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m00se
10-05-2010, 06:17 AM
I want to get carbon arrows for my bow... a 1991 or 1992 vintage... umm... hybrid. If I remember correctly, it is a Cougar riser with Prowler limbs and Megacams. The draw length is 30", draw weight is 66lbs, holding weight is 65%.

What is the minimum arrow weight for this bow?

Can I adjust the letoff?

It is supposed to go to 70lbs, but the most I can now get is 66. Would replacing the cables help? Is there anything else I can do to restore the draw weight? Or is it just "old and tired"?

KStigall
10-05-2010, 06:44 AM
I want to get carbon arrows for my bow... a 1991 or 1992 vintage... umm... hybrid. If I remember correctly, it is a Cougar riser with Prowler limbs and Megacams. The draw length is 30", draw weight is 66lbs, holding weight is 65%.

What is the minimum arrow weight for this bow?

Can I adjust the letoff?

It is supposed to go to 70lbs, but the most I can now get is 66. Would replacing the cables help? Is there anything else I can do to restore the draw weight? Or is it just "old and tired"?

When cables stretch the draw weight and the draw length decreases. Since it's pushing 20 years old I suggest getting new cables. If the cables aren't steel then you can get a good set from many different folks over on Archery Talk for not a lot of money. I don't know the Megacam but 65% let-off was typical for the time and I doubt there is a let-off adjustment. When comes to minimum arrow weight there are variables but with your draw length the standard IBO minimum of 5 grains per pound should be adhered to and an arrow weight 400 grains is plenty light. If you are really asking about the minimum arrow spine rating you can look that up on most any arrow manufacturers web site. A .300 - .350 spine arrow should work with an arrow 29.5" inches long at 65 - 70 lbs. with your 30" draw.

Take your bow, arrows and your release if you use one to an archery shop that has an experienced tech and see what he says. I'd hate to see something let go while you are at full draw. You need to work with someone that knows older bows and isn't merely going to tell you it's time to buy a new one. If there is an archery club near by you may be able to get good info from an experienced archer.

m00se
10-05-2010, 09:51 AM
When cables stretch the draw weight and the draw length decreases. Since it's pushing 20 years old I suggest getting new cables. If the cables aren't steel then you can get a good set from many different folks over on Archery Talk for not a lot of money. I don't know the Megacam but 65% let-off was typical for the time and I doubt there is a let-off adjustment. When comes to minimum arrow weight there are variables but with your draw length the standard IBO minimum of 5 grains per pound should be adhered to and an arrow weight 400 grains is plenty light. If you are really asking about the minimum arrow spine rating you can look that up on most any arrow manufacturers web site. A .300 - .350 spine arrow should work with an arrow 29.5" inches long at 65 - 70 lbs. with your 30" draw.

Take your bow, arrows and your release if you use one to an archery shop that has an experienced tech and see what he says. I'd hate to see something let go while you are at full draw. You need to work with someone that knows older bows and isn't merely going to tell you it's time to buy a new one. If there is an archery club near by you may be able to get good info from an experienced archer.

Thanks for the response. I had the string changed a couple of years ago. The cables are steel and appear to be in very good condition. I bought this bow new (ordered custom through a pro shop, actually), so I can account for its entire history.

A Martin tech told me today that an arrow weight of 5 grains per inch should be fine. I hadn't planned on going lighter than that, I just wanted to be sure I wasn't going to break something with a ~430 grain arrow. I've been shooting Easton 2317 tree limbs that weigh a little over 550 grains.

I had purchased a six pack of Carbon Hunter arrows from Cabelas last weekend, before the question of arrow weight was ever raised. Two of the inserts pulled partially out when shooting a foam target the next evening, so I took them back. I had had a generally bad experience buying them, and in complaining to the archery manager he asked if I knew the minimum arrow weight recommendation - so here I am. As it turns out, the Carbon Hunters are heavy enough not to hurt the bow.

