# Two Groups of ACC's



## Unclegus (May 27, 2003)

Are some of them DN series and some of them DM series? There's usually about five grains diff between DN's and DM's.... I have actually found as much as seven grains difference in the DN series from one dozen to the others. If you buy a dozen still in the wrapper, they are usually spot on.

Being a coal miner, I found a really simple solution. I just take the heaviest completed arrow and use it as my standard and then remove the nocks from the lighter ones and cut a strip of paper towell that makes up the weight difference and twist it up and stick it down the unibushing and then push it gently down the shaft with a strightened coat hanger. You can get all of them to weigh the same in just minutes. I've done this for years.....and they shoot well. The beauty of this is if you ever want to take them apart or redo them, you just take them apart and start over without much problem. The ACC without a doubt is one of the best, dollar conscious, trouble free arrows ever made. IMO:thumbs_up


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## sawdust2 (Jan 7, 2009)

*Thanks Unclegus*

I do have both series. This is something I had not paid attention to and it feels good to learn something new. I especially like the paper towel fix, it couldn't get any easier than that.

Thanks again

sawdust2


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## Kstigall (Feb 24, 2004)

A few grains of weight over the length of a carbon shaft isn't of much importance. At longer distances 5 grains at the point or at the nock may be noticeable depending on the distance and the abilities of the archer.


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## Brown Hornet (Aug 8, 2002)

Shoot em and see....like KStigall said 5 grains spread over the shaft isn't a big deal....but you will notice a shaft with 100 vs 105 grain points. 

Jesse and Reo could probably tell the difference....but more then likely only a couple people that post could even tell the difference and 90m. I sure wouldn't add paper to my shafts to get them to weigh the same. 

Spine is far more important then a couple of grains here or there.


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## FS560 (May 22, 2002)

Wow! The paper towel is a great idea. I am so sorry I never thought of it.

The neat part of it is that the strip of paper is so light that the whole 5 grains, or whatever, is distributed over the length of the shaft and does not change the static spine of the shaft. It is like adding back the weight differential between the light shaft and heavy shaft.

I do not have any shafts that need adjusting right now but I am going to weigh out a strip of paper towel to see if a strip is about a whole shaft length.

It might be interesting to test this on a HS. Wish I had one.


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## mike 66 (Jan 21, 2010)

*i agree with UNCLEGUS BUT!!*

I HAVE A TRICK////WITH A/C/C THE SAND IS OK BUT WILL MOVE. TRY MY SECRET............ TRY BLACKHAWK INSERTS TO SOLVE WEIGHT PROB UNC. I AGREE 100%ON TYPE SHAFT BUT . WHAT I LIKE IS ..............THE PIN NOCKS. FOR THEM ... THEY WILL THROW YOU OUT OF X BUT NO ROBIN HOOD.WITH PIN. NOCKS INSTEAD OF UNI MY TRICK .. HOW COOL


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## Unclegus (May 27, 2003)

Coal miner mentality........Came up with that one back in the day of slow bows when five grains meant the difference between a spot and a pro line four..... Maby it will get back to that level if we are shooting for a six instead of fives....along with floating shafts......:wink:


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## Robert58 (Oct 5, 2002)

mike 66 said:


> I HAVE A TRICK////WITH A/C/C THE SAND IS OK BUT WILL MOVE. TRY MY SECRET............ TRY BLACKHAWK INSERTS TO SOLVE WEIGHT PROB UNC. I AGREE 100%ON TYPE SHAFT BUT . WHAT I LIKE IS ..............THE PIN NOCKS. FOR THEM ... THEY WILL THROW YOU OUT OF X BUT NO ROBIN HOOD.WITH PIN. NOCKS INSTEAD OF UNI MY TRICK .. HOW COOL


What pin insert so you buy for 3-28 ACC shafts?

Robert


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## jarlicker (Jul 29, 2002)

I would strongly recommend that you dont worry about the overall weight differences between the shafts. Just make all the point weigh exactly the same. 5 grains at 80 yard would hit about a 1/4 inch apart if everything else was set up perfecly. Do you feel you can hold that good to notice the differance. Getting perfect nock alingment over all the shafts is where I would put all my effort. Select your arrows by which ones group the best together.


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## Scott.Barrett (Oct 26, 2008)

I'd keep one set for practice and the other for tournaments. You're seeing a 3fps change in speed and that will be noticeable at longer distances.


