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    • James Harvey
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        Post count: 1130

        I have a samick sage with 40# limbs and have just had a look at seeing if I could tune an EFOC arrow to it with the bits and pieces I have in my garage.

        I ended up with a 300gn head, 75 grain adaptor, standard Al insert, on a 32 inch 340 MFX Classic. This freight train works out to 818 grains, 27% FOC and a whopping 19gn/pound of bow.

        ‘Well, that was fun,’ I thought to myself. ‘But that’s just too much mass for this little bow to push through the world.’ Three shots later and that one shaft went straight through my backyard target. To put that in context, a 600gn shaft at around 14% FOC from my 70# Barta bow has never gone more than about 12 inches deep into the 18 inch deep target.

        So I’ll take this arrow and bow to the local range this week and see if it can stay air born for more than 10 yards 😉

        Anyway, these results were beyond my expectations and I thought they were worth sharing. Even if this arrow is too heavy, imagine what you could achieve with a low GPI 400 spine shaft for your little bows. Pretty cool.

        Jim

        PS

        The bow is 40#@28″, had a fastflight string braced at 8″, I draw it to just over 29″, so about 42-44#.

      • David Petersen
        Member
          Post count: 2749

          Jim, that IS impressive and dramatically confirms Ashby’s experiments, and reports, that arrow mass and EFOC make even more difference in penetration with lighter bows than with heavy (the percentage of gain is much higher). Are you saying you haven’t shot it from 20 yards yet to check trajectory. That could well be the downside. Let us know.

        • Bruce Smithhammer
            Post count: 2514

            EFOC – confounding conventional assumptions yet again! Let us know how they fly at longer distances.

          • James Harvey
            Member
            Member
              Post count: 1130

              Yeah Dave, my backyard range is only 10m. I’ll let you know how it goes.

            • David Petersen
              Member
                Post count: 2749

                Well, Jim, if the layout is right you could open the back door and shoot through the house, considerably lengthening your distance. 😛

              • Ralph
                Moderator
                  Post count: 2580

                  May not have to worry about distance. May just go “plop”. Bury up deep! :lol::lol: Fun playing ain’t it Jim.

                • David Coulter
                  Member
                    Post count: 2293

                    Ausjim,

                    There’s one fellow on here that gets 25 yards INSIDE his apartment… but then he’s a jazz musician, too. Good luck with that arrow, dwc

                  • James Harvey
                    Member
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                      Post count: 1130

                      Well, I shot it at twenty metres and didn’t really see where it landed so went out to the target to have a look. When I got there I heard a thunk and there it was! Talk about slow…

                      Another remarkable feature was that it was point on target at 20m (it is a long shaft, the point is a lot further out there). So well and truly on the way down by 20m.

                      I guess the little bow was a little worn out by the weight of it all. I’d still be keen to see what could be achieved with a softer, low gpi shaft and something more like a 250 or 300gn head. Alas, its back to the longbow and some stiffer shafts 😀

                    • Ptaylor
                      Member
                        Post count: 579

                        ausjim wrote: Well, I shot it at twenty metres and didn’t really see where it landed so went out to the target to have a look. When I got there I heard a thunk and there it was! Talk about slow…

                        😀

                        Jim, watch out you don’t shoot yourself in the back:lol:

                      • gigglemonk
                          Post count: 146

                          I’ve put my 53# bow away and been shooting a 44# one. 675gr arrows with 19% FOC. 200grain hex heads and meatheads. I e only been getting bunnies but my effective range is 30yards. As for speed, I got a bunny running straight away from me on Wednesday night. Paced it off at 23 yards. Seems fast enough for me!

                        • James Harvey
                          Member
                          Member
                            Post count: 1130

                            Giggle, I was super impressed with everything about my little experiment except how mind bogglingly slow it was. Troy Breeding said in another thread he’d take quiet over fast any day, and it was certainly super quiet (for obvious reasons). I have some 70# sitka spruce shafts that are showing promise with a 300 grain point for my little bow. That’d work out to similar shaft stats you’ve given above. You’ve given me a little hope for my little bow!

                            I’d love to attempt some real world penetration with a setup like that. Maybe it’s time for a trip to the butcher 😀

                            Preston, if anyone could manage to shoot themselves in the back with a bow it would be me 😉

                          • Etter1
                              Post count: 831

                              I’d say worry more about your accuracy than FOC. It would be hard to shoot an arrow accurately if it drops 6″ every 5 yards.

                              Love hearing about the experiments though.

                            • James Harvey
                              Member
                              Member
                                Post count: 1130

                                Etter, I did a little experiment the day I was out there shooting that whopper of an arrow. Once I had more or less figured out my ‘gap’ for that shaft, I shot the unfletched arrow using gap aiming at 20m. Then I moved a few metres to the left (so as to avoid any unconcious reference to the POA I just used) and shot an identical, fletched arrow instinctively (noting that my ‘instincts’ are not at all tuned to this bow/arrow combo).

                                My ‘bullseye’ in this shot is the white disc (the insert from a gatorade bottle cap) stuck on the coke bottle just left of the unfletched shaft.

                                Obviously instinctive shooting is going to require a lot more practice to have confidence, but if you gap, it’s just a matter of finding your point of aim at a few different distances and then an accurate judge of distance. With a bow/arrow combo like this you’d obviously need shorter intervals between your known Points of Aim. But I agree, for this little bow I’d be more comfortable with a lighter gpi setup that delivers a bit flatter trajectory 🙂

                              • Etter1
                                  Post count: 831

                                  That’s pretty impressive Jim. Shooting any unfletched arrow requires some great form on your part!

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