Did DC hit 200 fps @ 10GPP after all??

[Badger]

Alan, I should probably ship the bow back to you.

[simk]

95% of the time there is a testing issue with high speed claims.

Thanks Alan for being critical  ..and getting me off my comfy couch!
I checked my shooting machine again - and of course the drawlength wasn't set according AMO standard. It was measured from the pivot point what means my measurings weren't "shy under 28" but pretty percise 29" drawlength. All other variables were correct. The speeds in fact were measured @ 9.2gpp, not 10gpp (taken in account higher drawweight at 29").
I'm still very happy with these longbows which I did not design for max. speed. I will maybe make one with heat treated belly laminates; seeing some more potential in there.
cheers

[mmattockx]

Mattock,, the bow was about 54 inches,, sometimes when trying to do that,, some of the reflex pulls out and its a wash,, shooting about the same,, but you could be right,, I think a little longer bow would hold the 28 draw a bit better,, since my draw is about 25 or 26,,

I think you're right on a bow that short. I always make mine around 66" and I draw close to 28", so they have some draw length leeway, but that one is designed around your draw and probably should stay that way.


Mark

[bradsmith2010]

   Mark, sometimes I am shooting the bow through the chrono as I tiller,, and an increase in draw usually increases the speed, if I tiller it out another inch and no speed increase,, I know im not gonna get much more,, if any,,,kind of readched the limit of the bow,, then I keep in mind where that happend and design my next one accordingly,, I have pushed the limit on some longer bows even to 32 inches,, but the speed doesnt go up as much as you would think,,
maybe if I adjusted the proportions,, but as we know,, getting to 180 and above is pretty tricky,, when I make a bow for my draw,, say 25 inches and its in the 170 or high 170,, I feel pretty good about,,it,,
   these are mostly sinew backed,, I made a bow for Jeffer,, and his draw was close to 29 inches,, the stave was great and had some reflex,,self bow, it was close to 180 fps,, arrow little lighter than 10gpp,,, ok looked at my notes,, shot it at 28 inches about 56# and 512 grain arrow,, 181 fps,, I think thats my best self bow I tested,,I never tested it at 29,,, it was not heat treated at all,, no corrections,, just like the stave came out,, osage

[willie]

I believe this bow was a legitimate 200 fps at 28” draw with 10ggp arrow bow. I very carefully followed how the bow was tested, asked many follow up questions, and I couldn’t find any obvious issue to say otherwise.  I couldn’t find any fault with DC’s bow.  I consider DC’s 200 fps bow legitimate and an incredible achievement!

Alan

Alan
How was the28"  drawlength measured? AMO? to back of bow?   


@all
was there a spec to measure the 28" in the original challenge?

[bradsmith2010]

thats a good question,, I think I remember to the back of bow,, but Alan or Steve would know for sure

[avcase]

Alan
How was the28"  drawlength measured? AMO? to back of bow?   

[/quote]

I recall feeling pretty confident that DC’s bow ended up meeting the AMO standard, which is a draw of 26-1/4” from the deepest part of the grip.  However, I think the test specifics were spread out over a number of different posts. There was a lot of checking and rechecking and refinement. For example, rechecking the chrono used by shooting through two chronographs at once, refinement of a shooting fixture, etc.

It is unfortunate that the AMO standard adds a 1-3/4” offset to a 26-1/4” draw length, and then calls it a 28” draw. We don’t do this with our measurement of brace height. This has led to endless confusion over the years.

[avcase]

Alan, I should probably ship the bow back to you.

Steve,
It would be cool to see what this could do if systematically matched to a set of new top notch flight arrows.  It takes some time to do all this, but it would be pretty cool to see the full potential.

[bjrogg]

Glad to see this post.

I’ve been thinking about DC lately and wondering how he’s been.

He added a lot to this site.

If your out there DC I hope all is well

Bjrogg

[DC]

Thanks BJ, I think about you every time I have a can of Bushes Beans. I'm doing well. Alan contacted me yesterday and said my name had popped up here. Well, I couldn't resist poking my nose in. I think the "Quest for 200" just burned me out and I just got to the point where there was no interest in making bows any more. I tend to do a hobby for about ten years and then move on. My last ten or so bows hovered around 195-200 and I couldn't tell from one to the next what the difference was. When you're aiming a 1 fps gain there ain't much difference. Every bow was a crap shoot and i was just accumulating more and more bows that never got shot. The SCA group would take some but then I would have to re-tiller them to be 30-35 lbs and that was kind of defeating. There's still 48 bows hanging in my hall. As for the 200fps@10gpp I do believe that I made about 4 or 5 that Were honestly in that range. I'm waiting patiently for Tuomo to test the one that he has just for a little confirmation No pressure Tuomo
Steve, there is no point in sending the bow back to me. It would just join the others on the wall. I remember giving it to you in one of our last conversations so it's up to you, but it would be nice to see Alan mess with it. Maybe Jordan would want it. I was pleased to see that the record she set with it held this year. It's my 15 minutes of fame. I have a copy of the results out in my shop and I look at it every so often.
Anyway, I took up model ship building. I'm scratch building a model of George Vancouver's Discovery. While I was making bows I cultivated some Hazel suckers for bows and when I quit making bows and took up boats I harvested the Hazel and used it to make the ship. I've been working on it for just over a year and I'm maybe halfway. At least ships don't pile up in the corner as fast as bows did.
So that's it from me.
Don


Oh Mark, how did those bows I sent you work out?

[bjrogg]

Great to hear from you DC. Sure glad you’re still eating bush beans.

Totally understand where you are coming from

I’m a lot that way myself

Would love to see your model ships in the campfire section.

Take care and Happy Holidays

Bjrogg

[mmattockx]

Oh Mark, how did those bows I sent you work out?

They are safely stored for the moment. All my arrows have vanes so I have to pick up some with fletching and I've been so busy with the new house and acreage yard projects I've hardly shot anything the last year. Next summer will change that, with the house and basement done and a decent little archery range area set up. Once I get a bow rack done I will definitely be hanging a few there for people to see, they are just too nice not to admire regularly.


Good to hear you are still doing well,
Mark

[DC]

Great to hear from you DC. Sure glad you’re still eating bush beans.

Totally understand where you are coming from

I’m a lot that way myself

Would love to see your model ships in the campfire section.

Take care and Happy Holidays

Bjrogg

All my pictures are too big. Maybe look here
https://shipsofscale.com/sosforums/threads/hms-discovery-1789-scratch-build-in-1-48.8325/

[DC]

Oh Mark, how did those bows I sent you work out?

They are safely stored for the moment. All my arrows have vanes so I have to pick up some with fletching and I've been so busy with the new house and acreage yard projects I've hardly shot anything the last year. Next summer will change that, with the house and basement done and a decent little archery range area set up. Once I get a bow rack done I will definitely be hanging a few there for people to see, they are just too nice not to admire regularly.

Good to hear you are still doing well,
Mark

Good to hear Mark

[bradsmith2010]

DC great to hear from you,, happy holidays,,