Would someone check my work?

[Cottonmouth]

I've a Martin Jaguar (45# at 28") on the way, and would like to get some arrows.  Been playing with Stu Miller's Dynamic spine calculator, and here's what I've come up with:

3Rivers TradOnly 300 cut to 31.25"
Grizzly 200 gr
Brass Broadhead Adapters 100gr

This should give me a TW of 625 gr with an FOC of 23.3%.

Would someone check my work?  I would've paid more attention in Algebra if I'd known I'd need it to help pick my arrows  

[Jerry Wald]

Just do a search for the calculator by Rob d and punch in the numbers bud,

jer Bear

[**DONOTDELETE**]

what nocks will you be using?

[JRY309]

I don't know but a 300 spine arrow is pretty stiff for a 45# bow and thats a heavy arrow.Your trajectory must be like an arc,what is your draw length?

[ishoot4thrills]

Make sure you entered the correct center shot calculation. Also, allow for material added to the strike plate when estimating center shot.

Center shot entries are probably the most important entries when using Stu's calculator to determine correct spine. Makes a HUGE difference.

[**DONOTDELETE**]

some questions first

I checked 3Rivers and didn't see a grizzly 220grn, How did you get 220 grn's?

You say 100grn adapter, did you mean insert?

You didn't say how many/size for fletching?

what is your draw length?


What I got with just Your info is
bow = recurve\\50\\28\\28\\-1/16th\\b-50  56.8
arrow = trad 300\\31.5\\220\\100\\no\\11(signature nock)\\4"feather   48.2


Arrow Outputs            
Total Weight (656)   Specific Weight (14.0)   F.O.C. (23.1%)   Speed (154.4)   Energy (34.7)

Now to get the right numbers answer the questions I asked or You'll get the wrong numbers and You'll not get good arrow flight.


Example of the right numbers, My bow & arrows

bow
recurve\\50\\28\\27.5\\-1/8th\\b-50 = 65.4
arrow
2117\\28.5\\202[42grn adapter-160grn point]\\26grn[insert]\\no\\11grn[nock]\\4"[feathers] = 63.0

            
Arrow Outputs            
Total Weight (587)   Specific Weight (11.6)   F.O.C. (18%)   Speed (167.7)   Energy (36.6)

[WESTBROOK]

Sal, he said 200 grizzly

They make a 100g brass glue-on BH adapter that goes in the shaft, it is the insert.

I'm no carbon guru, but a 300 is way stiff (like #100). I could see that hardware on a 400.

Eric

[**DONOTDELETE**]

My Bad... sorry.

[Cottonmouth]

I really appreciate all the replies.

Ishoot, I believe the Jaguar is center shot.

My draw length is 28".  

I want a heavy arrow and EFOC.  

3Rivers description of the TradOnly 340's is 3 5" LW.

I've plugged the numbers into Stu's calculator to get a good starting point, but I may have plugged in the wrong numbers if everyone thinks the 340's are way too stiff  :(

[xtrema312]

They thought the 300 was way stiff.  340 is better, but I would think a little too stiff still and you don't have a lot of room for working longer and cutting down to tune.

Is that bow center shot or center cut?

If your bow with side plate is right on center then that arrow could work fine, but I would start full lenght and work down.

[koger]

A buddy of mine has the same bow, we set it up qith GT35/55, 150 WW, 4" parabolic feathers and cut to 29". Flys great and killed deer like no tomorow. May not be the weight you are wanting, but sure shoots great.

[**DONOTDELETE**]

I would try the 50grn brass inserts, 75grn steel BH adaptor with the 200grn grizzly. cut arrows to 29.5"BOP trad 300's 59.8


 Arrow Outputs            
Total Weight (641)   Specific Weight (13.7)   F.O.C. (24.1)   Speed (156.0)   Energy (34.6)

[JimB]

I have a couple bows that are 45# at my 29" drawlength and both are cut to center.I set up some 55/75(400 spine) Gold Tip Trads for them that are 30" long,5" 3 fletch,cap wrap and app. 260grs up front,including point,adapter,insert and aluminum footing.FOC is almost 21%.Total weight is 568 grs.

In my experience,if I wanted to jump to the next carbon spine group,on the same bow,I would have to add at least 120 grs more point weight to bring the dynamic spine down.

I have some 30" 340 spine arrows made up for a 55# bow and they required 405 grs up front to shoot off this bow.FOC is 28% and total weight is 709 grs.

I think if you try to shoot 340 spine arrows off that bow,you will end up with at least a 750 gr arrow by the time you get enough point weight on it.

I would try 400 spine if you want some FOC and probably experiment with aluminum adaptors first.Experiment with different point weights to get them to shoot.My 400's for the 45# bow have a 160 gr broadhead,75 gr adaptor and 14 gr aluminum adaptor plus 10-11 gr footing.

You would want an assortment of 200 gr+ screw in field points if you use the aluminum adapters.

Cutting your arrows shorter than my 30" ones would allow you a little more point weight and would up your overall weight and FOC a little

If you want more FOC,don't use the wood grain shafts.The lighter,black shafts help with that.

[bshunter]

GT 35/55 or Carbon Express 150, I shoot 48'ish on most of my bows, I wouldn't go any stiffer than a .500 spine, even with a center shot bow. It is not hard to get a 550 grain arrow with the CX Hertiage, /stu's calc always says that my arrow is too weak, but when I bare shaft, always a little stiff, but you have a lot of room to play, but honestly I don't know if you would be happy with that set-up, unless you were shooting  a max of 15 yds. Lastly, do a search on bare shafting or arrow tuning and you will get pages of great info here. good luck and good shootin.

[Cottonmouth]

Thanks for all the info folks, I got to go study some more before I plunk down an $$$ for arrows...

[ishoot4thrills]

Remember, if a bow is cut to center, it won't still be acting like it is after you add material to the strike plate area. You must allow for that added material thickness when you enter the data into the calculator.

[Kenneth]

I honestly think you're gonna need a 500 spine carbon cut to 29" or 30" to get good flight out of that set-up.  You may get a 400 spine to work though.  Order the test kit from 3rivers, it is money very well spent.

[**DONOTDELETE**]

This will really help, Get one of their test kits. You can get the kit that has 1 shaft of each size/spine and find which one flies the best.

[30coupe]

Here is the setup I use for my 46# Kanati. It blows right through whitetails. BTW I used a Zwickey Delta broadhead on a 100 grain adapter. The shaft is a Beman ICS Bowhunter with the standard insert and 3-5" feathers. This weight is plenty heavy for a 45-46# bow to get decent arrow flight along with great penetration. I think you will find anything stiffer than .500 spine to be too stiff for your bow at your draw length. I draw the same 28" as you. Good luck.

ARROW   length   30
shaft+feathers+nock wt      245
separate insert weight?      30
adapter weight?      100
point weight      135
total arrow weight      510
balance length      22.38
   FOC %   24.60
      
draw wt   arrow wt   GPP
46   510   11.09

[legends1]

Just my 2 cents,but I think you would be happier with a arrow of around 500grns. or just over out of your 45# bow it would work very well for hogs and deer.Again,just my 2 cents