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They ask me amo cut lenght and nock model used for meausurments

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6.3K views 27 replies 6 participants last post by  FilippoITA  
#1 ·
Good morning to all,
Im buying my first arrows online (usually i go to my local archery shop) but since here in Italy we are all in a very strict quarantine i cannot go and get them.
Im buying them from Merlyn Archery Uk model Timber Creek classic shaft.
When i choose the number i want they ask me 2 questions:
Amo cut lenght (inches) : I dont know what this is i just know that my bow is 58'' amo (its a bear archery grizzly 55lb if this can help)
and then they ask me: NOCK MODEL USED FOR MEASURMENTS: (i dont really know what this is please help me)
Thanks for spending your time reading this, thanks a lot.
 
#2 ·
Good luck with the situation in Italy glad you are healthy. AMO cut length is how long do you want the shafts to be full lenght (whatever that is for them) or do you want to cut it shorter? Your draw length is important here as you don't want to draw they arrow past the center of the shelf. Usually shafts are 30-31 or 32 inches so normal draw length of 28 inches would have them cut to 29 inches or so (that is personal preference territory). Cutting the shaft also in effect raises the dynamic spine of the arrow so there are tunning issues that could come into play with AMO length. Nock size has to do with serving diameter-- in that you want the nocks to fit snuggly but not to tight and absolutely NOT loose on the serving string. If you have calipers get the serving diam and that will help them determine nocks or if you know the brand of nock currently in use that might help as well.
 
#3 ·
About the coronavirus im healty thanks for asking but i live in one of the hardest hitted city and many many people here died (mostly older than 65 years old).
Anyway your answer was 100% exhaustive thanks so much, now im free to order without any problem!
Take care and do not by any mean undervalue the virus!
Have a good day and thanks again.
 
#4 ·
woof’s answer is not quite complete. The shop is asking you how long you want your arrows to be cut.

AMO length refers to the length of the arrow measured from the groove of the nock to the actual cut on the shaft. Because different model nocks have different lengths, they want to know which model of nock you are using so they can make an exact cut to your specifications.

If you do not know the nock model, you can ask that they cut the arrow shaft itself (not including the nock) to your requested length. In that case you should specify “cut to cut” or “shaft length not including nock”.
 
#5 ·
If your existing arrows are working, just measure one of them. I'm pretty sure amo lenght they're asking for is von(valley of nock) to bop(back of point). Only reason I can think of they would want model of nock used is if they are not supplied with arrows, or you intend to different than ones supplied.


Steve
 
#8 ·
ahhh ok about the arrow lenght i already got it but about the nock then i have a new question:
I have to buy a new string from the too so i have no nock that can helps me making this measurment.... can i e mail them and tell them to use as example the serving string and a stanrd nock they have for help me out?
Why is traditional archery so complex in every possible way....
 
#10 ·
It’s not traditional that’s complex, it’s the same for all archery disciplines.

Nocks are cheap. Just ask them to supply a couple of dozen new nocks of any decent brand for your arrows, and make the string suitable for those nocks.

Or, if you don’t know the brand of you nock, just post a good close-up picture of one and we can tell you what it is.

What model and size of shaft are you ordering?
 
#11 ·
(Timber Creek classic shaft from merlin archery.. i cant post the link because im a very new member) im ordering this one 340 for 30'' cut (experimental) or the more ortodox 400 for 29'' cut since my draw is about 28 1/2
But i just want to headbutt the wall at this point since ordering an arrow full of components online requires a 8 years specialisation university degree ahahahhahaha
 
#13 ·
WRONG arrow for 55 lb recurve bow, with 28.5-inch draw length.
IF your recurve draw length on the 55 lb bow REALLY ends up 28.5-inches....I doubt it, because most new recurve archers cannot achieve full draw length, but if somehow you can reach
full draw properly, at 28.5-inches of DL, you will get 56 lbs on the fingers.

