Increased poundage limbs - change arrows yes or no?

4d4m

Active member
Hi I've had my bow for a year now and want to get some heavier limbs now. The general advice is you'll need to change arrows, but to what degree is it necessary for a difference of one group or so?

Here is my current setup:
70" bow
SF Forged+ riser
SF Elite fibreglass/foam limbs (long) 30# @28", wound up to within 1 turn of max.
Draw 33" (to rest + 1")
On the fingers poundage is 41

From my reading of the charts that puts me at top end of T10 or bottom end of T11 (extrapolating)
My ACEs are 430 so are in T10 for recurve. The arrows are full shaft length with 120gn piles, just under 34" from nock to tip.

I was thinking of upgrading to 36 lb long limbs starting with the bolts fully wound out, so would estimate about 44-45 on the fingers which is top end of T11.

To me it does not seem to much of a jump in terms of arrow spine, but what effect would that difference have in the real world? I could trim 0.5" off them fairly safely, and also reduce the pile weight a bit as they are the ACE break-off points. These arrows cost me a lot more money than I wanted to spend at the time (ACCs were too short in stock length meaning not much margin) and I don't want to have to replace them just yet if necessary.
 

frustratatosk

New member
Personally I would try them as if they were good before then they may come out a bit weak but quite possibly not (especially if you can shorten a little as that will have a marked effect on the dynamic spine)

P.s. My draw length has shortened considerably as it got better, moved to higher poundage and opened my stance a little. At first I think I was drawing as far as possible.
33 inch is a long draw! (and difficult to pick arrows for) Mine has gone from 30.5 down to 29. Check again with your new limbs, arms compress!
 

4d4m

Active member
.
33 inch is a long draw! (and difficult to pick arrows for) Mine has gone from 30.5 down to 29. Check again with your new limbs, arms compress!
Thanks, yes it makes things complicated and usually, more expensive. Good point about the arms compressing. As long as I'm not lifting the shoulder too much.
 

Rik

Supporter
Supporter
If you do try fiddling with the arrows, don't bother with altering the point weight. You can't take off enough weight to make a difference on that scale.
 

backinblack

Active member
Suck it and see at first...

As Rik says, you won't achieve much by reducing point weight by itself but adding weight to the back of the arrow has a greater effect than to the front so you could try pin nocks and heavier fletchings to see what difference that makes and maybe combine with smaller point weights.

Finger in the air, the increase in poundage that you are talking about (4lbs or so) is a whole spine which equates to a difference of 1 inch in shaft length so I'd suggest that you will probably need to do more than fiddle with point weights etc and that trimming by half an inch might not be sufficient (though in combination?). A further option, however, is to take the half inch off the back rather than the front as this has a greater stiffening effect on barrelled arrows and you may be able to keep a better FOC.

There are a number of threads that have discussed this in relation to X10s and ACEs so you could check out what you might expect in real terms, though obviously this is a paper exercise at the moment and what you get in real life may well differ from the theory.

Best,
Backinblack
 

4d4m

Active member
Thanks Backinblack. My next question if trimming arrows would have been where to trim front or back.
 

JohnK

Well-known member
Wow. Someone with a significantly longer draw length than me. Don't see that every day :D

You've had some good advice here so far, but on another subject, I'd like to advise you to seriously consider changing to a 72in bow if your budget allows.

I shot 70in bows for years, and the string angle was just too sharp, causing me to hunch up and reduce my draw. I now shoot 72in bows, with a draw length approaching 32 1/2in (to the back to the bow).

Just my 2p. Good shooting!
 

4d4m

Active member
Thanks. So that would be a 27" riser? Not intending to upgrade that for quite a while. I can't say I've noticed any issues with string pinch. I also have a 68" flat bow but not noticed much issue with that either.
 
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