Here is a quick vid of what happens when one of our standard steel tipped ballista bolts  connects  with a Vietnam era, US GI steel pot helmet.    20100323153608(1)

As can be seen in the photo below, this bolt blew a  1  1/8″  hole through the helmet.    After exiting the helmet the shaft snapped off,  but not before it had sunk the entire 7″ length of quadrobate steel tip into the pine backstop.  While this shot did not quite exit the pine block,  the previous attempt on the Foster’s lager  penetrated through the log by a couple of inches.  The distance here is a very short 15 yards.  These tests will all be repeated at longer ranges as Firefly becomes more developed.

What correlation there may be between a relatively modern piece of armour,  and a piece that would have been in use during Roman times,  is not something I know much about.  However, with this much over-penetration,  it seems doubtful that an ancient warrior could lug around enough conventional armour to have any real protection against these nasty little darts.

One Response to “Firefly and the armoured airhead.”

  1. Captn Harpoon says:

    Todays Warhammer1 blog entry…(500fps goal)

    March 28 – a little more tweaking today with some results. Yesterdays testing gave me 168fps (best) with about 38lb pull with new accelerator feature(4.4 fps per lbs of pull), and 158fps without accelerator feature (4.15 fps per lbs of pull).

    After a little re-work I got 120fps with just 25lbs of pull or 4.8fps per lbs of pull. This is significant in that the new “accelerator feature” was not used but effeciency increased all the same. Adding another 25 – 50 lbs of pull at this point can only be a good thing.

    Todays 25lbs of pull in total had to power a 20 Beman carbon fibre arrow with 125 grain field tip, plus the heavy 3/8″ metal rod “limbs” or levers – about 14 inches in total. Adding another 25 lbs of pull to bring the total up to 50lbs I feel would result in a speed of at least 200fps, perhaps as high as 220 – 230 fps.

    This is not to say that at 100lbs of pull I will be able to obtain speeds in excess of 400fps, but if that were so 500fps would seem an easy task. More than likely a pull of 100lbs would result in speeds of around 300fps, maybe a little more. It does seem reasonable (given todays results of 4.8fps per lb. of pull) that at 150lbs pull, speeds in excess of 400fps is entirely possible. Since Nicks Orsova design (Firefly) has already hit 401fps, the new performance bar should be raised to 500fps as a lofty but attainable goal.

Leave a Reply