This has certainly been asked before, so pls bear with me.

I shoot an AR 34 (2003, Ram Cam). The botom limb (with the sticker that tells the serial #, draw weight, etc.) says that you should shoot a minimum 420 grain arrow. My arrows w/o the crest (and with feathers instead of vanes) are 378 grains and my arrows with crests and vanes (instead of feathers) are 410. Both seem to shoot great for me. What gives?

BTW, I'm shooting PSE Carbon Force Extremes 400's (28") with 100 grain field tips/Muzzy 3-blades.

Also, what is an acceptable tolerance in weight for arrows? Mine seem to be +/- 5 grains or so.

Thx for the help.

some bow manufacturers like PSE/Archery Research
Require arrows to weigh 6 grains per pound of draw weight so if your bows peak drawweight is 70 they want you to shoot a 429 grain arrow

most other companys require to shoot at least 5 grains per pound

only 2 companys will warrant their bow to shoot less than 5 grains per pound, High Country Archery and Archery Pro LLC.

IMO shooting a 378 grain arrow will not hurt the bow I think that grain requirement is a little overkill on AR's part.

a plus minus 5 grains is acceptable number
you will get a plus minus of every componert you put on the shaft
any one who builds their own arrows need to invest in a grain scale to get their arrows weighing as close together as possible.

As BPS made reference to, that 420 grain recommendation is if the bow is set at its peak draw weight of 70 lbs....70 x 6 = 420 grains. However, it should also be noted that this recommended weight is also with a 30 inch draw length in mind. If your draw length is less than 30 inches then you can get away with less than 6 grains per pound of arrow weight....going by AMO/ATA recommendations.

To make it really easy...if you are shooting the bow at 65 lbs with a 28 inch draw length then a 378 grain arrow would be nothing to worry about.

Use this calculator to find the minimum AMO arrow weight for your setup:

http://home.att.net/~sajackson/amochart.html

Hope this helps. Be safe.
Shoot Straight
Derbytown

I own a jeweler's scale that measures in grains. When I referenced the +/- 5 grains per arrow, I was referring to the actual dispersion between my completed hunting arrows (407 to 412) . Is that 5 grains of dispersion good, bad, or indifferent?

Incidentally, I've sent a note to AR. I'll post their response to my question regarding minimum arrow weight if/when it's received.

JMO, but I never shoot below 6 grains per lb and never will!
I believe, even though manufacturers warrant for 5 grs per lb it is still too low.
Most bow manufacturers never did want to warrant for under 6 grs per lb.
They do only because they finally gave in to pressure from those first manufacturers who began to warrant for the 5 gr. limit.
My current arrows for my Bowman and Merlin bows are 6.7 to over 7 grs per lb.
You almost never hear of limb problems with heavier arrows like you do with 5 grs. per lb and below.
Anytime I read a post about someone's limb exploding or cracking, I can't help wondering they probably shoot 5 grs or less.


Sag.

ufg8r93,

That 5 grain range isn't bad and won't make a noticable difference at short hunting distances. You wouldn't want to have that range if you were shooting 80+ yards in field archery, but the amount of difference in impact point at 20-30 yards is negligible in a hunting situation.

Sag, makes me wonder how they'll respond to the Speed pro arrows HCA/Newberry bows...

I agree and would further add that many shafts are listed as having as much as as a +/- 5 grain difference from one shaft to the next.