In tring to figure out what weight broad head to shoot I was just wondering what the difference between 75 grain and 100 grain is. I u know 25 grain but in terms of speed, are they much slower? I just shot through a crono graph with the 75 gr and I was 260 ft/sec. I cant get back down to shoot 100s till the end of next week. Any predictions/estimations of how much slower the 100s will be? Also in terms of trajectory, I will the 100s drop quicker?

I am shooting 64#
28.5" GT XTHunters

Any advice would be helpful.

The speed lose is only going to be a few fps.

The main difference is going to be in arrow spine the heavier head will weaken the spine.
So check to see if you are boarder line with the 75's I would not reccomend the 100's.
On the other hand if you are way over on spine with the 75's go with the 100's.

I would be boarder line if I went with the 55-75 that is why I bought the 75-95. I can afford to go up if I need to. I just want the flattest shooting arrow/weight that will group with field points and broadheads. Thats why I started out with the 75 grs. I figured they would fly flatter and the smaller broadhead would fly more like field points.

Also what about trajectory? Right now I am one pin 15-25 and I like that.

Since you're using 7595's, I'd go ahead and bump up to 125's to really bump up your FOC, for better stability, plus making the arrows spine out good deal better. 28.5" 7595's are way stiff for a 64 pound bow. Don't worry about your trajectory. I seriously doubt you'll see any difference.

I am going to have to agree with Arthur on this one.You are a little stiff to begin with and the 125 grain heads will help.The biggest gain will be with bringing your foc to about 11 % with the 125's and that is absolutely perfect.This is assuming you are using 4" vanes.If you are using feathers,then the 100's should give you acceptable foc.Going with 125's will only cost you about 12-15 fps and I promise you will not notice the speed difference but you will probably notice tighter groups and a much easier time of tuning broadheads.

Field points are cheap enough to buy a 1/2 dozen of each and start group tuning with each.Remember if the heavy points are shooting a little low to go ahead and move the sight slightly and then start checking how much the drop is between your 15 and 25 yard shots.( I doubt you will see a difference at 25 yards with your sight settings)You will not notice a difference of ANY signifigance in drop and I believe grouping will be better.Remeber that if you decide to go with fixed heads you will see much more problems than with the field points.But this will give you a start.

I would seriously consider the 125g head for your arrows. We can get together and play with the diffrent weight heads and the numbers and see what works best for your set up. Once we get the speed for each head we can figure out the ke and which head gives you the most ke while still maintaining good speed.

If given the choice between a 100g, 115g, or 125g head I would choose either the 100g or the 125g head as there are more choices for broadheads in those weights but that's something that can be discussed once we have some numbers to work with.