So... next question... Gold Tip Expedition Hunters, or Beman MFX Team RealTree arrows? And can a TM Hunter rest go narrow enough for the Beman MFX arrows?

m00se
10-05-2010, 10:06 AM
Whoops... I meant grains per pound, not inch. :)

KStigall
10-05-2010, 12:35 PM
I used Gold Tip XT Hunters for a long time and still think they are good shaft for the money. I've never used the Expeditions. There's nothing wrong with the Beman shafts.

Since you will be having to tune everything with the new shafts I recommend getting a Whisker Biscuit. I started using the WB a few years ago after shooting a 300/47X 5 spot round with a WB. Get the one that lets you make vertical and horizontal adjustments. They cost about $70.

The problem with the TM Hunter rest with the carbon shafts is once you get the prongs close enough together to keep the shaft from falling through the arrow is setting up so high that it's real easy to bump off the rest. In a tree stand I found that extremely irritating.

Destroyer
10-05-2010, 06:40 PM
A Martin tech told me today that an arrow weight of 5 grains per inch should be fine.

For an old bow like that, were they joking? Ridiculous! :confused:

Keep above 6 grains per pound minimum and I don't recommend carbons for old bows at all.

m00se
10-05-2010, 08:33 PM
For an old bow like that, were they joking? Ridiculous! :confused:

Keep above 6 grains per pound minimum and I don't recommend carbons for old bows at all.


The arrows I'm looking at will be over 6 grains per pound. A little. As long as they make weight, why does material matter?

Destroyer
10-06-2010, 05:10 PM
Because carbons don't absorb enough vibration (energy) so they are noisier, much harder on the bow and because most buy the lighter arrows, it makes things worse even more.

The older bows are not made to handle them. :)

dragonsfire311
10-06-2010, 07:02 PM
If they work for you, I'd stay with the 2317's. My bow was built in '03 but I still shoot 2219's, work just fine on the critters I hunt, a little slower but speed isn't everything.

RLW
10-07-2010, 06:08 AM
Because carbons don't absorb enough vibration (energy) so they are noisier, much harder on the bow and because most buy the lighter arrows, it makes things worse even more.

The older bows are not made to handle them. :)

I think grs/lb has more affect on the adsorption ability than material, which the reason for the minimum grs/lb manufacturers now list for their bows in warranties.

I know Martin now states minimum arrow weight at 5 grains per pound of draw weight. I was thinking one of my 1996 Firecats said 6grs/lb.......I meant to look at that to verify, but forgot to.

The mid 1980's Firecat I had didn't even list a minimum, I assume because this didn't really use to be a problem back before light carbons when everyone shot long aluminum arrows like the typical stand-by 2117, 2216, heavier (2317), etc.
To get some more speed, I used to shoot "light" 2413 out of my '96 Firecat and those were over 7grs/lb. Even with overdraws that were popular for a while, I bet you had to work at much below 6.5grs/lb.

KStigall
10-07-2010, 09:16 AM
Because carbons don't absorb enough vibration (energy) so they are noisier, much harder on the bow and because most buy the lighter arrows, it makes things worse even more.

The older bows are not made to handle them. :)

:confused: I don't mean to be argumentative but your post doesn't make sense to me. Carbon shafts don't oscillate like aluminum shafts but that has nothing to do with absorbing the thrust or energy from the bow. The bow doesn't know if it's pushing a 430 grain, "x" spined carbon arrow or a 430 grain, "x" spined aluminum arrow. If there is a difference it is negligible.


m00se, if you want to start shooting carbons then go for it. You do have a longer draw length so don't try making the arrows real light. Going from a 550 grain arrow to a 430 grain arrow will gain you at least 30 - 35 fps which should make a noticeable difference in trajectory. I don't know how fast the 550 grain is traveling but I bet 30 fps is a big jump percentage wise.

m00se
10-07-2010, 11:43 AM
:confused: I don't mean to be argumentative but your post doesn't make sense to me. Carbon shafts don't oscillate like aluminum shafts but that has nothing to do with absorbing the thrust or energy from the bow. The bow doesn't know if it's pushing a 430 grain, "x" spined carbon arrow or a 430 grain, "x" spined aluminum arrow. If there is a difference it is negligible.


m00se, if you want to start shooting carbons then go for it. You do have a longer draw length so don't try making the arrows real light. Going from a 550 grain arrow to a 430 grain arrow will gain you at least 30 - 35 fps which should make a noticeable difference in trajectory. I don't know how fast the 550 grain is traveling but I bet 30 fps is a big jump percentage wise.

