Hardest lessons to learn in archery – Watch the weight Or why we need to watch our weight

No not a comment on obesity in archery but a quick look at how weight in many different forms can effect archery, whether we are talking about the draw weight of your bow or the weight of the arrows used.

So when can too light be a bad thing, and again I’m not talking about the archers weight here or anorexic, but in fact arrow weights.

Before I launch into this article though I’d like to thank my guest co-author another Rob, Rob Cook.

Rob Cook

Rob Cook

As many of you know I’m a big traditional archer shooting wooden bows and wooden arrows, so when it came to checking my facts with carbon arrows and so on, so I enlisted Robs help. Rob was also one of the originators of the new Traditional Bow hunter class in the NFAS and has extensive knowledge on the bare bow scene.

Bow International ran an article a few issues back on the effect of arrows weights on arrow flight and I know other sites including The Push have talked about the importance of matching your arrows to the bow.

Too light an arrow and archers can encounter several issues. Light arrows can fly faster and some say further, but they can be affected by wind to a greater degree. also there may not be the mass weight to absorb the energy from the bow limbs on release as effectively. in essence its like a mini dry fire.

Most bow manufacturers will specify an optimum mass weight for your arrow and if you look on just about ever carbon arrow in production will give you an arrow weight in grains per inch

To give you an example of what I mean, a bow maker might say the arrow should be 9 grains per pound of draw weight, so for my draw weight of 45lbs that would be 405 grain arrow weight. Through a lot of trial and error I have found an arrow round 450 to 460 works best from the bow, anything below 420 and the bow becomes noisy  and the arrows don’t perform as well.

Rob has created this table of data on different arrow specs and weights for some of the more common arrows on the market. We’ve used a 100 grain pile in all the arrows below calculations and show two lengths 28 inches and 30 inches, so we can give a total weight. To keep it simple Rob has used a 45lb bow weight for spine as I used that weight in the above calculation. It should all make sense but if you have any questions let us know.

Manufacturer Shaft Type                    spine @28 Arrow Weight gpp spine @ 30 Arrow Weight gpp
Avalon TecOne 600 330 7.3 600 344 7.6
Beman Classic 600 367 8.2 500 434 9.6
Carbon Express Predator II 2040 354 7.9 2040 370 8.2
Carbon Express Heritage 75 388 8.6 90 424 9.4
Easton Carbon One 660 325 7.2 550 347 7.7
Easton Axis 600 340 7.6 600 355 7.9
Easton 5MM Axis Traditional 600 357 7.9 600 373 8.3
Easton ST Axis N-Fused Camo/Axis Trad 600 360 8.0 600 376 8.4
Easton Apollo 610 367 8.2 560 392 8.7
Gold Tip Traditional 600 373 8.3 600 388 8.6

 

So why is this so important and why am I bringing it up here on this blog?

The NFAS has seen a new bow style recently, that of Traditional Bow Hunter. This style allows archers to shoot carbon or aluminium arrows off the bow shelf (no arrow rests). It is seeing a number of traditional archers that shoot flatbow or hunting tackle which uses wooden arrows giving it a go. They are buying carbon arrows of the right spine but I wonder if they are considering the effect of shooting lighter arrows on their bows? I was discussing this with a couple of people including Rob, so we thought we would put this together.

It is worth remembering that a lot of traditional wooden bows have not been constructed to take ultra-light carbon arrows often used in target archery or are sold as cheap alternatives to wooden or aluminium arrrows. Please don’t get me wrong some bows have been constructed to take such arrows but not all.

N.B. Adding a heavier pile to the arrow will increase the overall weight but it will also change the dynamic spine of the arrow, making it more flexible or weaker.

So what can you do?

  • Check the weight of your wooden arrows and carbons so you know the difference.
  • Check what your limb / bow manufactures recommended weights are. Most if not all will have this information on their websites or would be happy to share it with you. After all they don’t want to see you trash your bow as it reflects badly on them.
  • Going for slightly longer arrows as this will increase the mass weight too, this is why we have included two sizes in the above table.

I hope this has proved interesting and helpful. I would like to say thank you to Rob for all his help and number crunching with this. He produced a load of data on different arrows in a long excel document, as well as speaking to several bow manufactures to check minimal weights.

Thanks for reading.

 

Question from a reader – Improving grouping

Last week I posted a response to a readers question concerning aiming and focus. This is  the second part of my response and in this I will try and address another question
I practice very very much and I can not reduce the diameter of my groups
I know this feeling all too well and I used to spend hours quietly practicing at the range at Black Arrow and now at home.

Reducing the diameter of the group comes with practice. Lots of practice in my case. It takes time and consistency in equipment and techniques.
Here are a  few tips I’ve picked up along the way. I  hope they help.

