Fun with my Chrony...
 

FINALLY got the chrony set up to work indoors (had to get creative with light rigging). Only had time to do a bit of testing today, so I decided just to see what my bow is doing as is then with a heavier tip.

Bow- Diamond Hornet, IBO rating of 318 fps, 70#, 28" draw shooting a 350 grain ACC, 75 grains of which is the field point, only thing on the string is a TRU speed nock and 1 (long story) leech on the lower half of the string.

Shot a 5 shot string, got 285.5, 289.9, 287.6, 285.7 and 285.6, 5 shot average of 287 fps. Translates into 64' #s of KE. I think that' ll push a rocket through a deer :)

I had always heard the rule of thumb was 1 fps lost for every 5 grains of weight added, so I screwed on a 100 grain ft, and shot another 5 shot string. Got 282.9, 281.5, 281.5, 282.2 and 282.5, for a 282 fps average, dead on the 5 fps " standard" and 66' #s of KE. I plan to group test all my arrows again to see if they like the 100 grain tip better. If they do, I' ll gladly give up the 5 fps.

Over all I' m VERY happy with what the Hornet is producing. I should add that at 5 grains per #, the hornet is very very quiet and vibration free (does have limb savers and an 8" stealth).

Just for chits and giggles, I grabbed a full length Carbon Express terminator hunter 6075 with a 100 grain tip that I picked up at Wally World last fall when I was tinkering. It is whatever length WW sells them at, 3 4" vanes and it flew through at 250 fps... Not sure of the KE, as I have no idea what this shaft weighs. Jeff or anyone?

Next test I want to do is trade my black oem cable slide for the all white teflon one I had on the bow before I sent it to Diamond last year (general tune up and new string/cable). When they returned it, the had put a factory slide back on it. Curious to see what if anything the aftermarket virgin teflon slide does. I also want to see the fps difference between no leeches and two leeches.

Later...

RE: Fun with my Chrony...
 

Quick check of Bow Jackson-

CE Terminator Hunter 6075 with 100 grain tip and 3 4" vanes:

If 30" arrow weight is 504 and at 250 fps= 70' #s of KE

If 31" arrow weight is 516 and at 250 fps= 71' #s of KE

If 32" arrow weight is 528 and at 250 fps= 73' #s of KE.

Never have my digital scale handy when I need it...

Had to go measure... it was killing me :)

The CE is 31" , so #2 above applies if Bow Jacksons weights are on, which I suspect they are...

RE: Fun with my Chrony...
 

With my Solo Pat I lost 5fps with the sims white teflon slide.

It pulls my cable and string much closer to the riser than the bowtech slide - I suspect this extra friction is the reason.

RE: Fun with my Chrony...
 

How does a slide pull your cables closer to the risor? I would think the cables are gonna cross the rod at the same place regardless. Then they will slide back on the rod the same unless they are held up by some other force. Such as a MZE arm or other fall away cable. But then any slide would do that if attached to a fall away.

RE: Fun with my Chrony...
 

Rangeball, the teflon slides I use are good for about 2 fps over the standard plastic one that came on my bow. Not enough difference to worry about, but, they kept things quiet. The plastic ones can cause a definate squeal when sliding across the rod.

RE: Fun with my Chrony...
 

Nub - I meant closer to the rod

RE: Fun with my Chrony...
 

I figured that Rack. I just wanted to make you do a little more typing.;) I just looked at my Bowtech cable slide, it does put some distance between the cables and rod. I have a couple others in my tool box that are noticably lower profile. Should of bought a MZE with the new teflon slide. Quiet and most likely a speed increase.[:-]

Did they return your teflon slide?

RE: Fun with my Chrony...
 

RB,

That' s good performance for a 28" draw and that brace height. Those PF cams are quick!


The Terms in the 60/75 size weigh 10.7 grains per inch, insert is 12, nock is 8 or so,stock CX fletches are about 24 grains...

Warning though. I' ve seen those Term' s vary up to 20 grains from what they should. I had six from one dozen that weighed 440- something grains average, and another 6 from a different doz, cut/fletched same-same- that were in te 460 grain range...

RE: Fun with my Chrony...
 