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## Brown Hornet (Aug 8, 2002)

I agree with Jarlicker. :wink:

Shoot em all and I bet you won't be able to sell the difference on target :wink:

Man 241 is slow though......so the difference of 2-3 fps for me is very minimal....for you it may be a different story.


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## sawdust2 (Jan 7, 2009)

*Thanks*

Thanks for the replies. My biggest problem now is getting out to shoot and seeing how things go. As to the speed, I looked more at point weight for FOC than fps, maybe a mistake. Also, due to a sore shoulder I dropped from my usual 57# to 50# so unless something changes there I'm stuck. My Lightspeeds are a possibility for lighter shafts but I wanted to try the ACCs that I had on hand. So is it better to up the fps with lighter points and less FOC or lighter shafts and more wind drift?

Thanks

sawdust2


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## FS560 (May 22, 2002)

I have not loaded any arrow tubes with paper towel yet, although I did weigh out some paper towels and toilet paper.

To do this, I would want the paper to be the whole length of the arrow tube less the point shank and nock pin shank.

Paper towels are too heavy and would require cutting a very narrow strip.

I weighed out some toilet paper and found that, with the one I weighed, that a strip 27.5 inches by 0.5 inch is 5.33 grains.

I think I could get that into a shaft and strung out nicely without wadding it up.

Once the shaft is sealed up at both ends, the paper will not move around, and therefore will be stable.

Do not misunderstand me here, I still prefer to have the shafts to be the same weight range. But this is something you can do if your shafts are severly mismatched.

Unless and until all arrow shaft manufacturers note the weight range on the bundle, this problem will continue.

Even with ACC shafts, there are variations within the same series.


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## montigre (Oct 13, 2008)

Seems to me that if an unsecured strip of paper is placed within the shaft, the forces of the arrow through repeated cycles of acceleration and deceleration would eventually cause the paper to wad and throw off the intended equilibrium. Kind of like a coup contre coup injury sustained by the brain during an automobile accident.

Would this effort really be worth it if the arrows otherwise spine out properly??? I'm confused.....


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## Brown Hornet (Aug 8, 2002)

montigre said:


> Seems to me that if an unsecured strip of paper is placed within the shaft, the forces of the arrow through repeated cycles of acceleration and deceleration would eventually cause the paper to wad and throw off the intended equilibrium. Kind of like a coup contre coup injury sustained by the brain during an automobile accident.
> 
> Would this effort really be worth it if the arrows otherwise spine out properly??? I'm confused.....


Exactly.....and no the effort isn't worth it. 

and nobody that has posted in this thread holds or shoots good enough to truely tell the difference anyway in the weight difference at even 80 yds...


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## Brown Hornet (Aug 8, 2002)

sawdust2 said:


> Thanks for the replies. My biggest problem now is getting out to shoot and seeing how things go. As to the speed, I looked more at point weight for FOC than fps, maybe a mistake. Also, due to a sore shoulder I dropped from my usual 57# to 50# so unless something changes there I'm stuck. My Lightspeeds are a possibility for lighter shafts but I wanted to try the ACCs that I had on hand. So is it better to up the fps with lighter points and less FOC or lighter shafts and more wind drift?
> 
> Thanks
> 
> sawdust2


I am a little confused here....either your not really sure of your actual FOC with your arrows or you don't understand FOC.

Your going to have a higher FOC with your Lightspeeds then your ACCs. 

your 3-28s weigh 8.1 grains per inch
your Lightspeeds weigh 6.5 grains per inch...assuming your shooting 500s since that is the spine of your ACCs.

your arrows being the same spine you will still need the same point weight to give you the same spine....if you have a 100 grain point in both arrows your Lightspeeds are going to be faster since they are going to be around 30-40 grains lighter....but they will also have a higher FOC because they are lighter. Even going with say an 80 grain point in the Lightspeeds and 100 in the ACCs your FOC will still probably be higher Lightspeeds


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## TNMAN (Oct 6, 2009)

*I think I can tell*



Brown Hornet said:


> nobody that has posted in this thread holds or shoots good enough to truely tell the difference anyway in the weight difference at even 80 yds...




Not trying to be smart, but pretty sure I can. It's simplistic, but the difference in flight time between 241 and 244 fps over 240 feet multiplied by 32 ft/sec/sec says difference in drop will be around 4.7 inches. That math does not take into account several variables, but it should be close. Shoot them and see.


