Question on arrow weight.

Swiftspeed10 · April 18, 2013, 12:02:00 AM

So I have always shot 50# bows and used carbon arrows-400 cut to 29 inches. I have recently started using a 57# bow and I am wondering if the arrows are heavy enough to use. I know you are supposed to use around 10 grains per pound so if my arrow is 400 cut to 29 inches (originally 32) how many grains would that leave me to work with?

Echatham · April 18, 2013, 12:40:00 AM

the shafts should have a gpi number.... probably roughly 8 or 9 grains per inch. add your point weight.... probably 100 or 125... and about 15 gr or so for tje nock... little more for the feathers..... insert is probably 30 gr or so. need more info. the 400 number has nothing to do with weight.... its a spine rating

JimB · April 18, 2013, 12:57:00 AM

I'd be first concerned with what tunes to the bow.If you use the identical .400 shafts,you may have to drop 50 grs of point weight from what you use on the 50# bow.You might be able to find a heavier weight .400 shaft to gain overall weight.

Swiftspeed10 · April 18, 2013, 01:03:00 AM

I use this they are 8.4 grains per inch.

Link to 3Rivers listing of arrows

so 8.4x29 inches=243.6
+125 for the point
+30 for insert
+15 for nock
total weight=413.

So they are far too light to shoot from a #57 bow. What can I do?

April 18, 2013, 01:07:00 AM

The arrow you listed above will only be 7.24gpp off a 57# draw weight. That is pretty light. If it was me, and hunting was my intended purpose, I would strive to find a way to end up with a heavier arrow.

If your arrow was properly tuned to your 50# bow, it more than likey will not be tuned well for your 57# bow without making some changes.

The 10gpp is not a steadfast rule. Lots of guys hunt with less and lots with more. Proper tuning is the most important thing.

Bisch

Swiftspeed10 · April 18, 2013, 01:12:00 AM

should I try 250 grain points or is it too much weight in the front?

Thinking about buying this and seeing if any of the points fly well out of my bow.

http://www.3riversarchery.com/Screw-in+5%2F16+Heavy+Weight+Field+Point+Test+Kit_iCF516-T_baseitem.html

Orion · April 18, 2013, 10:51:00 AM

Adding weight will just make the arrow weaker, and you need a stiffer arrow. If those arrows were tuned to your 50# bow, the spine will be too light for your heavier bow, particularly a quick one like a Centaur. Think it might be time for some heavier spined shafts. A shaft test kit (not point test kit) is a good place to start. Good luck.

JimB · April 18, 2013, 11:30:00 AM

It's a fact.If your arrows shoot well now,off your 50# bow they won't shoot well at all from 57#.Adding point weight will make it worse.

Like I said,you need different shafts.There's no way around it.Even internal weights won't help because you still need less point weight and I doubt if there is a broadhead light enough.

Swiftspeed10 · April 18, 2013, 11:34:00 AM

thanks guys, going to order a spine test kit.

Shawn Leonard · April 18, 2013, 04:06:00 PM

Sorry but disagree, you never give your draw length other than what it says under your name. If you in fact draw 28"s and are shooting a 50# PSE Impala, you must have a ton of weight on that 400, cause that will be way to stiff out of that bow unless you have 325 grains or more of point weight on that bow. Their is no reason that Centaur at 57#s should not shoot a .400 spined arrow and even at that I bet you would need at least 275 up front on that .400 spine arrow for good flight. I know I owned 3 Centaurs and the only one I shot .400 spine out of was 63#s at my 28.5" draw and I shot 240 grains up front out of that one. Shawn

CRS · April 18, 2013, 06:50:00 PM

Shoot them and see, but I think you will have to go to a 340 shaft.

I would not be afraid to leave them longer if that is what is needed to tune. Then you have the advantage of cutting them down if you want to add more weight.

I have completely quit worrying about arrow length and go with arrow flight and weight. I prefer 10-11gr per lb.

Swiftspeed10 · April 18, 2013, 06:50:00 PM

I draw closer to 27 but the 400s always flew well with 175s out of my.pse

CRS · April 18, 2013, 07:06:00 PM

When you say flew well, did you bareshaft them? I have seen that once in the ballpark, most fletched arrows shoot good to the naked eye, but when bareshafting at 20 yards they are off.

Since you are only drawing 29, you could cut the shafts down to shoot out of the 57# and then change tips to get them to shoot out of your 50#.

The amount of centershot difference between the bows is another huger factor.

SS Snuffer · April 18, 2013, 07:19:00 PM

Shawns is right. Your arrows are way to stiff for the bow you have been shooting them out of. Try bare shafting them and you will see. Your 400's should shoot better out of the 57lb. bow but could still be to stiff.

CRS · April 18, 2013, 09:17:00 PM

I shoot 400's out of all my 50# bows and move up to 340's when get into the upper 50's and low 60's.

But centershot makes a huge difference. There is a difference between skinny carbons ie MFX, Axis, versus fatter shafts like goldtip and victory. The skinnier shafts create a more centershot setup.

If your PSE and Centaur are centershot or close to it, you may be able to use the same shaft. If the Centaur is not, you may still be able to shoot the same arrow as you will need a softer shaft.

Only way to find out is bareshaft them. I know that process has enlightened me. But I have a cut off saw and the full range of tips to play with.