I have to agree, KStigall. Destroyer, it seems to me that the vibration should occur as the string recoils - after the arrow has detached. It makes sense that the weight of the arrow can make a difference, but not the material. Reminds me of another argument about whether a drill has more power with LiON or NiCD batteries... It also seems to me that a good set of Limbsavers could help dampen the vibrations from shooting the lighter arrows (I have Limbsavers on the Prowler).

The leader at this point is the PSE, but at 8.6gpi they are pushing the envelope. I figure all-up weight should be around 400 grains, well over the 5g/lb recommendation, but lower than I wanted. I guess I may have to bite the bullet (arrow?) and get Easton ST Axis (10.7gpi).

As a side note, I'm noticing that many arrows aren't made in anything stiffer than a 340.

RLW
10-07-2010, 12:13 PM
..........The leader at this point is the PSE, but at 8.6gpi they are pushing the envelope. I figure all-up weight should be around 400 grains, well over the 5g/lb recommendation, but lower than I wanted. I guess I may have to bite the bullet (arrow?) and get Easton ST Axis (10.7gpi).

As a side note, I'm noticing that many arrows aren't made in anything stiffer than a 340.

I'm currently shooting PSE x-weave 300, 29", (3) 4" AAE Vanes, w/100gr point out of my Bengal (spec listed in signature). Average of 6 was 399 gr and it is a little light on the front end.
I think these are really nice arrows, and likely to by other dozen, BUT also think the PSE 300 could be too weak for you at 31-32".

Cabela Carbon hunter 65/80
Beman ICS Hunter 300
Maybe the Gold Tip I thought you settled on in other thread?

m00se
10-07-2010, 12:33 PM
I'm currently shooting PSE x-weave 300, 29", (3) 4" AAE Vanes, w/100gr point out of my Bengal (spec listed in signature). Average of 6 was 399 gr and it is a little light on the front end.
I think these are really nice arrows, and likely to by other dozen, BUT also think the PSE 300 could be too weak for you at 31-32".

Cabela Carbon hunter 65/80
Beman ICS Hunter 300
Maybe the Gold Tip I thought you settled on in other thread?

I just found Velocity Hunters locally, and for a good price. One of my criteria was "What can I get on my lunch break at work" so I was calling only the close stores. I wanted new sticks to fling by this weekend. Unfortunately, weather and power outages conspired to chew up all of my time the last few days. No new sticks by Saturday :( But now I have more choices.

bfisher
10-07-2010, 01:21 PM
I just found Velocity Hunters locally, and for a good price. One of my criteria was "What can I get on my lunch break at work" so I was calling only the close stores. I wanted new sticks to fling by this weekend. Unfortunately, weather and power outages conspired to chew up all of my time the last few days. No new sticks by Saturday :( But now I have more choices.

I assume you are talking about Gold Tip Velocity arrows. These can be had in a 300 spine if that's what you want. As has already been mentioned with an older bow I would shoot for about 400 grains. This is almost 7 gr/lb and would make a very nice compromise between speed and stability, both for the arrow and the bow.

Good luck with whatever you choose.

m00se
10-07-2010, 01:25 PM
Going from a 550 grain arrow to a 430 grain arrow will gain you at least 30 - 35 fps which should make a noticeable difference in trajectory. I don't know how fast the 550 grain is traveling but I bet 30 fps is a big jump percentage wise.