Know your Equipment

If your equipment is not consistent then you have a constantly changing variable to any practice you undertake.

If you shoot a takedown recurve each time you dismantle and reassemble your bow you run the risk of accidentally changing settings. Whether this be the bracing height or dropping twists in the string. So take care and time to make sure everything is right. I have found a camera phone invaluable aid for checking brace height or nock position. Set the bow up, making sure everything is right  and then take a few photos of the bracing height, nocking point etc. It provides you with a quick easy to check reference.

Photo of recurve set up

Photo of recurve set up

If you do change anything make sure you change one thing at a time. However if you change bracing height you might need to immediately change your nocking point as well.

Weather can play a part on equipment too. Traditional English longbow archers will tell you that in warm weather the bow will behave differently to when it’s cool.

Arrow weight and quality

  • Are all the arrows you are using straight and in good condition re nocks and fletching wear?
  • Do they weigh the same?
  • Do they really have the same spine?

I had one student who was struggling with grouping and when we weighed his arrows we found a huge weight variation which explained his issue at longer distances. Additionally, the spine shown on the boxes of wooden shafts  can vary, (in some cases we have found a 20lb variation in a single box that is theoretically ranged within 5lb.) This can be caused for a number of reasons from storage to temperature.

A good idea is to number the arrows and note where they hit. That way if you find one that always goes left or drops short you know it’s the arrow not the archer. I also make a note on each arrow how much they weigh in grains and match shooting sets of the same weight. (Definition of Grain)

This is obviously more of a problem with wooden arrows than with carbon or aluminium arrows.

Equipment consistency is easy compared to archers.

Are you consistent in draw, anchor and release?
If you aren’t being consistent here then getting a good group is impossible.
Light is right and going back sometimes to a lightweight bow means you can focus on draw, release and overall technique.

Take your time between shots don’t rush to shoot as your muscles take time to recover after each shot.  A rushed shot is seldom on target but can often infuriate you.

One technique I use is to start at short distance say 5 yards. And focus on bringing the group in. I then move back 2-3 yards and work on grouping at that distance.  Gradually you move further back. This builds an image bank in your brain of where you should be at different distances. I would practice at, 5,7,10,13,15,17,20,23 and  25 yards shooting 3-6 arrows. Not until I would get at least 5 arrows constantly in a group of 3 inch diameter would I move to next distance. This took months of practice and patience, lots of patience and quite a few replacement nocks. Some days I would shoot 40 arrows others 120 depending on how I was feeling and whether I could focus on the practice. no good practicing if you aren’t focused.

Jim Grizzly Kent recorded a video for YouTube a while back on cup shooting which is another good practice technique.
 Finally, if you can get a friend to video you shooting this might help identify any inconsistencies that you have (once you get past being self concious of being recorded). I am thinking of doing an article on the use of video in the near future.

I hope this helps once again thanks for reading.

Tips and Advice – screw in points

Getting the perfect matched arrow takes time and relies on a number of factors, from overall arrow weight,  to flexibility / spine of the shaft, fletching size etc. One of  these factors is the weight of the pile or point. A heavier pile makes the arrow flex more, whilst a lighter pile makes the arrow stiffer.

For this reason we have been trying to fine tune Sharons’ arrows (Easton X7) and have recently changed her points from glue in pins to screw in points with obvious inserts into the aluminum shafts. The X7 are great arrows, and work well from here bow but we thought we might get a slight improvement. By using inserts we have a greater access to different point weights to experiment with.

Sharon Shooting

Sharon Shooting

The old piles came in at 60 grains and the feeling was it might be making the arrow a little too stiff. So we spent sometime looking at alternatives. By the way we have looked at going for carbon arrows but Sharon preferred the X7 as Carbon ones, as the carbons came in too physically light for here bow.

I’ve used a 2 part epoxy glue to secure the inserts into the shafts, which appears to work well. We’ve opted for these inserts and points which we got from Bow Sports. The inserts are 8/32 with 9/32bullet points.

Arrow points and insert

Arrow point and insert

The one thing with we’ve discovered is that the screw in points sometimes work lose. Now the easy answer to this is to apply a little glue, the only problem with this being that if you need to remove the piles the only answer is to then heat it up to break the glues bonds, which will also break the bonds of the glue used to hold the insert in.

One trick I’ve come up with using plumbers tape or PTFE tape. I cut a small piece about an inch in length and then wrap this round the threaded bolt, then screw this into the insert in the arrow.

new pile and insert

New pile, you can see the tape wrapped round thread.

The result of using the tape is to make the threaded bolt a little tighter in the insert, so making it less likely to undo or loosen.

Technical Facts for those interested in weights etc

  • Old piles / nibs were 60 grain
  • Insert 14 grains
  • New screw in points 80 grain

Hope you find this of use and as always thanks for reading.