arrow weight

[backyard]

have been looking online to find out what would be the min for arrow .... so far 5 gpi is what I found, is there a +/- to this ... I have some fatboys that are weighting in at 340 and my 70 lbs would make this to be 4.8571 gpi ... is this close enough if not I have heard that you can weight them but with what? thanks for your time

[L.O.S.T.Arrow]

Many bow manufacturers will VOID warranty with arrows under 5 GPI..

Reason being...using an 5 GPI is essentially resembling a dry-fire bow...like a mini dryfire each time you shoot...visible signs are usually cracked limbs..cupped cams...etc

it is very hard on the bow...some worst than others...some have no issues..

Arrows that light ..other than the dry fire factor...are usually under spined for harder tuning...makes bow noisy and is hard on rest and bow itself...some would even consider your set up dangerous...

heavier arrows usually make bow easier to tune...are much more quite and are safer to use with no damage to bow..better penetration etc...

Personally would suggest a 400 grain arrow at lightest with your set-up

Neil

[RoscoeP]

Provided your spine is correct just add a heavier point.

[normanrd]

Or turn your bow down to 68 and your good to go too.

[backyard]

the arrows are 400 fatboys that i'm talking about..... the tips are glued in what would be the easiest way to get them out and put heavier ones in...

[normanrd]

Depending on what they were glued in with sometimes you can gently heat them and pull them out. This is kind of low percentage. Better to cut them off and glue a heavier one in with a fresh start. If you turn your bow down to 68 you will get the same performance as if the bow was at 70 and the arrow was 10 grains heavier. Might save some time and money.

[backyard]

will not be able to cut off wont be long enough... I guess I will just turn down the weight

[HoytAlpha35]

Unless those Fatboys are ultra short 25" and an 80 grain point you are very likely underspined. Possibly to the point that the arrows will break while being shot. To keep shooting 70lbs a 340's or maybe 300's will be needed. I dont follow the current arrow charts as they don't account for the high performance bows and dynamic spine. Eg. a bow with an ibo of 350 fps will need a stiffer arrow than a bow with an ibo of 320 even if the draw weight, length are the same and arrow charts dont account for this. Also, another scenario that ties in with dynamic spine is arrow weight, if you go with a lighter arrow a stiffer spine is need as there isn't as much arrow weight to absorb the energy of the shot and that plays into how much the arrow will flex.

What bow, draw length, arrow length? I've got a couple of the arrow programs and can give some recommendations if you like.

[backyard]

Rpm360, 28 1/2 draw, 70 lbs, 28"-29" length arrow

[WildOrchid]

Originally Posted by rpm360

will not be able to cut off wont be long enough... I guess I will just turn down the weight

We use to clamp the arrow carefully and heat the point, making sure not to get the arrow shaft. As the point heat's up, the glue soften's and with a pair of pliers you can pull the point out.

[HoytAlpha35]

Even at a 340 spine, 60 lb draw you'd be underspined. Always better to go with a heavier spine as they will be dynamically more consistent.

[HoytAlpha35]

Here is another example.

Goldtip Ultralight 22, .300 Spine

[HoytAlpha35]

As you can see the performance of the bow has a huge effect. What's your hunting arrow? Do you run a fixed blade? Have you had trouble tuning a fixed blade?

[backyard]

blue streak select is my hunting arrow 350.. no fixed blade.

[HoytAlpha35]

Definitely on the weak side with those. Next time you buy arrows I would highly recommend going to a .300 spine

[gpelker]

Originally Posted by HoytAlpha35

Even at a 340 spine, 60 lb draw you'd be underspined. Always better to go with a heavier spine as they will be dynamically more consistent.

what program or website is that?

[backyard]

Originally Posted by HoytAlpha35

Definitely on the weak side with those. Next time you buy arrows I would highly recommend going to a .300 spine

not sure what chart you are going off of, I pick it off Carbon Express wed site... I do admit thought the fatboys should have been 340 spine but have to do it next time...

[L.O.S.T.Arrow]

Originally Posted by rpm360

not sure what chart you are going off of, I pick it off Carbon Express wed site... I do admit thought the fatboys should have been 340 spine but have to do it next time...

On the CX Blue Streaks...with 70 lb high energy cam the .350's are on low/border line side of scale but still shootable and well within the 5GPI min...However for hunting the CX .300's will give you that weight, penertration and easier tuning arrow without adding a lot of weight...

Neil

[backyard]

thank you everyone for your input