Had a chance this am to slap the white teflon slide on. Increased 2 fps. I plan to leave it on for a while to see if it' s easier on my cables. Signs point to yes.

Jeff, I' ll weigh that arrow when I get a chance. Curiousity killed the cat, which makes it a ok in my book... :)

RE: Fun with my Chrony...
 

HEY!! I have a cat! and she heard that![:o]:D

RE: Fun with my Chrony...
 

Matt, if I wasn' t deathly allergic to cats, maybe we could talk... :)

Took the bottom (and only) string leech off, left white slide on, FPS jumped to 294 average on a 9 shot string... that' s with a 350 grain arrow.

WOO HOO!!!

Not bad for a 28" draw...

Bow seems just as quiet sans the leech, so they will stay off for now...

RE: Fun with my Chrony...
 

294 with a 350 grain arrow? That is about what I would expect considering that they advertise only a 1-2 fps loss with their use. That TS must weigh quite a bit over 400 grains to slow down your arrow speed by close to 33 fps over what you were getting with the 400 grain arrow.

It is fun to play around with the chrono and different setups...isn' t it? I usually end up fooling with it during the winter months when I have more time on my hands...:)

RE: Fun with my Chrony...
 

Frank, you lost me... TS?

You' re right. Playing with a chrony is very revealing... and fun :)

My bow is IBO rated at 318. Take off 20 fps for 2" shorter draw, and I should be getting 298. 294 is pretty close, and that' s with the TRU speed nock. A very easy to shoot and quiet 294 I might add...

RE: Fun with my Chrony...
 

My apology...TH. :D Terminator Hunter

Only a 4 fps loss with a setup that close to IBO specs (minus the draw and string accessory) is definitely impressive. I have found it to be alot worse on some bows.

All this chrony talk has me itchin' to pull mine out this afternoon to shoot a few arrows through it. I still have not chronoed the Pat SC or Rhino. :)

RE: Fun with my Chrony...
 

Frank, I told you a long time ago you should take a Diamond for a test drive :)

I brought my digital scale today. Soon I will know just what that TH weighs...

RE: Fun with my Chrony...
 

The verdict is in. The CE terminator hunter with a 100 grain tip weighed 500 grains, so it was putting out right at 70' #s of KE.

As far as being on spec, my ACCs were all within 1/2 a grain of each other. This was with the nock, uni-bushing, 3 4" feathers and insert only. Can' t say enough good things about these arrows...

Added the 100 grain tip to my ACC for a 375 grain arrow. With the white slide, no leeches it averaged 288 fps. Since they also fly to the same point with this head, I' m thinking about going with the 100 grain head I' ve been looking at. Can' t tell you what it is until I buy them, as they' re in limited supply and you' ll all want them :)

Well, maybe not Arthur... :)

RE: Fun with my Chrony...
 

Interesting read. My chrony stays out on my patio and gets " turned on" quiet often.
Aside from being fun to play with, they will drive you crazy[&:] on occasion. Beware the # are sometimes smaller than we wish they' d appear!!

RE: Fun with my Chrony...
 

Not if you are shooting a Bowtech :D;)[&:][:-]

(or a Bowtech cam in RB' s case :D)

RE: Fun with my Chrony...
 

Oh, but I am. Oh, but I am.................
Where I lack in speed I make up for it in KE.;)

Is 266 fast enough (65# pull 438 gr arrow)?
I guess it will have to do this year:D

Hmm, but I did just get some extra $$ for a 5 year service award, maybe some Beman 400' s are in order so I can also play the speed game??

RE: Fun with my Chrony...
 

All this talk of ACCs might make go get those 3-71s that Jeff sent me out so I can start smackin' nocks....:D

Now I have to go chrono those bows so I can throw some impressive KE and speed numbers around like the rest of you folks. :)

RE: Fun with my Chrony...
 

Sorry Frank, this thread is only for those with sub 30" draw lengths...

You at 31" and Arthur at 34" can' t play, you' ll put the rest of us and our set-ups to shame...

34" ... That' s just so wrong... :)

RE: Fun with my Chrony...
 

Well, you are half right. All the game that Arthur has got is his momentum figures....:D

RE: Fun with my Chrony...
 

475 grain CE TH (75 grain tip) pushes 256ish...

