arrow question

the numbers you are referring to is the spine of the arrows. Greatly impacted by the DL and poundage set up...those figures will lead you to a preferred spine for your specific set up. Google the arrow manufacturer's spine chart and you'll see their recommendation.

Another influencing factor in arrow stablization in flight is FOC...higher the FOC the better in flight stabilization one should see. Think heavy tipped dart versus lighter plastic tipped dart.

I had shoulder surgery last winter and have my bow set at 60lbs and I use 100gr field points. So maybe the 350s are too stiff for my bow therefore maybe throwing my arrows off? I guess at this point I don't know if I wasted my money on the arrows or if it's something that can easily be fixed. Never would have thought it would have made too much of a difference

Post your bow model, exactly what model of arrows these are, your draw length and weight, and when I get home late this evening, I'll run it through my OnTarget2 software. Oh yeah, I'll also need to know what length the arrows are cut to now. Only the actual carbon length, do not include the nock or insert in that measurement.

M4...that would be great. Thank you!
Guess I still have a lot to learn. Once I get home, I'll get you all that Info and see what results you come up with.

OK I am shooting a bear encounter.
DL is 29
arrow is 28
set at 60 lbs
the new arrows are carbon express piledriver hunter spine is 350
I shoot thru a whisker biscuit rest and 3 string peep site with a D nock string loop

The first chart shows you being WAY stiff. Since your arrows have already been cut to length, the only way to fix the situation is to switch to 125-grain tips and increase the draw weight to 70 pounds. 67 pounds put you barely into the acceptable spine range. If the arrows had been cut to 31" or so, that would have worked at 60 pounds, as lengthening an arrow weakens the spine.

EDIT: The photos aren't showing full size on this page on my laptop, so if the page renders the same for you, you'll probably have difficulty reading the charts.

Yes. Heavier points, longer arrow shafts, and heavier draw weights all weaken spines.

My Bowtech Boss is 60#/28", and I use a .400 spine arrow with 100-grain broadheads.

I would have to disagree with the premise that the accuracy loss was due to the stiffer spined shafts.

I have always preferred shafts on the stiffer and heavier side than the ones shown on the charts. I like the durability of the stiffer shafts, their consistency when the release may be less than perfect under hunting conditions, and the effect of the added arrow wieght on penetration. IMO, the charts are heavily slanted in favor the "ideal" arrow for your setup being the one that yields the most speed without the loss of accuracy that DOES occur when the spine is TOO LIGHT. Going heavier than called for in spine stiffness has never caused a loss of accuracy for me during my 55 years of tuning and shooting year round, especially since progressing from the recurve to compounds with full centershot risers and carbon arrows.

My personal bows have shot very well when cranked down from 70# all the way to 29# when rehabbing a shoulder, and at every stage of recovery a few pounds at a time, with only a very slight adjustment in rest position to correct for the diminishing over-spined condition as I progressed.

Also, if you were having a problem with impact point being affected by too much spine stiffness, that effect should be consistent from arrow to arrow and not variable in direction or amount. The cause for a sudden enlarging of group size is almost certainly something other than stiffer shafts.

I suggest that your problem with longer range spread is more likely a form issue. It's very easy to let curiosity about the impact point with new arrows cause us to "peek" a little too quickly, causing accuracy to suffer as we unintentionally sacrifice follow-through to satisfy our curiosity about the impacts.

Other factors could have some influence, but most would be extremely unusual to find in quality arrows. If your fletching type, size, and orientation is the same between both groups of arrows, and your nocks fit the string pretty much the same way, I think a little more concentration on following through with good form after release will return your good group size. The group may be in a slightly different place, probably slightly lower and maybe an inch or two left if you're a right-handed archer, but should be at least as consistent and as small a group as with your previous arrows. The spine and weight change should have a small and predictable effect on the impact point, but the consistency and accuracy should be at least as good as before, and many guys have found them both to improve slightly with heavier and stiffer arrows.