VA5326

Someone asked me what the difference is between the two (85 & 100 grain) broadheads.I know the weight difference, but, if you have two of the same bowswith the same poundage set andall the variables are equal why would you want either a lighter (85) or heavier (100) broadhead. Would an 85 have more velocity and pass through easier or would it be vice versa for the 100. Sorry if this sounds trivialno one has ever asked me that question before and I felt like I couldn't give the man a straight answer the other day.

VA

Madjac20

The weight of the tip (broadhead or field tip) will affect FOC. I believe there is no one answer to cover every possible set-up. Take a look at the web sight below, don't know if it'll help, buttake a look atthe calculator in the Fletching & FOC chapter, it should help decide the bestweight for your arrow.
(http://www.huntersfriend.com/arrowhelp/arrow-selection.htm)

BGfisher

The 85 grainer will be a few fps faster, but not a lot. 5 fps max. For a hunting bow this won't show any difference. What is more important is how the arrow is spined and FOC. If the arrow is spined on the light side the lighter head may improve it's flight. But if the FOC get to be too low then that may allow the arrows to shoot well, but drift around because there isn't enough weight at the front.

The only real way to find out is to shoot them both, possibly tuning for each and see how they fly. If they appear to group well with both weight points then it's time to put on respectively weighted broadheads and see how these do.

It's most likely that with field points you won't be able to detect a difference at all.

Paul L Mohr

Most of the time a 85 grn head will also be a bit shorter in length and have a smaller cutting diameter. Not always though.

Also everything else mentioned above.

The smaller cutting daimeter may give you slightly better penitration if you have a lower powered set up. Probably not more than a heavier arrow and tip would though. In my opinion the added momentum from the weight would be better than the lower profile tip. I am also a big fan of higher FOC arrows.

Paul

Sylvan

The heavier arrow, though a touch slower,would carry more ke and momentum and theoretically therefore have a higher potential to penetrate. The difference is so small though it just isn't going to make a practical difference for a hunter. I think you'd be hard pressed to measure the difference even in a laboratory situation.

killzonearchery

well i think that the 100 will stablize it more then a 85. I think that 85 is to light and could throw your aroow off.

Justice4all

Ok, from a tuning standpoint. A lighter head will increase the spine of your arrow. While a heavier head will decrease the spine of your arrow.

Ok, for example. If you normally shoot a 70lb bow and have a properly spined arrow with a 100 gr head. Let's say you want todecrease the poundage of your bow to 65 lbs, but want to use the same arrows. the spinemight be too stiff to matchthe new weight of the bow. To correct this you could increase the weight of the head to a 125 gr.

But, on the other hand if you have a 60 lb bow and a properly spined arrow with a 100 gr headand want to increase the draw weight you might have to changethe spine to get correct flight. And to correct it you would have to add an 85 gr head to stiffen your arrow.

It is not about velocity or kinetic energy. It is about matching the right head to your set up.

archer58

This year I experimented w/ the same scenario you are asking about.
You'll see my set ups below. With the same arrows(Beman BlackMax 400s fletched w/ Blazer vanes) the difference was 3 fps.(269fps vs. 272fps)and a difference of 2% (10.1% and 12.1%)on FOC. I used 85 gr. Slick Tricks and 100 gr. Slick Tricks w/ 1/8in. difference in cutting dia. The heads hit w/i 1 inch of each other at 30 yards. So I would say for the sake of cutting dia. go w/ the larger head.
Otherwise it's personal preference.