Hunting Washington Forum

Equipment & Gear => Archery Gear => Topic started by: norsepeak on March 14, 2013, 02:02:03 PM

Title: For all you archery experts.
Post by: norsepeak on March 14, 2013, 02:02:03 PM: So I was out shooting today, getting ready for spring bear and thought about a little experiment just for fun, so this is what I did. Weighed 4 arrows, then shot them through my chrony just to see what was going on, so take a look and see what you think. All arrows were shot from the same distance from the chrony. I shot the arrow each per set. So what does this info tell you? Also, can anyone calculate my Ke for me?

#1 434.8 grn

1. 304.1fps
2. 298.9 fps
3. 299.9 fps
4. 303.3 fps

#2 435.2 grn

1. 299.5 fps
2. 302.0 fps
3. 299.8 fps
4. 296.3 fps

#3 431.3 grn

1. 299.0 fps
2. 299.0 fps
3. 305.8 fps
4. 300.1 fps

#4 434.4 grn

1. 299.0 fps
2. 304.6 fps
3. 295.8 fps
4. 297.9 fps
Title: Re: For all you archery experts.
Post by: mtbiker on March 14, 2013, 02:18:36 PM: Lots of calculators out there. Here's one. http://www.eastonarchery.com/store/kinetic_calculator (http://www.eastonarchery.com/store/kinetic_calculator)

There should be a 1 fps variation for every 3 grains. With the margin of error of the crono, you look pretty consistent to me.
Title: Re: For all you archery experts.
Post by: norsepeak on March 14, 2013, 02:32:11 PM: I thought the same, seems to be pretty consistent. I thought the weight difference with arrow #3 would make more difference, but not so. According to the Ke calculator, I've got 89.5 lbs. Ke. Enough for a Cape Buffalo according to the website. Thanks.
Title: Re: For all you archery experts.
Post by: Holg3107 on March 14, 2013, 02:45:44 PM: your arrows are within 1% weight of each other. That's not enough difference for real visible change so your data really doesn't surprise me especially when you have a <1% difference in speed per arrow.
Title: Re: For all you archery experts.
Post by: mtbiker on March 14, 2013, 03:40:28 PM: Quote from: norsepeak on March 14, 2013, 02:32:11 PM
I thought the same, seems to be pretty consistent. I thought the weight difference with arrow #3 would make more difference, but not so. According to the Ke calculator, I've got 89.5 lbs. Ke. Enough for a Cape Buffalo according to the website. Thanks.

Yeah, that's some good KE, there. We all look forward to the pics of you and that Cape Buffalo you take down. ;)
Title: Re: For all you archery experts.
Post by: Smossy on March 14, 2013, 03:59:43 PM: Quote from: mtbiker on March 14, 2013, 03:40:28 PM
Quote from: norsepeak on March 14, 2013, 02:32:11 PM
I thought the same, seems to be pretty consistent. I thought the weight difference with arrow #3 would make more difference, but not so. According to the Ke calculator, I've got 89.5 lbs. Ke. Enough for a Cape Buffalo according to the website. Thanks.

Yeah, that's some good KE, there. We all look forward to the pics of you and that Cape Buffalo you take down. ;)
:yeah: :yeah:
Title: Re: For all you archery experts.
Post by: demontang on March 14, 2013, 05:20:21 PM: Looks pretty consistent to me. I came up with 86 for ke but its still more then enough :tup:
Title: Re: For all you archery experts.
Post by: norsepeak on March 14, 2013, 06:25:28 PM: It blew a shuttle T thru this guy last fall and stuck it in the ground 8"...so should do the trick on a fat blackie this spring.
Title: Re: For all you archery experts.
Post by: Smossy on March 14, 2013, 06:42:34 PM: Quote from: norsepeak on March 14, 2013, 06:25:28 PM
It blew a shuttle T thru this guy last fall and stuck it in the ground 8"...so should do the trick on a fat blackie this spring.
Nice, I cant WAIT to get my first deer.
Title: Re: For all you archery experts.
Post by: demontang on March 14, 2013, 08:51:27 PM: Nice how do you like the shuttle t?
Title: Re: For all you archery experts.
Post by: D-Rock425 on March 15, 2013, 12:02:17 PM: What arrows?
Title: Re: For all you archery experts.
Post by: RadSav on March 15, 2013, 01:37:05 PM: Just as in rifles...what's good for deer should be plenty for bear.

Your setup seems to be quite close in speed. Large variances in speed from slowest to fastest are caused by many things. Uniformity of nock throat is one many over look. You might number your arrows to see if the same arrow consistently shoots slow or fast. If one gets singled out try replacing the nock.

The biggest factor is usually movement at release or inconsistent back tension. Very common with caliper releases. If you pull too hard against the wall or bounce against the wall you will see a faster speed through the chrony. If you creep forward at release you will see a slower speed as well as a break down in your form which also leads to a low arrow placement.

Less common is string interference. Simple contact with the face can effect speed to some degree. Even more common is interference from arm contact. The shorter the brace height is the more common it is.

So, even though as stated your numbers are looking very close and performance should be quite consistant it does give cause to look at your shooting form. Spend a little time at each practice session shooting with your eyes closed. Concentrate on proper back tension, string interference and maintaining the proper capital "T" in your shooting form. A simple quiver full of arrows with your eyes close at the beginning of each session will greatly improve your consistency including the speed at which your bow shoots.

BTW - Dang nice deer!
Title: Re: For all you archery experts.
Post by: norsepeak on March 15, 2013, 09:02:55 PM: shooting the 340 Axis (30" +or- a little, 9.4 gpi) out of my Mathews Helim, 125 grain shuttle T's, with caliper release and string loop at 30" draw, trophy taker drop away rest. This is by far the nicest, smoothest bow I've shot in over 20 years of bow hunting. Very happy with the results so far. The shuttle T, was devastating on the buck, came out thru the shoulder on the off side.
Title: Re: For all you archery experts.
Post by: D-Rock425 on March 16, 2013, 07:52:18 AM: good set up :tup: