Best way to increase to 10 gpp arrows?

[FrankM]

Sorry about cutting you guys off, I had to rephrase my question. This is the new post.

My gamegetters are good for my 51# bow. I'm worried about these arrows: XT Hunter 5575, 28", 125 gr. field point. 8.02 gpp. wgt. 409 gr. FOC 16.9. Dynamic Spine 88.8. They already have a 15 gr. insert and 20 gr. wgt. behind the point.

I'm wondering what is the best method to get these to 10 gpp on these arrows? Is it always best to add weight up front? Should I consider those weight tubes?

I'd like to compare these to my gamegetters while training for hunting.

[Jason R. Wesbrock]

If your carbons arrows are tuned properly, adding more weight to the front will make them fly weak.

[Ground Hunter]

Frank, you can try weight tubes.  They may affect the spine some.  More weight on the tip WILL change spine and make the shaft weaker.  That's the choice.  Or, you could look into new shafts with a higher spine for the increased weight up front.  Another option, one that I like to get arrow weight up - aluminum shafts.  H

[FrankM]

Yeah, another 100 grains up front will bring them inline with the gamegetters in total weight and dynamic spine. The FOC will be a lot higher on these arrows than the gamegetters though.  I "could" add some weight tubes and lessen the point. This would bring the total weight and FOC close to the gamegetters but at the expense of FOC. Seems like I can get two characteristics close but not all three.

Hmmm, so for training purposes, is FOC or dynamic spine more important when comparing two arrows of similar weight?

[beachbowhunter]

How long are the 5575s and how long is your draw? Unless you don't have any lenght left, I bet you could put in a 100 grain insert and trim 1/4 to 1/2 inch off and they would be ok (subject to bare shafting of course).  I've found that carbons are WAY more sensitive to length than tip weight when it comes to tuning.

[Jason R. Wesbrock]

Frank,

Forget the FOC and tune them for the best flight. Let the FOC be whatever it will be. If when you get them tuned you feel that they are still too light in mass weight, you can always add weight tubes and recheck your tuning. Good arrow flight with normal FOC is a heck of a lot better than fishtailing with high FOC.

Up until a couple years ago, people didn't get wrapped up in FOC (heck, you rarely ever saw the term on a traditional site) and they killed animals just fine.

[FrankM]

So it sounds like I should just add a heavier tip/insert until they make 10 gpp.

[SteveB]

Couple years ago I killed a big cow elk and 4 deer with a 51 to 53# bow and 412gr arrows.
GT 55/75's and 125 grain bh.

[motorhead7963]

Frank" I use the weight tubes and they don't affect my overall spine. I use the GT 55/75s on my bows and I get great flight. It might have been mentioned to try the 35/55 in your bow they weigh the same and will probably tune a little easier for you. give me a call I think I gave you my number we can get together and you can try out some of my arrows. Richard

[SteveB]

Originally posted by FrankM:
So it sounds like I should just add a heavier tip/insert until they make 10 gpp.

No, not if they are tuned to your bow now - at least if arrow flight is more important then what you think an arrow should weigh.

[motorhead7963]

Let me mention one more thing in my GTs I use the brass 100grn inserts on most of my arrows with your length you will be close to 500grns, give or take 20grns.

[FrankM]

To clear up my situation. I have 531 gr. 10 gpp. gamegetter 2018's. I also have these 409 gr. 8 gpp 5575's. I haven't tuned anything yet. But I'd like to try both out on my bow, tune, etc. to see which I like better.

So, should I just shoot them like they are before making changes, or go up to 10 gpp. before I begin?

[JimB]

I believe both your sets of arrows are way too stiff and need more front end weight to tune them.

I need about 270 grs upfront on a 2018 out of a bow that weight.I think when I was shooting 5575's out of that weight bow it took about 300 grs upfront.

You need to tune the arrows first.It will take a specific amount of weight upfront to get the dynamic spine right and however that turns out,that will be your overall weight.There is no way to predict overall weight when you haven't determined what weight point you need(tuning).

I predict that by the time you really tune them,with the proper point weight,you will have more FOC and more than 10 GPP.The 5575's most likely will be over 600 grs.That's not a bad thing.

Once you get the point weight you really need,you won't have to worry about stuffing any weight up the tube.

I would get an assortment of heavier field points,and get tuning.When you are done,you will know what your overall weight is.Don't sweat getting an exact GPP.Having them perfectly tuned is number one.

[FrankM]

I get it. I'm putting the cart before the horse. Shoot for flight first, modify as needed. Tune the 5575's separate from the 2018's.

[FrankM]

Just ordered some test points from 3Rivers Archery. Thanks!

[JimB]

You got it Frank.Let the bow and the arrows tell you what they like.I am still pretty sure that you will have plenty of arrow weight.And don't panic if the arrows end up heavier than you anticipated.More weight will just give you more penetration.If you don't like the trajectory,than you can go to a different shaft to change your overall weight.

Doing some chronograph work with bows that weight,I had to drop arrow weight almost 100 grs to gain 10 fps.It was the same on several bows.It boiled down to :a 6% gain in speed,lost me 15% penetration.100 grs of arrow weight sounds like a lot but the velocity difference isn't nearly what I imagined.dropping arrow weight 95 grs only took me from 155 fps to 165 fps.I tested this over and over.95 grs of arrow weight is almost 2 GPP.I don't even have to think about trajectory difference out to 20 yds.,which is were I like to keep my hunting shots.At 25 yds,there is a slight difference,but not as much as I thought.

Take your time with the tuning and remember,always change one thing at a time.Tune on still days,as a breeze can give you false readings.Don't get in a hurry,just enjoy the time shooting.If it were me,I think I would set one batch of arrows aside until I got one set thoroughly tuned.That will make it simpler and less confusing.Once one is tuned,thst will somewhat point you in the right direction for the other.The 5575's are stiffer,so they will need more point weight and vice versa.Good luck with it.

[Greg Skinner]

I agree with JimB. I'm shooting 55-75s out of a 52# @27" longbow(r/d) and using 100 grain brass inserts and 260 grain points.  Total arrow weight is 650 - 660.  My findings are the same regarding arrow speed, too.