300 or 340 spine?
Contributors to this thread:Equipment
From: Dmott
19-Nov-20
Some help would be appreciated. I'm new with regards to learning spine, weight, etc. For 150gr broadhead should I use 300 or 340 spine? My current arrows measure 31in and my DW is 53lbs. I heard with longer arrows you need a stiffer spine for heavier broadheads. On easton spine chart it says add 6 lbs for 150gr. I guess they mean if I want it to hit like my current 100gr do? I'm pretty comfortable pulling 53 lbs. Guess I would just have to sight in the 150gr? Also, any suggestions on arrows to go with the 150 gr broadheads? Any help is appreciated. Thanks
From: skookumjt
19-Nov-20
Increasing the point weight from your current 100 grains to 150 grains decreases the arrow spine so the chart tells you to add 6# on the poundage to compensate. Follow the chart and you have the answer to your own question.
From: Bou'bound
19-Nov-20
It’s tough to go wrong by being too stiff to bless shooting recurve or longbow
From: pav
19-Nov-20
^^^This^^^
From: midwest
19-Nov-20
^^^^That's what she said.
From: Will
19-Nov-20
I'm sorry, but Viagra humor on Bowsite is always a winner :) !!! You guys are hilarious!
OP - Sookum nailed it.
From: Old Reb
19-Nov-20
I'd have to look at the chart to be sure but I think you add 6 lbs to the calculated bow weight not your actual bow draw weight. You would leave your bow set at 53 lbs. Correct me if I'm wrong.
From: 12yards
19-Nov-20
Do you need 31" arrows? I shoot 150 grain heads on 340s out of my Elite Synergy at 29.5" draw length. But I cut them to 28". If you could shorten your 340s, I think you'd be good to go.
From: wyobullshooter
19-Nov-20
Old Reb, you are correct. You don’t actually change the bow’s draw weight. And yes, what Bou posted is 100% correct. It’s darn near impossible to have too stiff of a spine when shooting a compound and release.
Charts are just a guide. As an example, I shoot 26 1/4” shafts with 125gr tips @ 57lbs. Every chart in the world says I should be shooting 400 spine. My 340’s shoot like darts.
From: Dmott
19-Nov-20
I checked the easton spine chart again and it says add 6lbs to your bow weight if changing from 100gr to 150gr. Sounds like they are saying to bump up your poundage (if you want your arrows to hit the same as your 100gr and you don't want to sight your bow in again). If I'm seeing this wrong please correct me. If the chart recommends 300 or 340 spine for dw being 53 and arrow length 31 which spine would you suggest for 125 or 150gr BH? Thanks
From: greg simon
19-Nov-20
If you are going to buy new arrows get the 300's. The six pounds you are adding is only on paper. Add it to your actual draw weight to use in selecting spine. 53+6=59 Don't change your draw weight on your bow. Use 59 pounds for arrow selection.
From: wyobullshooter
19-Nov-20
Dmott, you need to understand the difference between actual bow weight and calculated bow weight. As has been stated several times, you only bump up the 6lbs on the chart selection bow weight, NOT on your actual bow. The chart has absolutely nothing to do with sighting or resighting in your bow. As for the point weight, it’s strictly personal preference and what tunes best out of your bow.
From: Dmott
19-Nov-20
Understand now. Thanks
From: WVFarrier
19-Nov-20
31" seems awful long. Ive got monkey arms and still only use. 28"
From: APauls
19-Nov-20
If you were to increase your draw weight another 6# you that means you need a stiffer spine yet...
There are a number of ways to play with spine. Adding weight up front, adding draw weight make you need a stiffer spine. Decreasing draw weight, or tip weight, cutting down an arrow or even adding weight to the rear of the arrow like wraps can have the same effect as stiffening the spine. As mentioned above. Maybe you've got extra shaft length you can zip off and be good to go.
From: Dmott
19-Nov-20
Yeah when I got my bow a few years back I went to my local archery shop and the guy said I was lucky I had a 31" draw length. My current arrows actually measure slightly over 31. Like 31 2/8. Most people have told me you want your arrow long enough so the broadhead just slightly sticks out further than your hand so you don't get cut which makes sense.