I have a 29" module that I want to put on to test. I can check out both a 350, 375, 475 and 500 grain arrow at this draw length, except one of the module bolts is just a hair to close to the limb for me to back it out clearly, so I' ll have to wait until I bring my porta press to work.

Shame on me. It should have been here a long time ago... :)

RE: Fun with my Chrony...
 

Ok...was wondering how you rigged your chrony for indoor shooting..seems the flourescent lighting always messes with the chronies I have used and had to settle for outdoors..Whats your secret?

RE: Fun with my Chrony...
 

Just saw my fawn rating..Geez I gotta get to atleast button buck status soon...LOL

RE: Fun with my Chrony...
 

Barebow, I had the problem you mentioned intially. Urinated me off to find out I had to buy another $30-40 part to make it work inside, so...

I suspended 2 75 watt light bulbs screwed into temporary light sockets (like contractors use to provide temporary lighting), one about 1' above each diffuser, stuck the ends of the socket leads into an extension cord, plugged it in, worked like a charm, for a grand total of $0 :)

RE: Fun with my Chrony...
 

Finally got the 29" module in, and chronoed the same arrow set ups (350, 375, 475 and 500 grains) to see what I could pick up. I was curious as one of the options I have is to continue shooting off the string like I currently am but adjust my mongoose to it' s shortest position which will allow me to utilize my same comfortable anchor point. Here' s the deal-

grns 28" DL 29" DL
350- 295 fps/68ke 300 fps/70ke
375- 288 fps/69ke 293 fps/71ke
475- 256 fps/69ke 264 fps/73ke
500- 252 fps/70ke 258 fps/74ke

I was shocked to only pick up 5 fps at an inch longer draw. Since I like the way the gator jaw fits so well at 28" , I can' t see any reason to shoot at 29" if I continue to use a lighter arrow, which I plan to do this season. Going up will require me to either go back to the GT hunters I have, which isn' t happening, or buy new ACCs, which is expensive for gaining a tad over 1.5% in fps.

On the heavier arrows, performance jumped up 6-8 fps, or 2-3% gain. Probably not enough added trajectory advantage to again warrant purchase of new ACCs.

What this exercise seems to have taught me is I' m very happy and confident with my current set up. I' m no longer wondering if I' m missing something. I also will never again use rule of thumb guesstimates such as " an inch longer draw length will get you 10 more fps" etc, as there are two many variables involved.

RE: Fun with my Chrony...
 

I' m a little surprised too.

Did you measure the draw length or are you just assuming it' s an inch longer? I' ve seen many modular bows that will measure say 28.75" w/ a " 28" mod, and then only be 29.25 w/ a " 29" mod.

Generally you will see about a 3 to 3.5% diff in arrow speed for every inch increment lost or gained in draw length. HOWEVER certain cams and bow designs gain and lose sometimes at very different rates. Solo' s especially. They tend be pretty efficient from abot 29 to 31" of draw, but lose big chunks of performance in shorter draws.

RE: Fun with my Chrony...
 

You did pick up 8 fps on the 475 arrow.
When I was quoting a 9fps gain, it was with a 29vs30" draw and shooting a 438 grain arrow.

My new Mighty mite#' s (just for redundancy sake)
29.5" draw, 65# pull 426 grain completed arrow - 28.75" beman ics340 **
272 average for 70ft/lbs ke!!

My previous speed was 266 with a 438-grain arrow. My increase was due to moving the string leech closer to the lower cam and keeping it there with a small nock placed just above it, and slightly reducing arrow weight.

I' m sure happy with the numbers for only pulling 65#, with my recent 4 wheeler wreck induced hurting shoulders/chest:( I doubt I could pull much more!!

**going to duravanes from bohnings dropped my arrow weight by 12 grains, this includes a cleaner fletching job then what they came with (messy[X(], excessive glue)

RE: Fun with my Chrony...
 

Jeff, I did just make the assumption that the mod added a full inch. Haven' t quite figured out how to measure myself at full draw yet :)

For what it' s worth, even if it is short or not a full inch, I don' t think I could shoot it any longer as I was pretty spread out as it was. I' m happy with the performance I' m getting at 28" , and the scott molded grip gator jaw feels fantastic, reminds me a lot of the solid feel the Winn glove gives you.