What are your thoughts on moving up to #80 draw weight bow?

Wouldn't do me any good. I'm to old to pull that much weight.

I'm maxed out on the limbs of a 70# elite bow with great accuracy... Not sure I would need much more speed. The doe I shot this year was hit (pass through) at 30 yards and not a deer moved until she scurried off... Quiet and fast enough for me.

What for? Today's bows are plenty fast for anything you want to do with them and over doing the draw weight can be ruinous on the shot of a life time.

I shoot 70 lbs and I am 50 years old. I have never had any problem killing anything (deer or hogs that is) with that poundage.

Maybe if you wanted to be able to take 60+ yard shots 80+ lbs would make sense. I just don't feel too comfortable shooting anything beyond 40 yards so I don't see the need for 80+ lbs draw weight (even if I could pull it back).

Shot 80 as a young man back in the 70's and that was with 30% letoff, no more. I'm shooting 60 now.

I am all about speed but unless you can maintain form and placement I don't see the point. Also it's one thing drawing on the range and another in a tree or tripod. I guess that should be the test, if you can make a smooth controlled draw and hold it in a less than perfect situation by all means.

There's no reason when if you shoot 40lbs and hit a bottle cap at 60 or 80lbs and a bottle cap at 10 max. No need for it.

What you trying to make up for by trying to go up that high in weight

No need for it. What would you be trying to accomplish by going that high? There are people every year that kill elk and bear with 50 pound recurves. Shot placement with a sharp broadhead is what its about.

80#'s today is like pulling 60#l's 15 years ago. They draw cycles today are much better then before. But the real kicker is the efficiency and use of stored energy in to days bows.

As always match your broad head to your ke.

Low KE.... Fixed two blade head

High KE.... Pick a head.

Not true. Your KE numbers are much different. There for penetration will be much different

The reason I would bump up to #80 is 1)Cuz I can... and 2)So that with large game such as elk I would have more margin of error if I didnt have a chance to range my shot. Also the same goes for competition shooting where I can use a 20 or 30 yard pin with more room for error on guessing the actual range with the pins being so close together

Your IBO is your IBO. So if you plan on using IBO weight arrows than your speed will be about the same. If you shoot heavy arrows like I do, then yes it will be faster with the same gr weight arrow. With a 70lb bow your IBO arrow will be 350gr. If you shoot an 80lb bow you have to shoot a heavier arrow with a weight of 400gr. but the bow is rated to an IBO speed with an IBO weight arrow. (DONT SHOOT AN ARROW UNDER IBO WEIGHT! IT WILL DAMAGE EQUIPMENT NOT TO MENTION IS DANGEROUS.) whatever model bow at whatever weight will shoot a matched IBO arrow at about the same speed. You will really only increasing your speed if your new bow has an IBO that is greater than your last or if you shoot the same gr weight arrow that is well above IBO. I am a heavy bow shooter myself ( I own an 85lb and an 81 lb bow) and I have found that the extra weight only really makes a difference in speed with arrows that are above 500 gr. I hope this made sense and I did not confuse anybody.

Partially true. KE really does not matter much. With that you have to take into account the efficiency of the arrow design and momentum it has.
But I agree with what BOBO said! If you cant hit anything cause muscle fatigue or cause your movement while trying to draw then it would be better to use a 40lb bow.

I used to shoot a Darton Viper that I shot maxed out at 83lbs. It was fast. After two shoulder reconstructions I'm going the opposite direction.

I meant that if you can hit a bottle cap at 60 yards with a 40lb bow then you can kill a deer in most bow hunting situations. But if cant at 10 yards with an 80lb bow then you should be shooting the lighter weight.

00possum,
Sorry I got the name blocks mixed up. I agree with you and what you said. I just put the wrong name.

OUTDOORSMAN, could you explain the KE doesn't matter please? I think I disagree but want to hear your reasoning.

A lot of people putting stock in IBO ratings for their bow, but I don't think you will ever reach it unless you follow the exact standards used to achieve the ratings for that particular bow.

http://www.archeryexchange.com/shopcontent.asp?type=amoibo

http://www.bghi.us/index.php?x=bowspeed

http://archeryreport.com/2011/03/estimate-bow-speed/

http://www.bowhuntingmag.com/2012/03/12/backyard-bow-speed-test-hoyt-carbon-element-and-prime-shift/

http://www.bowproshop.com/arrowspeed.html

CMC,
I am on my way to work so I am only going to touch on a little part of this. However I am going to include a link to just one of the several articles that cover this.

Basically what it amounts to is KE is a formula founded on speed. (This is why the industry uses it. It will produce big numbers as long as you shoot light fast arrows. The down side is it does not predict lethality.) but KE actually has no direction. KE therefore it might give you an Idea of how hard it will hit but does not predict penetration.

MOMENTUM has both amplitude (an ‘amount’ value) and a direction. Because any measurement of momentum has a specified direction it quantifies the net force acting in that single, straight line, direction. Momentum is, therefore, known as a linear function, and is a measurement of the force of forward movement of an object. Therefore has the ability to predict actual penetration.

I have to leave for work so I will discuss this further when I get back from work.
Please read the study posted below. It is a little dry in parts but is very informative and well worth your time.

Momentum, Kinetic Energy, and Arrow Penetration
(And What They Mean for the Bowhunter)
http://www.alaskabowhunting.com/Ashby-On-Momentum-Kinetic-Energy-Arrow-Penetration-W19.aspx
I am looking forward to discussing this further once you have read the study.

If you can shoot it well go for it. You will get added penetration on big animals like elk. It is a bit of overkill for a deer and it will add miles to your shoulders. The bow makes a huge difference to, 80# with a less efficient (slower) bow will not get the same speed improvements as a faster bow, just something else to keep in mind.

Just to touch on KE a little. What outdoorsman81 says has some truth to it. However, by bumping up to a faster bow and using heavier arrows will give you more force on impact which is KE.

Think of it this way...
If you have a small car traveling at 60mph and a semi traveling at 60mph then the speed is the same and the direction is the same. When they hit the semi will cause more damage due to the size and weight which calculates into kinetic energy when it is released on impact.

With that being said, acceleration is what builds KE. So the acceleration of the small car needs a small engine to get the speed up to 60mph (#60 being the small engine) and the semi needs a large engine to get the speed up to 60mph (#80 being the large engine).

So if I get a bow at #80 draw in order to shoot a 400 grain arrow 340fps It's only to get more impact and penetration than I would with #70 draw and a 300grain arrow at 340fps.

I agree to the accuracy.... But not on just because you can shot spots with a 40lb bow you will be to effectively take deer at 60yards.

KE is a big deal because it give you broadhead options..

Ya but you can change your potential penetration just by switching broad heads.

Good example would you use a big cut expandable with a 40lb bow...no but with a 70LB you would.

Lots a great 2blade and 3blade fixed heads that are famous for penetration

From Dr Ashby's article
"Given two arrows of equal momentum, but with one deriving a greater portion of its momentum from mass than the other, the heavier arrow will change velocity (decelerate) at a slower rate as it passes through the tissues. In other words, the heavier arrow will retain a higher percentage of its impact velocity at any given time period during its passage through the animal’s tissues, thus it also retains a higher momentum at any given point during the time required for the arrow to penetrate."

So two arrows with the same KE but arriving at that KE from different ways, one with more mass and one with more speed will likely not penetrate the same distance. I think my definition of KE was not right.