58" AMO bow, assuming a 8.25-inch brace height,
assuming 100 grain screw in field point,
assuming the aluminum insert is installed in the front of the arrow

the 340 stiffness arrow is off the charts stiff, and will not work...meaning, the arrow will fly massively crooked left, if you are right handed traditional archer, if using 100 grain screw in field point.
For the 340 stiffness arrow to work, at 30" cut, you would need 300 grain screw in field point...IF you use a plunger.

the 400 stiffness arrow is also off the charts stiff, and will not work...meaning, the arrow will fly massively crooked left, if you are right handed traditional archer, if using 100 grain screw in field point.
For the 400 stiffness arrow to work, at 29" cut, you would need 200 grain screw in field point...IF you use a plunger.

the 500 stiffness arrow is more appropriate. What does THAT mean "more appropriate"? If you are right handed traditional archer, if using 100 grain screw in field point, arrow will fly straight.
For the 400 stiffness arrow to work, at 29" cut, you would need 100 grain screw in field point...IF you use a plunger.


How could you POSSIBLY know this? I teach recurve and compound.
BUT, you have not seen me.
Yes, and I have major doubts you can shoot a 55lb recurve bow.
 
#12 ·
58" amo Bear Grizzly 55 lb recurve bow.

Since you are buying FIRST arrows, I have to also assume this is your FIRST recurve bow.
FIRST recurve bow at 55 lbs is a REALLY BAD idea.

FIRST recurve bow should be 20 lbs or 25 lbs, so you can build proper form and accuracy. Please consider purchasing a 25lb recurve bow to start.
Then, you purchase the appropriate bowstring for the 25 lb recurve bow (depends on the AMO size). Beginner 25 lb recurve bows are usually 62" amo.
So, you would need a 62" amo bowstring, which is actually 58 inches long or 58.5-inches long.

Then, you purchase arrows that are the appropriate diameter for the 25 lb recurve bow. That means you need an arrow that is LONG enough to be safe to shoot.
You need an arrow outside diameter that is SMALL enough (bendy enough) that is appropriate for a 25 lb beginner adult recurve bow.
Then, you need the appropriate point weight, for the beginner arrows that are LONG enough for an adult to shoot.

Since you are isolated in Italy, then, recurve lessons are not possible for you. What is your wingspan measurement?



What is your arm span measurement (middle finger to middle finger horizontal measurement), with arms horizontal?
We take this horizontal measurement, and divide by 2.5, to get a reasonable estimate of your draw length. This formula is not ideal, but gives an idea of your RECURVE draw length.

So, let's assume you have a 28-inch recurve draw length. Then, the Bear Archery Grizzly 55 lb bow will create 55 lbs of force on your fingers.
WAY WAY too much pounds on the fingers for a first time recurve archer. MUCH better you purchase a 2nd bow, a 25 lb limb RECURVE beginner bow.
IF your RECURVE draw length is 28-inches, then, the 25 lb beginner adult 62" AMO recurve bow, will deliver 25 lbs on your fingers.

What about the bowstring for the 62" AMO bow?
You contact Merlin Archery in the UK, and order the 62" AMO bowstring.
What about the nock and arrow? Since your recurve draw length will CHANGE with enough practice...this is true for ALL beginner recurve shooters,
we need an arrow LONG enough to be safe for you to shoot, regardless of how much your recurve draw length evolves, during your first year of shooting.

I recommend the Easton 1716 aluminum arrow. WHY? Because this is the SMALLEST outside diameter arrow, that allows installation of a field point insert.
What is this? This is an aluminum barrel that is installed in the front of the arrow tube.
WHY is this important? You can then use field points, that are threaded, to fit into the aluminum insert in the front.
WHY do I need field points that screw into the front of the arrow? The points are inexpensive and you can purchase multiple point weights. MORE point weight in the front, makes the arrow weaker.
LESS point weight in the front, makes the arrow stiffer.

SOOOOO complicated, this traditional archery.

