27, 2004 2:26 pm

To change the subject how are you feeling after your trama. Going well i hope. Good luck Rich

GaryL · Post by **GaryL** » Fri Aug 27, 2004 2:36 pm

Yeh steven in England how are you doing now

wabi · Post by **wabi** » Fri Aug 27, 2004 3:05 pm

Interesting!
I've been seriously thinking of trying an atlatl. (for target practice & "stump shootin') I read an article in the latest issue of "primative archer magazine" about them just last night.

striper · Post by **striper** » Fri Aug 27, 2004 3:38 pm

Steven: I sure am glad you stuck that bolt in your butt and not in your head.

Do you think Bill T. will offer the atlatl? We could call the low velocity one the Mammixen. We could call the most powerful one the Maxomam. Just kidding. I am happy you have got to the point you can address the weighty problems of life. Welcome Back!!!!!!!!!!!!! Striper

steven in England · Post by **steven in England** » Fri Aug 27, 2004 7:35 pm

Thanks for the well wishes. Just got my stitches out today, still in a little bit of pain but moving quite easy now. I have been told it may take up to a couple of months for the muscle which was cut to repair. Hope to be cocking my crossbows again before that. Had allot of time to weigh some different weight bolts up to try. Bill T had a 1200 grain bolt if he ever had an opportunity to shoot elephant, so I have weighed some up myself but have ended up with 1480 gains with the broadhead on to get a good balance with a stiff spine. I think they will fly good and expect 190 fps, if momentum does predict penetration rather than k.e I think they will take some stopping. These bolts are obviously no use for anything but I get a kick out of testing different thing out. The accuracy of Excalibur with normal bolts is just too good so I thought I would try and see how other weights and different bolts, spine would fly.
Steven

chris4570 · Post by **chris4570** » Fri Aug 27, 2004 7:56 pm

[/quote]Sectional density is why the arrow passes through the sand, the bullet is stopped by it, and the baseball bounces off. [quote]

Is this the real reason? I'm no scientist but my guess as to why a .357 Magnum will not pass through the sand has more to do with the bullet expanding/mushrooming as it enters the dense substrate than with sectional density (does this change the sectional density?). I wonder what type of bullets were used in this experiment, hollow-points, wadcutters, full metal jackets, armour piercing, etc. And if you were to put a blunt on the end of the arrow would that arrow still pass through the sand?

GaryL · Post by **GaryL** » Fri Aug 27, 2004 8:43 pm

No chris4570 a blunt would not

Quote "To settle it (and to find out which was nearest the truth), I sat down and made some calculations about different projectile weapons, including atlatl darts. In the end, I came up with three variables for comparison -- how hard it hits (kinetic energy), how hard it is to stop (momentum), and how effectively it penetrates (sectional density). "

sectional density in his example, I take it as meaning how sharp and pointed it is.