Draw weight and arrow weight question

[kglacken]

I am going to turn my bow up to 70 pound draw weight. My draw length is 28 inches. I shoot 400 grain Beman ICS Hunter arrow with a G5 Montec 100 grain Broadhead. My question is, do I have enough strength in my arrows to shoot my bow at 70 pounds? I want to gain more speed, but stay accurate at the same time. Right now I am confident in my shooting out to 50 Yards but from 60 I get a little timid. I want to turn the bow up to 70 pounds from the 58 it is set at now to gain more speed and gain more confidence at 60 yards. Will 70 pound draw weight be ok with a 500 grain arrow set up?

[hughjorgan]

As long as you have the proper spines arrow for the poundage it should shoot for you as well as be more quiet with the heavier arrow. You will need a .340 spined arrow....

[kglacken]

As long as you have the proper spines arrow for the poundage it should shoot for you as well as be more quiet with the heavier arrow. You will need a .340 spined arrow....

Right now I have .400. That will be too weak? Only reason I am asking is because the arrows get expensive and i just bought a dozen last year that are still perfect

[BULLBLASTER]

.400 would be weak at 70 lb. Try just going up a couple lbs. And see how it does. Even 2lb difference is very noticeable in shooting fatigue. More draw weight will not make you anymore accurate at farther range though. You have plenty of power as is to kill elk at 60+ yards IMO.

[kglacken]

I understand that it will not make me shoot any more accurate. I guess I kind of worded that wrong  I just dont like having to hold as high and if there is a slight wind I feel like at 60 yards the conditions have to be absolutely perfect. I might just buy new arrows. Would swithching to a 125 broadhead play a role in the strength? 

[alwinearcher]

a 125 grain head would weaken the spine of the arrow..

[carpsniperg2]

  Yes go lighter to stiffen the spine up.

[jechicdr]

Speed of the bow also plays into the spine decision.  400 is likely too weak spined for 70 lb draw for any bow.  Some of the slower bows could probably use a 340, but faster bows would likely need a 300.  100 grain broadhead is probably too light at 70 lbs as well.  Probably need a 125 or 150 grain.  Couple of shooting programs out there can be used to hone in on estimate of spine required.  On Target from Pinwheel Software is the one I have and it has a database of most bows and factory settings that can be tweaked.  You can download the trial version for free and get the answer to your question.  If you plan on making any future adjustments, it will save money to actually buy it since you won't inadvertently buy that dozen 340's when you needed 300's. and would have had a better setup with 125 grain broadheads instead of the 100's.  The full program also has some simulations that allow you to "practice" shooting off the range (different distances-can see how much drop say from your 80 yard pin if target is actually 83 yards, wind, angles).  Can even print sight tapes and make adjustments based on data from the range if you have an adjustable one, or get pin spacing for multiple pin setups.  Cheap investment, but well worth it.  There's another program that other people will recommend also.  Don't think it makes much of a difference for the basic features.  Not sure if the other program has the simulations.

[Johnb317]

I shoot a beeman 340 with 100 gr slick trick.  Have had full pass through on elk with this setup.  68 lb with 28 inch draw.   Don't forget to hunt in wa you need 6 gr/lb. and with arrows getting lighter it's getting tricky.   At 70 lbs your total arrow weight will need to be 420 grains. (knock,fletching,and broad head).   So with a 10gpi arrow and 100 gr broad head I just make it. 

[xsf1]

jechicdr@yahoo.com

downloading that program thank you!!!! 

as for my input I shoot a bowtech sniper with beman 340 28" draw and I had some problems when it was at 72 lbs, I reduced pull weight to 64 lbs and it shoots a ton better, thinking about picking up the new easton injexion 330's and seeing if I can move it back up and still keep the arrows shooting straight. either way you really dont need the speed in my opinion just momentum (kinetic energy) there is a really good artical about how to achieve that here http://tradgang.com/ashby/Momentum%20Kinetic%20Energy%20and%20Arrow%20Penetration.htm
its worth the read

[yajsab]

And just to add to that, 70 is not going to make a lot of difference on speed. If it was me, I rather go heavier on the arrow and then practice shooting far. 60 yards is very far for me to take a shot.

[RadSav]

If you have a 60 yard pin you have a 60 yard pin   Your bow might be angled a degree or two more with a slow arrow but you should still be holding dead on.  I assume the phrase "I just dont like having to hold as high" was just  a reference to your arrows trajectory.  In reality the difference in height held with the same bow shooting 400 spine and 340 spine or 400 grains compared to 450 grains is extremely minute.  Much better to get yourself correctly spined than to worry about minute differences in arrow weight.

As far as the effect on wind at 60 yards - High profile 2" vanes compared to 4" will make one heck of a lot bigger difference than 50 or even 100 grains of arrow weight.  Plus with the Blazer type of vane your FOC percentage should improve which dramatically improves performance in wind.  However, 60 yards is a shot few make regularly in the field when conditions are perfect and their arrows are perfectly fitted to the bow.  While I would never condemn a well practiced archer for taking that shot it really should only be taken when environmental conditions and animal position is just right.  That would even go for 50 yard shots.  If wind is an issue your best bet would be to wait for a better opportunity.

I'd really like to find out what your actual arrow length is and the model of bow.  The guys previous are absolutely correct about .400 being too light for 70#.  At least assuming your bow was made sometime in the last 12 years.  We could really get you more precise information on correct arrow choices if we had a little more input. 

If the expense of a new dozen arrows ends up being an issue I'd recommend staying at a poundage better suited to the current arrow spine.  Then later when finances change or you find yourself needing another dozen then worry about matching for the additional weight.  If you have a real nice dozen you could even ask at the range or correctly on here if someone was interested in making a swap.  Carp could answer the best way to do that so you don't end up in the H-W doghouse

If you are worried about efficiency in taking elk with lower poundage just remember this - For around 30 years Dwight Schuh has been one of the top elk hunters in the country.  Heck, he's one of the best bowhunters period!  And last I checked he's been shooting 55#.  I'd drop 15# of draw weight in a heart beat to have his level of success.

Good luck.

[xsf1]

RadSav, I have a question for you.
You were talking about vaines making a big difference and I am a very technical shooter (I like to figure out the physics and stuff) so I am shooting blazers and I'm right at 290 fps shooting a 340 beman with a 100 grain montech. shoul I be shooting a different vains? I have read an article a while back but I didnt really trust it saying that a 4" vaine is what I want to be shooting.... so what is your take on it? is there any articles that talk about this?

[RadSav]

RadSav, I have a question for you.
You were talking about vaines making a big difference and I am a very technical shooter (I like to figure out the physics and stuff) so I am shooting blazers and I'm right at 290 fps shooting a 340 beman with a 100 grain montech. shoul I be shooting a different vains? I have read an article a while back but I didnt really trust it saying that a 4" vaine is what I want to be shooting.... so what is your take on it? is there any articles that talk about this?

Depends.  What length length is your arrow and are you shooting the ViBrake inserts in your 340's?

[kglacken]

I shoot a Rytera bullet-x set at 56 pounds