WHY does weaker or stiffer arrow matter? WHY should I care? Depending on how far you pull back the bowstring (length of bow arm and string arm),
you will create more or less pounds on the fingers. So, when you select the correct point weight in front, for the Easton 1716 aluminum arrow, your accuracy improves TREMENDOUSLY.
When you shoot accurately, your enjoyment for traditional archery also grows TREMENDOUSLY.
 
#14 ·
I really appreciate that you had the care for me and my safety for post this all.
But i practice archery with recurve bows since 3 years.
The first year i used a 20lb bow, then a 35 lb bow, and now i use the bear 55lb and i never had never never half of a problem keeping that librage with my arms and my shoulders, they never hurted once and my muscles never complained. Just my fingers the first days of training.
I never buy arrows online because if i can buy from local italians shops where i just go there and they already know me they make me a good price and the arrow is already personalized why should i bother to take all the massive information in english and get them in my mind?
Anyway thanks again for getting interested about my safety, appreciate it Sir.
 
#15 ·
Plus i practiced a truly truly heavy sport wich is not archery for 4 years wich really toughned up my muscles (also the 3 right hand fingers for the stance wich is needed in a certain role in that sport) and i'm 1.92 meters tall and weight 91 kg.
Soo again i think to know what my body can handle and what he cannot.
Thanks again.
 
#18 ·
If you can explain me why i should still select 500 over 400 or 340 i would be really glad.
Briefly, the arrow flexes as it passes the bow. You can see this in slow-motion video - many examples on YouTube.

There is a relationship between the stiffness of the arrow, as designated by the spine, and the period of vibration of the arrow. Stiffer arrows vibrate faster, so for a bow that sends an arrow past the rest faster, you need a "stiffer" arrow with a faster vibration period, and for a slower bow, the opposite, a "weaker" arrow.

You can change the vibration period of a specific stiffness arrow to match your bow by changing the shaft length or the point weight. Longer arrows or arrows with heavier points, vibrate slower. Shorter ones with lighter points vibrate more quickly.

So, in order to roughly match an arrow to a specific bow, the bow draw weight, your draw length and overall arrow length are the minimum specifications you need to know in order to select an arrow. More information would be better. Manufacturers' charts are a starting point only for selecting an arrow.

But only a starting point. There are many other variables to consider, such as the overall bow design and quality, brace height, string material, the archer's release technique, etc, all of which have smaller but significant changes to the speed at which the arrow passes the bow. A cheap bow with a high brace height and poor string used by a beginner will need an entirely different arrow than a top end bow of the same draw weight, with a quality string, short by an expert.

Experienced archers such as Alan (and myself) can give you a good idea of what is most likely to work best for your specific setup, simply because we have seen many, many examples of what works or does not work for ourselves and many archers we have assisted.

In your case, based on my experience and given only the information you have provided, either a 29" 500 spine with 100-125 grains point, or 30" 400 with 125-150 grains point seems reasonable.

And no, the 500 will not break in half, and there isn't an arrow on the market (anywhere near the spine you need) that is light enough to cause damage to your limbs.
 
#20 ·
So, I recommend the 400 spine carbon arrow, if you want carbon arrow. Cut 29.5 raw carbon tube (end of carbon to end of carbon).
Have the aluminum insert installed for you. Then, you can select a wide range of screw in field points. I think the 200 grain field point will give you best results.
You can try 175 grain field points. You can try 150 grain field points. Depending on how clean your fingers release technique is, depending on how consistent is your recurve draw length,
will control what point weight works. Field points are available in all kinds of weight, one dozen pieces per set.

The 58" Bear Grizzly bow will work with a 54" recurve bowstring, according to Bear Archery.

The 400 spine carbon arrow, with 200 grain screw in field point, and the aluminum insert will weigh approximately 501 grains, total arrow weight, if you use feathers.
This works out to 9.11 grains total arrow weight, per pound of weight on your fingers...if you have 55 lbs on the fingers. If you pull the complete 28.5 inches of draw length, you will have 56 lbs on the fingers.
501 grains total arrow weight is safe for your Grizzly wooden recurve bow.

