bow equipment for buffalo

I read in some threads that the right bow equipment is a 80 to 90 # Bow with an 800 grain arrow. This can be right, but it must not be.
A friend me use an 5 years old bow with 90 # and an arrow with 800 grain. His draw length is 27".
I use an 70'# Destroyer. My draw length is 30" and the arrow weight is 777 grain.
The speed of my bow is 238 fps, my friends 215 fps.

What will I say:
not alone the # are important, look for the IBO speed of the bow. New bows have 330-360 IBO. Older bows only 290-310.
Look for your draw length Is big speed difference between 25" and 30"
1lbs dw is only 2.5ft., but 1" dl is 10ft.!
At last, forget the KE, it is only a physical formula.
For penetration use only the MOMEMTUM formula.

I respectfully have to disagree with your recommendation to use the IBO speed of the bow. We (my hunting partners, me and our archery pro shop) have done tests with many of the newer bows with extremely high IBO speeds that do not perform near the levels as my 4 year old Hoyt with cam and a half technology when it comes to heavier arrows. Age of the bow doesn't necessarily indicate performance. One of the key attributes to shooting a heavy arrow at higher speeds is the cams on the bow. Many of the newer bows with IBO speeds in the 320's and up are shooting one cam with only a roller on the other end. These bows are very efficient at throwing a light arrow at high speeds but they lose a lot of performance when you put a heavy arrow in front of it. IBO speeds are measured using only a 300 grain arrow, not a 800 + grain arrow. Last year my father shot a Cape Buffalo bull at 22 yards with an 83 # Hoyt at 26.5" draw length. He was shooting an 850 grain arrow with a two blade broadhead. The arrow penetrated the near side by clipping the edges of two ribs on the way in, took out both lungs and heart and got stuck in the opposing rib. The bull went down 50 yards later. But what we learned here is that set up would be a minimum recommendation due to the fact that the arrow was stopped by a rib. That particular bow's IBO speed was slower than many of the bows we tested but it would push the heavier arrow much faster than the competitors. I have tested my 4 year old Hoyt with similar technology against even the newest Matthews Z7 and my bow will out perform the Z7 with even 470 grain arrows which I use for plains game and North American game even though the Z7 has a much higher IBO speed.

I do agree with your Momentum formula but also do take into consideration the Kinetics.

Dr. Ashby did many tests over many years on Cape Buffalos and many other animals and concluded that E.F.O.C. is one of the most important attributes besides shooting the right bow. EFOC or "Extreme Forward Of Center" is crucial in momentum for penetrating such dense muscle and bone. I recommend looking up his studies and do lots of actual testing to help decide on the right archery tackle before hunting such a dangerous animal.

This is a very deep topic and I just want everyone to be aware that I have only begun to scratch the surface of the research that has been done and just wanted to bring some light to the subject.

Glad to see someone else is hunting the "Black Death" with stick and string. Much luck to you and happy hunting!

Here are a couple pictures of my father's buffalo with the arrow still in the rib.

Hi Stalkhunter

Your bow is fine, I would say if you can, turn the poundage up to about 75 lbs your arrow weight is fine.
Hope this helps

Dox

Quick correction... the draw length was a typo. He was actually shooting 27.5" draw. The Kinetic Energy of that setup was 83 ft/lbs.