We sent a Covert hunter to an Archer in the USA. here was his take so far

g1225b

New member
That's really impressive. Very quiet, the speed' my goodness 10fps faster than HEX6's! I could tell they did not want to put the bow down, even in the subzero temps. They also did not look like they were pulling 55lbs. You folks at Borders are to be congradualated. That's one fine bow. Have you figured out if the HEX7 can be used on any ILF or formula target risers, or is the geometry wrong?
 

BorderBows

New member
That's really impressive. Very quiet, the speed' my goodness 10fps faster than HEX6's! I could tell they did not want to put the bow down, even in the subzero temps. They also did not look like they were pulling 55lbs. You folks at Borders are to be congradualated. That's one fine bow. Have you figured out if the HEX7 can be used on any ILF or formula target risers, or is the geometry wrong?
ah... let me see if i can explain some of our thinking.

these low BHs give us all sorts of issues designing the bow for short risers.

if you look at the vid, at 6.5" BH and tall fletch off the shelf, they were not using arm guards.

so 6.5" of clearance should be fine!

we can set the limbs are up for long risers. but ILF being ILF means it also needs to fit shorter risers.
this isnt going to work with low deflex risers.
but we can see ILF working well with the longer riser.

have a look at the where the string lifts off the limb at brace, you can see it lifts where the radii changes on the limb...
to get this location you need to get the preload right, miss this and the limbs loose the design remit.

This tighter radii is part key the design.
if we cant get this to work on ILF then we have issues...
if we can get it to happen, then its a case of looking at the repercussions for the short riser comunity.

short risers means lower BH, and if we are getting 25" risers to settle out at 6.5" then the short risers will be closer to 5.5" and thats not going to happen.
so the higher BH on the shorter riser will mean a string lift point thats all wrong for the covert hunter...
 

g1225b

New member
ah... let me see if i can explain some of our thinking.

these low BHs give us all sorts of issues designing the bow for short risers.

if you look at the vid, at 6.5" BH and tall fletch off the shelf, they were not using arm guards.

so 6.5" of clearance should be fine!

we can set the limbs are up for long risers. but ILF being ILF means it also needs to fit shorter risers.
this isnt going to work with low deflex risers.
but we can see ILF working well with the longer riser.

have a look at the where the string lifts off the limb at brace, you can see it lifts where the radii changes on the limb...
to get this location you need to get the preload right, miss this and the limbs loose the design remit.

This tighter radii is part key the design.
if we cant get this to work on ILF then we have issues...
if we can get it to happen, then its a case of looking at the repercussions for the short riser comunity.

short risers means lower BH, and if we are getting 25" risers to settle out at 6.5" then the short risers will be closer to 5.5" and thats not going to happen.
so the higher BH on the shorter riser will mean a string lift point thats all wrong for the covert hunter...


I take it that a set of long HEX7's would work just fine on a 27" formula riser. Approx. how much lower would the brace be from the HEX6. I'm currently using 7.5 on a 72" bow. Excuse me if I'm drooling a little.
 

BorderBows

New member
I take it that a set of long HEX7's would work just fine on a 27" formula riser. Approx. how much lower would the brace be from the HEX6. I'm currently using 7.5 on a 72" bow. Excuse me if I'm drooling a little.
our thoughts are 6.5" is about best. it works best with longbows and flatbows due to the compromise in power stroke and not hitting the back of your hand. so that would be our ideal... the longer limbs will probably be a bit higher. as to allow room for the shorter lengths.
dont know yet... need to see what the formers give us. this part is the difference between theory and actuallity

the longer the riser the better chance of it working.
 

g1225b

New member
Sid, another interesting thing the arrow spine seems to be quite heavy (75-95#)and on a carbon shaft. Any idea what the actual spine number is for those GT carbon shafts? A 200 grain tip softens the spine a little. Ray stated the shafts he was shooting outside were slightly stiffer but bareshafted straight. It would seem the extra horsepower of the HEX7 requires a substantially stiffer spine. Have you folks seen much difference from spines required for the HEX6 as you've tested the prototype HEX7 around the shop there?
 

BorderBows

New member
the problem seems to be it shoots alot of arrow setups with convincing credability... we tried a range of shafts and point weights at up to 35 yards and the differences were subtle. the big difference was the drop at distance due to mass difference. we gave the bow to a well respected longbow shot here. for a 10min play. even he said the same. you could hardly tell what was what other than the drop. all seems to come out with good manners.
if that makes any sense...

i do love the lack of arm guards. in the 3rd vid though
 

g1225b

New member
The amount of string wrap on the limb tips is huge, looks like at least 8". That means you're shortening the string by 16" as the limbs close which has to have a large effect on damping down string oscillation amplitude which could explain the large spine tolerance. The HEX6's run about 6" of wrap per limb and are fairly spine tolerant.I can shoot from a 450 to a 490 to a 530 spine and see very little difference in groups at 60yds with my HEX6's. Choosing which is best takes a LOT of shooting. Have you taken any slo mo videos to get an idea if arrow clearance is any different from the HEX6?
 

BorderBows

New member
The amount of string wrap on the limb tips is huge, looks like at least 8". That means you're shortening the string by 16" as the limbs close which has to have a large effect on damping down string oscillation amplitude which could explain the large spine tolerance. The HEX6's run about 6" of wrap per limb and are fairly spine tolerant.I can shoot from a 450 to a 490 to a 530 spine and see very little difference in groups at 60yds with my HEX6's. Choosing which is best takes a LOT of shooting. Have you taken any slo mo videos to get an idea if arrow clearance is any different from the HEX6?
it does take a lot of shooting...
Most people don't understand this I think.

they go by the Easton chart, as per poundage, but discount the extra stored energy.

this bow will certainly show this to be true or false.

yes the string wrap is significantly more than a hex6.


I think Matt Potter (another long draw fella with a 27" riser) has also noticed this. though hes barebow. Maybe he will pop up and tell us his experience...
 

BorderBows

New member
this is one of the reasons I disagree in part with a limb review done not that long ago. although the test was not bad, it didn't in our view give the different design a proper outing.
That said the scores were not poor, they were on par with very top end traditional Target limbs. the disheartening thing was the coments were random fliers. which to me meant a little contact with the riser. but the review gave the na-sayers some leverage to say the conventional profiles were best.
to which the CXG came out with some very very good scores on the test.

Id say that is because the bow feels normal to the tester, and that the spine was easier to find due to it being in the zone of experience of that archer.

as you point out. ALOT of shooting to decern the best shaft, and that is when you get best forgiveness IMHO
 

darthTer

Active member
Supporter
Ironman
American Shoot
ALOT of shooting to decern the best shaft, and that is when you get best forgiveness IMHO
Surely there must be a more accurate way to identify spine??? The Easton spine chart has been around forever, with only the odd tweak every now & again. Limb & riser technology is changing, designs are changing, yet the easton chart remains the same.
 
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