the making of a heavier hunting arrow

[olddogrib]

Let me start out with the staus quo.  I shoot .500 spine carbons cut to 29-1/4" BOP with  standard aluminum inserts and 175 gr. heads.  They fly great and I know they're fine for whitetails.  I've toyed with the notion of a heavier hunting arrow with a bit more FOC.  I thought I might be able to go to a full length .400 and put a ton of weight up front, but that hasn't worked out. My only other option appears to be heavy inserts on the .500's.  I know others will disagree, but from my experience the combined weight of heavy inserts plus head will definitely not spine the same as identical weight in the head itself.  It seems the internal length of a 100 gr. brass insert produces a stiffening effect, similar to footing. Anybody got an idea as to whether I could cut my shafts and get the heavy insert to work with the right head? I may have 3/4" to work with, but I don't won't to put myself in a situation where I'm back to 125 gr. or less head weight options, there simply aren't enough broadhead choices, so I'd like to keep head weight at 150 gr. or more.  I've tried the 100 gr. inserts on my existing arrows, but they didn't spine satisfactorily, so it does have an effect.  I think this might work, anybody have any idea how much I'd have to cut to accommodate the inserts and a heavy head?  I don't want to mess up a good arrow if this is an exercise in futility.

[ChuckC]

Have you tried weight tubes ?  Doesn't help with the FOC, but if you are getting good flight now, why change it?  I use them in a similar set up because .500s are just too light ( for me) and my bow makes more noise, until I add about 90 grains of tubing.
ChuckC

I can't tell you how much you have to cut off to get it to work, but i can tell you that you are right in assuming that if you add the 100gr insert where the 15-20gr insert was, without changing anything else, it will definitely mess up your tune.

The best way I would suggest would be to give up one of your arrows, put the 100gr insert in, and tune however you tune to figure out what to do. Then start cutting till you either get it right, or get too short and figure out that it won't work with those shafts.

Bisch

[Jake Scott]

It's been my experience that changes in point weight don't effect spine nearly as much as shortening or lengthening the arrow.  You don't say your poundage, or how much weight you want to gain on your arrows.  Both would be useful to know.

Brass inserts do change spine drastically in some cases, in my experience, especially HIT.  3/4 of an inch can make a huge difference in spine, I wouldn't be afraid to try it, if it were me.  

Good luck,

Jake

[Bladepeek]

If you are already perfectly tuned with .500 spine and 29 1/4" arrows, you will have to go to a stiffer spine and a LOT heavier head to keep that length. You said the 400 spine arrow with "a ton" of weight up front didn't work out. That's not too descriptive of the results.

I do know that when I was trying to build an extreme, ultra FOC heavy arrow for my 46# bow, I was able to build some with GT 5575 and 7595 "with a ton of weight up front" that flew perfectly - both bare shaft and fletched. I did need to leave them, especially the 7595, longer than my 1535 and 3555 arrows that were tuned to the bow. And I did wind up with slightly over 400 gr up front on the full length 7595 before it started flying true. Let me tell you, you could hear that one hit!

[olddogrib]

I'm shooting 48# OTF with a 28.5" draw, 3U. I'm not hung up on any specific total weight or FOC gain.  Obviously, any combination that can utilize the 100 grain inserts will get a net gain, as I don't think you can even get 75 gr. point outside of kids arrows.  With the constraint of broadhead choices that I mentioned being a consideration, if I went with the minimum of 150 gr. we're talking increasing  combined insert/broadhead weight 250-400 gr. The reason I wasn't more specific than "a ton" is that I've tried every conceivable configuration of .400's full length and cut to the same 29-1/4", with standard inserts and the 100 gr. brass, and point weight from 100-300 grains.  Ironically, the best flight was from the full length, standard inserts, and the same 175.gr. heads. This may be my answer, but I wouldn't change purely for the negligible weight gain of GPI of the stiffer shafts as they still don't fly as well as my .500's. Another factor I probably should have mentioned is that I've gone to a 3/4" fixed crawl and shoot the same shafts as when I shot touching the nock. I was expecting to have to make big time changes but they actually bare shaft slightly better, which could mean I was borderline too weak before as the crawl is effectively shortening my power stroke by 1/2" or so.  If I was wanting arrow weight only I'd simply go to GT .500 Heavy Hunters.  Nothing's broke, so maybe I just shouldn't try to fix it.

[Orion]

It seems you can increase front end weight without cutting the shaft(s), though that's still an option.  Can mess around with 50-75 and 100 grain inserts and 75-100 and 125 grain steel adaptors, and an infinite number of point weights to try lots of different front end combinations.

In theory, the longer insert does stiffen the arrow a bit vis-a-vis more weight in the broad head/adaptor, but usually not enough to make a practical difference. At least that's been my experience.

[Burnsie]

Arrow Dynamics - black shafts, 29-5/8", standard inserts and 250grn up front from a 50# Whip shoot great.