Since there is no hole for a plunger, then, you have to rely on getting the point weight EXACTLY correct, for best results.
 
#21 ·
Wow thanks so so so much i've watched both the videos, and now i've maybe understood why my string broke 2 days ago, it's because i think that my arrows are way way too light (i have a 100 grains point right now) hopefully after thousands of arrows my bow is not really that damaged (ouch).
I got my arrows made by the local archery shop for me and he always said that 100 grains were more than enough..... now that is a false statement if i read what you just said, i will never never go back again to that shop... never again.
I have a question for the feathers, i'm now using 4'' inches feathers, are them ok or the shop guys failed also that?
Anyway you probably saved my bow from getting some serious damage in the long term.
With the new arrows i will buy i'll do the test shown in the video.
So reassuming everything i should get: 400 spine, 29.5 cut to cut and try a range of screw in points from 150 to 200.
Now that i think about it my arrows always went far left but the archery shop guy told me that was ok and that i should compensate aiming more at right................(this was also the cause of why i started to inclinate my bow when shooting so that i will compensate more hahahahahahahah.
Thank you again so much.
 
#22 ·
Now im a little bit worried that thoundands of shots made with my bear using those really light arrows damaged my bow........
There is any method to find out if the bow god damaged? (visually it is perfect, and when i draw i hear no sound and i notice no difference in the stiffness of the libs)
Its unbelievable how a professional guy with an archery shop was able to give me such a totally wrong screw in point that weight at least 100 grains less, he just lost a customer.
 
#23 ·
Ok so i hope that this will be the last help that i need for my arrows setup:
On merlin archery i found the shaft:
https://www.merlinarchery.co.uk/bearpaw-penthalon-shafts-traditional-black.html i would choose 400 spine and 29.5''cut to cut
The 200 grains tip: https://www.merlinarchery.co.uk/bearpaw-combopoint-stainless-steel.html
The insert: https://www.merlinarchery.co.uk/bearpaw-penthalon-speed-insert.html 246 one so it weights more just to be sure hahahahah
the nock: https://www.merlinarchery.co.uk/bearpaw-hunter-nock.html
and the feathers : https://www.merlinarchery.co.uk/bearpaw-feathers-rw-5-shield-barred.html (dont know if 4'' or 5'')
I hope this is the last question i have for this impossibile task to assemble an arrow from 0
Thanks again
 
#24 ·
The 200 grain tip on that arrow MIGHT (emphasis on might) be just a bit heavy. I would purchase at least one 150 grain, and one 175 grain tip and try them all and see which one your bow likes the best.

4" feathers should be fine. Once the arrow is properly tuned to the bow, the feathers don't do a whole lot to stabilize the flight.

I sincerely hope that your bow is not damaged in any way. You should be able to do a visual inspection and tell if the limbs are twisted in any way.

Once you have the correct arrow, it should hit where you are looking. For me there is only one shop that seems to know anything about recurve bows in my area. Everything else I have had to study and learn from the internet. You can be over run by too much, even though it's good, information. Try not to let it exhaust you, good luck and happy shooting!!!
 
#25 ·
Perfect, so i try one 150 the other 175 and the last 200.
One more question about the string, i broke mine few days ago (the one wich came with the bow itself) being a Bear Archery grizzly recurve Amo 58'' i should get a dacron flemish right?
but with how many strands? the one who was sent with the bow was 16 strands, but i found one made by bearpaw wich has 14 https://www.merlinarchery.co.uk/bearpaw-traditional-flemish-string-14-strand.html
This should be perfect with the 55 lb bow and the bearpaw made nock right?
So all assuming this should be a proper made arrow plus string.... cant believe i have maybe finally made this impossible mission ahhahaha