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## TNMAN (Oct 6, 2009)

*numbers*

Looked at the numbers some more. Six grains difference should be around 2 fps difference on average. I used the 3 fps difference as given. Chono numbers can be tricky. If the actual difference is closer to 2 fps, then the drop would also be reduced by approx 1/3, which means 3 in. drop. That is getting harder to tell at 80. Maybe I can't tell the difference shooting. Shoot them and see is still pretty good advice.


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## X Hunter (Jan 11, 2007)

Brown Hornet said:


> Exactly.....and no the effort isn't worth it.
> 
> and nobody that has posted in this thread holds or shoots good enough to truely tell the difference anyway in the weight difference at even 80 yds...


So a Vegas champion dosent hold that well???

anybody know who I'm speaking of??


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## FS560 (May 22, 2002)

montigre said:


> Seems to me that if an unsecured strip of paper is placed within the shaft, the forces of the arrow through repeated cycles of acceleration and deceleration would eventually cause the paper to wad and throw off the intended equilibrium. Kind of like a coup contre coup injury sustained by the brain during an automobile accident.
> 
> Would this effort really be worth it if the arrows otherwise spine out properly??? I'm confused.....


I do not think the strip of paper is adequately heavy to have enough inertia to provide any degree of setback inside the shaft.


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## Brown Hornet (Aug 8, 2002)

X Hunter said:


> So a Vegas champion dosent hold that well???
> 
> anybody know who I'm speaking of??


No he doesn't anymore....and I am pretty sure he well tell you the same thing :wink:


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## sawdust2 (Jan 7, 2009)

*Back To FOC For A Minute*

Maybe I don't understand FOC so here are the specs on the two sets of arrows I have mentioned so there is no speculation. (These numbers are from the Gold Tip FOC calculator.)

3-28 ACC's....349 gr finished weight..100 grain point...11.36% FOC
..................349 gr finished weight..106 grain point*.11.97% FOC

Light Speed 500...302 gr finished weight..90 gr. point..10.45% FOC

* max weight correction to achieve a given total weight, 6gr.

I do understand that the FOC is changed by adding the compensating weight to the front of the arrow. I also understand that shooting different weight arrows will effect the point of impact, which has already been calculated. Now the question is what effect will two different FOC have on the point of impact for two arrows of the same weight shot from the same bow? In this case a difference of .61%. Is this something for which there is a calculation?

I'm curious as to where the emphasis should be for trying to build a matched set of arrows.

Thanks 

sawdust2


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## 10xring (Jun 10, 2003)

Using On Target 2 and just figuring out some quick numbers....

205.2 grain shaft with a 100 grain point - 80 yard trajectory = -75.57"
199.5 grain shaft with a 106 grain point - 80 yard trajectory = -76.29"
199.5 grain shaft with a 100 grain point - 80 yard trajectory = - 74.9"

Just about a trade off in trajectory changes.


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## sawdust2 (Jan 7, 2009)

*Thanks 10xring and TNMAN*

It looks like the difference in arrow weight is a larger factor in difference of POI than the difference in FOC. The calculated 3" difference in POI at 80 yds from TNMAN as a result of weight,and therefore fps, is more than three times the POI difference calculated by 10xring for the same weight arrows with the different FOC.

This makes sense to me, if not to anyone else,and given that no one can tell the difference anyway I'm leaning toward stuffing some paper towel through the nock end, tamping it in place and getting the weight right.

Thanks

sawdust2


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## Unclegus (May 27, 2003)

I knew you'd see it my way......:wink:....BTW, what speed are we talking about with these impact numbers?????


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## FS560 (May 22, 2002)

And I suggest that it is not necessary to stuff it in and tamp it in place. I would cut a thin strip of toilet paper the length of the shaft less the point shank and nock adapter shank. Then drag it through with a coat hanger. The toilet paper is lighter and unlikely to move in the tube during use. The friction inside the shaft is likely greater than the inertia of the paper itself during sudden decelleration at the target.

This method will have the least effect on FOC.


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## sawdust2 (Jan 7, 2009)

*The TP Method*

Sounds good also. I'm quite happy with the info that has been generated from this thread. It all seems useful, practical and easy enough to do. Archery to me is fun even when you can't be shooting. Now back to balancing out a few more arrows and building another scope, including the lens this time.

Regards
sawdust2


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## TNMAN (Oct 6, 2009)

*ballistic calculator*

I ran across this last nite in Gen Pop. Haven't played with it much, but it might be useful.

http://home.att.net/~sajackson/ballistics.html


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