550 was a low estimate. I haven't weighed the 2317s, but I'd guess them to be around 580 grains or heavier. 13.3gr/inch, 125gr points, three 4" vanes. If I go with the Velocity Hunters, my arrow weight will be around 400gr with 100gr points.

RLW
10-07-2010, 01:30 PM
550 was a low estimate. I haven't weighed the 2317s, but I'd guess them to be around 580 grains or heavier. 13.3gr/inch, 125gr points, three 4" vanes...........
Heavier, probably +/-635grs, so based on your given specs 9.6grs/lb

m00se
10-07-2010, 01:54 PM
Heavier, probably +/-635grs, so based on your given specs 9.6grs/lb

I wouldn't be surprised. I know Martin says it is OK, but do I really want to drop to ~400gr arrows?

Destroyer
10-07-2010, 07:27 PM
:confused: I don't mean to be argumentative but your post doesn't make sense to me.

Ok then. Energy can be any many forms, noise is energy, heat is energy, vibration is energy. When we shoot a bow a lot of the energy is wasted through vibration.

What I mean by carbons being noisier and harder on the bow is that carbon really has no absorption, and vibration sent through the arrow from the string doesn't get absorbed like the denser alloy shaft. The arrow is still connected to the string as the bow comes to a stop, this is how the arrow gets disconnected from the bow. Vibration then gets transferred to the arrow as well but because carbon doesn't absorb the energy, it goes back into the bow.

Now even if the arrow weight is identical, a bow will make different levels of noise, vibration, depending on the material. Shoot a wood shaft, a carbon and a alloy and take note of which one sounds the quietest. That is because the different materials absorb the energy, vibration, differently.

The material does make a difference.

That took a bit. :( There is more to this as well but my head hurts atm. The flexing has a bit to do with it as well.


Reminds me of another argument about whether a drill has more power with LiON or NiCD batteries

Nothing like this. :confused:

m00se
10-07-2010, 07:38 PM
I assume you are talking about Gold Tip Velocity arrows. These can be had in a 300 spine if that's what you want. As has already been mentioned with an older bow I would shoot for about 400 grains. This is almost 7 gr/lb and would make a very nice compromise between speed and stability, both for the arrow and the bow.

Good luck with whatever you choose.


I didn't see this before I posted my previous comment. This helps - I can get the GT Velocity Hunters up to 400grains. You sound confident that 400 grain arrows won't hurt my bow. I assume you have a lot of experience with Martin bows :)

I have LimbSavers on the limbs and a hydraulic stabilizer. Is there anything else you would suggest for dampening vibration?

RLW
10-08-2010, 05:59 AM
I wouldn't be surprised. I know Martin says it is OK, but do I really want to drop to ~400gr arrows?
I don't think it will come down to, if you want to or not, I don't think you will be able to get an arrow of proper spine that light at 31" or 32".

Assuming your 32" arrow has (3) 4" vanes, Easton Super nock, aluminum insert and a 125gr point.
The Easton XX75 2317 could weigh in at approx 635grs. (borderline +/-10% FOC balance)
The Beman ICS Hunter 300 comes in about 485 grains (good +/-12% FOC balance)

You've just dropped your arrow weight by 150 grains, and likely picked up a good 30 fps like KStigall mentioned earlier...........that is a very nice improvement.


FYI: I agree with Destroyer about all else being equal, different materials will make a difference in noise/vibration.........even different wood in guitars will make different sounds, but still believe arrow weight has a greater effect on vibration and/or damage if too light.

Shoot a high power rifle, with a light wood/synthetic stock weighing in at say 6lbs and fire it. Now replace only the stock with a heavy laminated stock to bring it up to 9lbs and fire it.........I guarantee your shoulder will feel that difference in recoil damage between 9lbs and 6lbs

Destroyer
10-08-2010, 08:30 PM
still believe arrow weight has a greater effect on vibration and/or damage if too light.

I agree. I would still rather shoot a light alloy than a mid weight carbon in a old bow though. :)