You'll see some big numbers with hunter-friendly bows in due time, but not until we make better arrows.Two companies (High Country and Gold Tip) are already on the light arrow bandwagon. Others will joinsoon.

Look for ultra-stiff, 4-7 gpi arrows to be the real reason that we start seeing guys hunting in the high 300's. They'll have the best of both worlds - a user-friendly draw curve, a big brace height, and a smoking hot arrow. 1 pin to 40 with a little fudge factor. I'm already there.

Completely agree. The technological advance will be lighter stiffer arrows allowing the bow to not take the brunt of the damage.

Tom

IBO speeds of 400fps won't happen, just not possible. Like everyone else is saying more poundage or lighter arrows. I think advancements in building materials will allow you to safely do both in the future. I wouldn't be suprised in 10 years if every bow will guarantee their limbs down to 3 gpi. In the next 2 years most bows will be guaranteed to what HC is now.

To get an IBO speed higher than 400fps, you'll have to find a way to store more energy in the bow than you put in. Not possible.

Who cares? The deer won't die any faster. Aside from that, there's still such a thing as a point of diminishing return, a 400+ FPS bow would undoubtedly cost more than a 300, yet it wouldn't do the job any better. Same holds true for KE, once you have more than enough to penetrate any animal fully anything more is just expensive overkill. The bows we have today are already way more than anyone needs to take down game.

The X-Force is about the limit to "shootable bows" with its 6" BH and super aggressive cam.

Let's assume that we have a bow with the same draw force curve as a PSE X-Force. It has a 6 inch brace height and a very aggressive cam. This bow is IBO rated at 350 fps with a 350 grain arrow. That equates to 95 ft-lbs of KE. Let's assume that this bow is 85% efficient, which is about the best we can do today.

That means that you are losing 15% of the energy that you put into drawing the bow. The shooter needs to put in 112 ft lbs of energy into drawing the bow in order to get the 95 ft lbs of KE into the arrow, because we are only 85% efficient.

What happens if you increase efficiency? Even if this bow were somehow 100% efficient (which is impossible), you'd only get 380 fps with a 350 grain arrow (see the first chart). So we need lighter arrows.

Now, if you could invent limbs and arrows strong enough to shoot a 275 grain arrow out of the same bow, look what happens. Assuming we stay at 85% efficiency while shooting this 275 grain arrow, you would get 378 fps. The problem is you actually lose efficiency as arrows get lighter.

What if we got the same speed bow to 95% efficiencywhile still shooting a 275 grain arrow? You'd get 400 fps (see the chart).

So 400 fps IS possible. You just need a 6" BH, a super aggressive cam like the X-Force, super strong limbs capable of shooting a 275 grain arrow, a 275 grain arrow strong enough to be shot at 70 lbs, and a technological breakthrough that will push efficiency to 95% (we are not even close today). I think we've got a ways to go, but definitely possible in 10 years to see 400 fps out of the speed bows.

What is the theoretical "Speed Limit" for such a bow? Assuming a 70# 6" BH and an X-Force like draw force curve, if the bow were 100% efficient and shot a 200 grain arrow, you could actually get to 500 fps! That would give you 112 ft lbs of KE....

Here's the first chart - a PSE X-Force with a 350 grain arrow with efficiency varying up to 100%.

Here's what a PSE X Force would look like with 275 grain arrows and varying efficiency up to 100%.

There's a guy over at AT who is regularly shooting (and hunting with) a bow that's slinging arrows at 412 fps. 250 grain arrow, 31" draw, 70+ pounds.

I forget his name, but I talked to him a bit before I bought my bow.

The thing you have to consider is how many states will allow such a light arrow to be hunted with?

We'll all be able to acheive those speeds, but will we (lawfully) be able to hunt with them?

Another thing to consider is the KE acheived by the arrows. Yes, you'll be smokin' that arrow downrange, but will it hold its energy at 40 yards?

I call BS on that...I didn't miss any more when I was hunting with a 1975 vintage Bear Whitetail than I do now...Frankly, what I'm using now is 15 years old or so, it does just fine...Here in the woods in NC, you can't see past 30 yards in September and most shots are within 25....

Its about the setup, not the speed...