Still messing around with point weight.

[TheBigRedArcher]

Hey all:

I am playing with the point weight on my arrows (grizzly stick sitkas) I am grinding my steel adapters down to reduce the weight. the only thing is that i do not know how little is too little when it comes to the length of the adapter. Does anyone have a relative idea of how much is the minimum for adapter to point/broad head contact? at this point i have about 3/8" or so... can i go a little shorter?

TBRA

Uh-- most people are going up in weight vis a vis FOC-- have you tried other things like a different weight broadhead or BHA? 3/8 isn't much contact. Most importantly, how do your arrows fly? What is the weight of your bow and the weight you are aiming for with your arrows?

[TheBigRedArcher]

All but one arrow fly well. I an going on a statement from the the guys at alaska bowhunting. This is just a try it and see thing for me. The guy I spoke to said there is a bell curve on the grizzly sticks being that they are full tapered and that i might be able to go a little lighter from my total of the brass 75gr. insert, steel adapter 125gr., and 145gr. point/broadhead and gain a little speed. for the record here I am all about KE, I don't care much about speed but it does add into the equation for maximum penetration.

TBRA

[JimB]

You might be OK with 3/8",but I wouldn't go shorter.Personally,I would go to a lighter adapter before grinding that much length.I would rather have a full length aluminum adapter than a steel one that short.

What does the adapter weigh now,after being ground down?

[cacciatore]

I would rather shorten the arrow if this is possible and add weight on the point!If you can't do that use the aluminum adapter and/or lighter points.

[Stumpkiller]

I get by with 1/2" clearance beyond my riser.  It will depend on your finger thickness (don't forget gloves), grip style, rest thickness and the riser itself.

I also shoot double-edged broadheads aligned flat.

I have some blunts I pull inside the riser (left-overs from my longbow days).  Works great as long as you don't get hyped up and overdraw.

[gvdocholiday]

Originally posted by JimB:
You might be OK with 3/8",but I wouldn't go shorter.Personally,I would go to a lighter adapter before grinding that much length.I would rather have a full length aluminum adapter than a steel one that short.

Exactly.  The more contact the better.

[Ragnarok Forge]

Big Red Archer,

I have to say here the KE has nothing to do with penetration.  It is a measure of stored energy in the arrow in flight.  Impulse Momentum is the equation you want for measuring penetration upon impact with any particular medium.  Read over the Ashby reports with a focus on the penetration parts.  He covers the impulse momentum equation fully.  

KE uses velocity squared as part of the equation which provides a high KE number.  Mass is the ruling component of the momentum equation and is what determines penetration levels upon impact with any medium.  Compound companies trumpet KE as the ruling numbers since speed sells bows.

I would reverse path and look at running the full weight insert or adapter and find a head weight that tunes right for your bow.

[TheBigRedArcher]

What would be nice is if they made an aluminum adapter in addition to the brass ones that come with the arrows. I think that would give me more of a window to play with. I am going to go to the range tonight and see what happens. i will keep ya'll posted.

[awbowman]

Like someone said, go with a lighter adapter.  I think they sell little 5 grain washers that could allow you to "dial" in the spine you want.

[amicus]

I think you can buy 100 gr steel inserts.

Gilbert

[Bowmania]

Steel adaptors come in aluminum which are about 35 - 40 grains, and steel adapters that come in 75,100,125 grains.

[TheBigRedArcher]

Well, as I said. I went to the range last night and while the arrows flew like... lets say less than perfect when bare shafted, They flew great with 25gr aluminum adapters and 145gr points, with glue and all included the points weigh in at between 107-173 grains. making a total arrow weight of 590ish grains looks like all the grinding I did was for not.

Now the next problem is broad head flight.

TBRA

[Beanbag]

Big Red Archer, You probably know this but the spine on the Alaska shafts leave a little to be disired.I like the shafts and do use them but find that they are very inconsistant in spine. Once you get them sorted out I think they are pretty nice. I have spined them as per their instructions online and seem to get a couple that are always off a bit.I use their brass insert adapters to adjust weight and like them alot because you can fine tune with 10gr and 50gr inserts. Might give you a little room to work.  I'm not sure if they have an insert for adding weight to the nock end. I did that with Gold tips , it acts to stiffen your spine which sounds like it might be the problem. just a thought Jim G

[TheBigRedArcher]

Bean:

The 10gr and 50gr tunning weights wont work for me unless I take the brass insert out, i put the aluminum knock adapters in the back end and use the Arizona z-knocks. I do however agree with you about the spine inconsistencies.  Apparently they also just changed the way the shaft is constructed ( as per some guy I spoke to at Alaska Bow hunting) which took away or at least reduced the difference in spine from axis to axis like a wood arrow has because of the grain in the wood. I got them flying and at about 20yards I'm in 6" but I need a lot more practice, i just don't get to shoot as much as I would like.

TBRA

[Jeff Mundy]

wouldn't it make more sense to go with another pt. weight/ adapter combo? just sayin...