170 fps w/ ACS-CX

snag · December 21, 2007, 07:57:00 PM

I weighed the arrows w/ 125 gr. tips they are 550gr. The chrono is working perfect. Tested it again...same results.

snag · December 21, 2007, 08:01:00 PM

What I don't understand is when I put more weight up front the arrow flight gets worse. With 5575s you should be able to shoot with a lot more weight than only 125gr. I lowered the brace height, as Larry recommended, to 7". Nock height is 5/8". I need to bring nock height up though.

MRD · December 21, 2007, 08:01:00 PM

What do the 55/75 weigh per inch? I wouldn't think you could get an arrow that heavy with only a 125 gr. field point.

Mark

snag · December 21, 2007, 08:09:00 PM

Yeah, their scales must be off! Without the tips that works out to over 14gr per inch. Can't be!

snag · December 21, 2007, 08:12:00 PM

I have never had a bow that was so difficult to set up and tune with arrows. It is cut 3/16" past center w/ a plate that brings it back to center. So, it should be able to shoot a wide range of spines well. I'm about ready to put the carbons away and bring out aluminum or wood. Anyone want a kingwood riser ACS-CX with 2 sets of limbs?

MRD · December 21, 2007, 08:32:00 PM

Wait til you get the Morrison limbs for that new riser of yours. It is WAY easier to shoot and set up. Well, it was for me, anyway!

Mark

vermonster13 · December 21, 2007, 08:42:00 PM

Mine really likes Axis 400s.
But hey if you want to give it away, I'll PM you my address.

Jeff U · December 21, 2007, 09:00:00 PM

QuoteOriginally posted by snag:
... I am using the chrono at the local archery shop so I know it is right on.

Does the shop regularly calibrate it? Anybody know how you calibrate a chrono?

I'd try a similar draw weight bow through the same chrono using the exact same arrow.

If that bow also seems a little slow, it could show a chrono issue.

kennym · December 21, 2007, 09:06:00 PM

We tested one of my bows indoors last winter,got some waybad fast #s,put a worklite up over it and then it read the same believable #s as the other one we shot outdoors...........

myshootinstinks · December 21, 2007, 09:19:00 PM

I owned an Adcock ACS/CX, 53#@28" that consistantly shot 185-190 fps w/ 5575s, I draw 28". Don't recall the arrow weight but I remember using the brass weight behind the insert along w/ 125gr tip. I'm guessing the weight was close to 500 gr.
It was a quick bow but a fussy one as to spine & arrow selection.

Big Sneaky · December 21, 2007, 10:27:00 PM

I've got an ACS CX that is 64" 53# @ 30". Shoots a 340 black max with 225 gr insert and head that weighs 566 gr. It shoots 'em 180-183 fps every time. 7 1/4" brace height and 5/8" nock set. But, I have another one that is 64" 58# @ 30 shooting a 300 axis that weighs 590 and it only does about 185-187. I had a friend who had one that was 57# @ 27" and it shot a 490 gr arrow at 170 fps. He wasn't impressed either so he sold it. The only thing we could figure was with his shorter draw, he wasn't getting the full power stroke that the limbs are capable of. I havn't had any trouble with tuning either of my bows except that they took a stiffer spined arrow than I would have guessed. I'm sorry your having so much trouble.

Cade

SOS · December 21, 2007, 11:48:00 PM

One thing you might try on the chrono is to screw some steel blunts into the arrows. I find it is much easier to get consistent readings.

That arrow should be right at 425 grains, maybe 10 grains more. Thats what my 30.25" 3555s weigh with 125 grains up front. At 9 gr/lb, I'm getting about 185 out of my homemade RD longbow, that's about 50# at almost 29. Would think you'd get better than 170. Good luck.

Blackhawk7204 · December 22, 2007, 07:18:00 AM

My 52# ACS-CX had to have a carbon express 350 (that's right a 350) heritage cut to 29" with nothing but a 125gr point up front. Chronoed in the high 190's. Anything weaker than that and it would not fly straight.
I have never shot any longbow or recurve in that weight that needed any stiffer than a 150 or a gold tip 35/55 before or since.

snag · December 22, 2007, 09:33:00 AM

Thanks for the info. guys. I think I will cut these 29.5" down to 29" and try it again. It can't be my draw length cause I checked that at 28".

Big Sneaky · December 22, 2007, 09:35:00 AM

What string silencers are you using?

snag · December 22, 2007, 12:18:00 PM

They are very light weight llama hair silencers. I really like them. They have made this bow very quiet w/out adding much weight to the string. I am going to put them on all my bows. This morning I went back to square one. I worked on the nock point and arrived at 7/8". I then cut down those shafts 1/4" at a time and went from 29.5" to 29". They were flying slightly weak with 125gr. I still can't figure out how some of you guys get the tip weight up to +200gr without them showing way weak. I think I can maybe go up to 150gr. with fletched arrows. I also worked on my grip and found one that the bow likes! That really changed the arrow flight instantly. Maybe because I have shot a recurve for so long this has been a hard change for me...? I seem to be learning...some are just slower learners than others. Thank you for all your help. I do appreciate it. Without you guys to sound off on and get ideas and recommendations from this would really be a lot harder.
With these changes I will chrono it again. I am going to go to a different archery shop and try their chrono machine to compare.

myshootinstinks · December 22, 2007, 03:21:00 PM

The ACS/CX experience I had was a little over 3 years ago, shortly after OL came out with the "CX" version. The bow I owned shot GTs okay but not the best arrow flight no matter how I weighted them. The best arrow flight came from a barrel tapered sitka spruce arrow. I got to rummaging around the shop and by golly I found one these arrows that I shot w/ the acs. This shaft is spined about 73#s, cut to 29.5" b.o.p., with a 125gr point. The weight is 566gr. The velocity wasn't quite as high with those arrows but arrow flight was about perfect, the best arrow flight I got out of that bow.
I have only one of these barrel tapered arrows left and have no real use for it. If you'd like to try it PM me your address and I'll throw it in a tube and mail it to you. Doug

snag · December 22, 2007, 04:15:00 PM

Thanks for the offer Doug. I have some 70-74# spruce shafts I will try.

I cut some off these GTs and got them down to 29". I also remembered that I had put some weight tubes and screw in weights in these arrows! Took them out and just put 125gr tips on and with setting up the bow I got much better arrow flight. I don't know their weight now. Probably around 420gr., which equates to a little more than 8gr per inch. The chrono with the lighter arrows was 185fps. Gained 15fps. But more importantly is the arrow flight and the consistancy!

kennym · December 22, 2007, 04:18:00 PM

I'd bet part of your speed gain was in the good flight! Glad ya got er goin right!

Precurve · December 22, 2007, 04:57:00 PM

I noticed several posts remarking their best flight from these bows came using wood shafts. Bob Burton of Whispering Wind Arrows talked about this awhile back, saying bows that are cut way past center have more arrow flight issues with the small diameter carbon shafts. Wondering if building out that arrow rest would give better results with the CX when shooting carbons? This would move the center of the carbon shaft out to the left, more closely matching how the wood shafts line up with the side plate in the original position.