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Post by Doegirl on Feb 7, 2009 19:46:57 GMT -5
Today I had some free time to play with the "javelins"  I needed to get a new release, so off to the proshop. My arrows weighed in @ 668grains. Speed clocked in at a blazin' 190fps ;D I'm just glad I got that kind of speed. We also chrono'd the arrows I used last year in Westchester. They weigh 300grains on the nose and chrono'd at 285fps. I've lost 105fps  Anyways I head over to the archery club. It was pretty windy and that new release had me a little edgy (trigger set too light). Regardless, I observed no flight problems from those big old grizzlies. I just got an initial sight in at 20yds. Best I could muster was a 2" group. But that was mostly due to the nut behind the bow   The arrow drop difference between a 300grain, 402grain, and 668 grain arrow. The 668 grain arrow had to be pushed back out of the bale to take the photo:  The wind was really challenging, but the broadheads tracked true:  |
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Post by BT on Feb 7, 2009 20:35:46 GMT -5
Thats looking like a tracking group (s to drop) did you measure the distance between the top and bottom?.
I was thinking 14" or more perhaps.
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Post by Doegirl on Feb 7, 2009 20:42:22 GMT -5
I did not measure the distance, however, that bullseye is 6" across. That gives me a rough estimate of 11-12" drop between the lightest and heaviest arrow.
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Post by BT on Feb 7, 2009 20:53:15 GMT -5
I did not measure the distance, however, that bullseye is 6" across. That gives me a rough estimate of 11-12" drop between the lightest and heaviest arrow. That would be outstanding  I know it's not the perfect weather for this stuff but keep it up and be tough I'd also like to know the impact distance between 15 and 25 yards with the heavy and light shafts and the drop difference between the shafts at 30 yards....when you get the opportunity to do some more shooting  |
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Post by Doegirl on Feb 7, 2009 22:07:58 GMT -5
I did not measure the distance, however, that bullseye is 6" across. That gives me a rough estimate of 11-12" drop between the lightest and heaviest arrow. That would be outstanding I know it's not the perfect weather for this stuff but keep it up and be tough I'd also like to know the impact distance between 15 and 25 yards with the heavy and light shafts and the drop difference between the shafts at 30 yards....when you get the opportunity to do some more shooting I'll do that. I was planning also to get some downrange speeds with my chrono, perhaps up to 40yds. And compare downrange KE and momentum between heavy vs. light shafts. |
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Post by Doegirl on Feb 10, 2009 13:34:45 GMT -5
Today was way too windy for any sort of distance shooting or fine tuning  . So I did some board breaking. Water buffalo ribs are 3/4"+, and those animals are one of Ashby's favorite test subjects. I found some 3/4" veneered particle board laying around. I could not get the broadheads to fully penetrate the board I'm sure it takes quite a bit of pop to drive a 2 3/4" long broadhead completely through a thick board. A shorter chisel tip head probably would have cleared the board. I threw in a weight tube which bumped up the weight to 880grains. All I accomplished was driving the rear of the broadhead into the shaft, splittling both the aluminum and carbon core. A washer might have to be added to protect the shaft in the future. I'm out of commission at the moment, since a mod screw on my bottom cam mysteriously dissappeared. So, for the moment, no buffalo for me |
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Post by BT on Feb 10, 2009 14:29:47 GMT -5
I could not get the broadheads to fully penetrate the board I'm sure it takes quite a bit of pop to drive a 2 3/4" long broadhead completely through a thick board. A shorter chisel tip head probably would have cleared the board. I threw in a weight tube which bumped up the weight to 880grains. All I accomplished was driving the rear of the broadhead into the shaft, splittling both the aluminum and carbon core. A washer might have to be added to protect the shaft in the future. Thats telling me that the Ratio is way off for your set up. Shorter WITH the same ratio, yes.....but that would call for a reduction in the cutting diameter. (which is fine) Shorter alone would effect a steeper angle and therefore would have achieved the same results more or less (literally more or less) Keep in mind... it only got as far as it did because of the profile being so low. The Grizzly heads are cheap (relatively speaking) so why not knock one down to 3/1 as Ashby suggests and give it another go....with a solid backer...that doesn't exceed the shafts diameter. |
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Post by Doegirl on Feb 10, 2009 16:37:08 GMT -5
I could not get the broadheads to fully penetrate the board I'm sure it takes quite a bit of pop to drive a 2 3/4" long broadhead completely through a thick board. A shorter chisel tip head probably would have cleared the board. I threw in a weight tube which bumped up the weight to 880grains. All I accomplished was driving the rear of the broadhead into the shaft, splittling both the aluminum and carbon core. A washer might have to be added to protect the shaft in the future. Thats telling me that the Ratio is way off for your set up. Shorter WITH the same ratio, yes.....but that would call for a reduction in the cutting diameter. (which is fine) Shorter alone would effect a steeper angle and therefore would have achieved the same results more or less (literally more or less) Keep in mind... it only got as far as it did because of the profile being so low. The Grizzly heads are cheap (relatively speaking) so why not knock one down to 3/1 as Ashby suggests and give it another go....with a solid backer...that doesn't exceed the shafts diameter. The broadhead is 2 3/4 X 1 1/16....How would I get that to become a 3:1 ratio head?  I don't think I understand. |
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Post by BT on Feb 10, 2009 18:20:56 GMT -5
Thats telling me that the Ratio is way off for your set up. Shorter WITH the same ratio, yes.....but that would call for a reduction in the cutting diameter. (which is fine) Shorter alone would effect a steeper angle and therefore would have achieved the same results more or less (literally more or less) Keep in mind... it only got as far as it did because of the profile being so low. The Grizzly heads are cheap (relatively speaking) so why not knock one down to 3/1 as Ashby suggests and give it another go....with a solid backer...that doesn't exceed the shafts diameter. The broadhead is 2 3/4 X 1 1/16....How would I get that to become a 3:1 ratio head? I don't think I understand. I'll use the pic that I posted for NYky...  If you do this (I think you should try one) you should not over heat the head while removing that x-tra material  I you use a grinder or dremel, you should hit one side and then the other, scraping away metal a few seconds at a time while moving from one side to the other. This will allow cooling. You might want to just have a small pan of water to dip the head into each time. Whatever you do, it's simple mathematic to determine the ratio. @2 3/4"....I am saying that you removing enough metal to finish the cutting width down to 15/16". That's the equivalent of removing 1/16" off each side....however, by removing this much you are skewing the ratio slightly and to come to a very true 3/1, you may have to end at 7/8"....which is just fine IMO. Before you start freaking out! ;D I have seen lots of animals dropped in short order with a 7/8" head by myself and my then) 8 year old son. For him, it was deer and hogs. For me it was Buffalo, deer, hogs and small game. Never lost one that was hit through the lungs Effective ratio can be manipulated in as much as it's effect on drag by using heads that have a tear drop back which allows the back 3/4 of the blade to actually be higher than the back 1/4. Heads such as this allow good penetration on bone while adding cutting area to soft tissue. Hmmm.... Thats harder to explain than I thought...do you understand what I am trying to say?. Not sure if it really has any importance here but I like to expand on any subject just for the heck of it Oh yeah.... By the way, you dont cut as shows in the picture...that was just an example and the only way to keep it clean was to just draw a straight line. Since the blade is the pic is at an angle, the cut off needed would not be this exaggerated. |
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Post by Doegirl on Feb 10, 2009 22:22:29 GMT -5
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. So I did some board breaking. 
I don't think I understand.