new Equinox owner and FOC question

tworr · Post by **tworr** » Thu Sep 20, 2007 3:28 pm

I wanted to introduce myself and get my very first Excalibur forum question posted.

I just bought a Equinox and boy am I loving it!! What a great crossbow. Thank you Excalibur for such a solid performing product.

This is my first crossbow, so my goal this year is to enjoy the full season by only using the Equinox. Wish me luck!!

Now for my question...

I've already had to break down and buy a EZ fletcher due to putting my bolts in my targets up to their nocks which seems to a common problem around here. What a great problem to have right?

Searching the forum here I've been able to learn a lot, but I still have an elementary question that I need answered on arrow building.

When figuring FOC, is total length figured from the nock to tip or just the shaft(including inserts) length? I'm sure it doesn't matter to most of you, but if I use "to the tip" then I get what looks to be a low FOC.

Lenght to Tip - FOC

Firebolts 5" stock fletching - BH 6.3% Field Tip 7.4%
Unknown 2" fletching - BH 7.3% Field Tip 7.9%
Firebolt 2" Blazer fletching - BH 8.6% Field Tip 9.8%

Length of Shaft - FOC

Firebolts 5" stock fletching - BH 10.8% Field Tip 9.6%
Unknown 2" fletching - BH 11.7% Field Tip 10.4%
Firebolt 2" Blazer fletching - BH 13.3% Field Tip 12.1%

One thing I want to add is that these are my first fletchings and while I think I did pretty good, I'm sure there is room for improvement.

I am using the older (black) 4 degree offset EZ fletcher and I didn't add anything to the back of the bolt to get the fletching closer to the back of the shaft. Right now they are 1.25" from the back. I figured this would be OK since the 5" fletching was 1.125" on the Firebolts.

Thanks for listening,

Tworr from Arkansas

Matthias72 · Post by **Matthias72** » Thu Sep 20, 2007 3:52 pm

First of all congratulations for your crossbow and wellcome on this forum.
Someone calcules the FOC considering the lenght of the arrow without point; some otherone uses the complite arrow lenght including the point. Personally I use the average lenght.
However, indipendently the sistem you use, the FOC importance depends principally on your shooting distance. If you shoot at 10 yards the difference between a fantastic 20% FOC arrow and one bad 8% FOC arrow is only some millimeters. But If you shoot at long distance >50yards the difference becames centimeters, especially if you use broadheads or in windy days or if you move your crossbow during the shoot. So If I could suggest you, try to put the major mass as possible on the front of the arrow and the less as possible on the tail...done that, sleep quite and good shooting and hunting!

Best regards

Matthias

Normous · Post by **Normous** » Thu Sep 20, 2007 4:24 pm

My Equinox has a preference for the Blazer/ carbon bolt. To increase FOC, I removed the rear insert and cut some 60% from it, then drilled the insert threads out to additionally lighten the rear= a 12 gr. loss. Up front one could add and glue a brass add on or a 8/32 1/4" screw to increase front weight, about 20 grains or so (if you are using 100 gr. tips). My combo weighs 360 gr in a GT II and flight characteristics are great in our Vortex and Equinox. You could cut a piece of pencil 3/8"-3/4" and drop it into your AE fletcher to move the vanes back some.
Welcome to the forum and good luck.

Norm

diesel · Post by **diesel** » Thu Sep 20, 2007 8:15 pm

First welcome to the forum and I'm sure you will enjoy the new bow.
bstout: that looks like a great link. I've not seen that one.

I like to use the one on Gold Tips web site that way I can see what I have before I put the bolt together. It's under products.
I agree with bstout I like a 15% FOC too.

tworr · Post by **tworr** » Fri Sep 21, 2007 9:43 am

I want to thank everyone for the warm welcome and the great advice.

Matthias72 - I will try to move up to a heavier BH. What is the best weight of BH that you have found?

Is there a general rule for how much speed is loss per weight increase of an arrow/BH? That seems like useful information that new users would ask for. I'm sighted in at 320fps and that seems to be the average speed based on my reading on this site for the Eqnox with stock string and arrow. I know there are several variables, but a general "what to expect" figures might be helpful.

Enomous - That some great advice on cutting the weight on the tail. I will give that a try as well!!

Bstout- Thanks for the link, I believe I actually followed another post of yours that had a link for that calculator when I figure my FOC.

Diesel - I will give you site another try. I don't have a scale yet so I wasn't able to take advantage of the component sites.

Here is another one that I found.
http://www.archery-engineering.co.za/co ... ulator.htm

Here is another version of the jackson archery calculator based on components.
http://home.att.net/%7Esajackson/foc.html

Tworr

Matthias72 · Post by **Matthias72** » Fri Sep 21, 2007 1:42 pm

I didn't understand what means BH for you. However +-5 granis on the arrow, means +-1fps of speed that is not the exact reality but to have an idea it is good.

Best regards

Matthias

tworr · Post by **tworr** » Fri Sep 21, 2007 1:45 pm

Sorry,

BH=Broad Head
FP would be Field Point

Thank you for the information. That's exactly what I was looking for!

Tworr