100grain to 75 grainbroadhead

[New2Bowhunt]

i went from 100 grain broadheads to 75 grains and they shoot much better through my bow, getting tighter groups but what is the average increase in speed for this 25gr difference?

Thanks

[Grunter]

don't worry about the speed... worry about what you're shooting! That's a pretty lightweight broadhead for hunting big game!

[Mikey]

.... That's a pretty lightweight broadhead for hunting big game!

I would have to dissagree with that statement .....My arrows (with 100 grain BH) weigh in at 426 grains ...If I were to drop to a 75 grain BH it would drop my total to 401 grains.... at 426 my bow pumps out at 276fps making about 72 pounds of Kinetic energy at about 65# draw weight. with 401 grains the KE drops to about 71.5 pounds of KE with my speed increase I would see of about 6fps

you would gain some speed and yer KE loss would be negligible if you are using a modern compound bow that has alot of speed to begin with ..... 50 or so footpounds of KE is plenty to take down any big Game we see in North America.

If your grouping better and hitting what yer aiming at then you have found a better suited combination of arrows and BH than you had ...All I gots to say is Congrats buddy

Mikey

[New2Bowhunt]

Well the speed isn't really a factor for me but the tighter groups sure had me excited!! my season starts next weekend and im itchin to get out hunting!

thanks guys

[Grunter]

I would have to dissagree with that statement .....

Awesome! Thanks Mike, you're the first one to ever set the issue straight for me on the mechanics and performance of a broadhead and arrow. I've always been told to never have less than 100gr broadhead, 400gr arrow or 60lb. draw for hunting elk and moose which is where my primary interests lie for big game hunting. I guess that isn't necessarily the case.

After the season I will definitely look into a lighter broadhead and see if it affects my accuracy and confidence the way it has for New2Bowhunt!

[Mikey]

No problem ... I was told that same thing as well when I got into Archery .... after thinking about that statement for a good long while and rolling some numbers around .....with todays Modern bows that average around 300FPS IBO rating ......as opposed to yester-years bows that averaged say 250 IBO .... I could see needing 100 grain or bettern to get the KE needed for a good clean kill ....not anymore however, Granted I was using my bow an example thats IBO rated at 330 ... a pretty snotty bow all things considerd ....


as long as the numbers are there for good KE and the mechanics are there for good penitration(ie: good BH design and sharp blades etc...) all is good

[Captainkip]

So does that mean that New2Bowhunt will also change his field tips to 75 grain? Does the broad head always have to be matched to the field tips that you use to practice with?

[Grunter]

It would only make sense to be using the same weight field tips otherwise your sight adjustments would drive an archer nutty!

[Mikey]

So does that mean that New2Bowhunt will also change his field tips to 75 grain? Does the broad head always have to be matched to the field tips that you use to practice with?
I sure would ......like Grunter says ...it would drive me nuts .....

that being said the arrows I use for target are not the ones I use for hunting ..... I shoot all year round..but its only in august do I switch over to my hunting set up untill I fill my tags then I swap it all back to get ready for indoor target season .... Change of rest , change of sight and a differant stab ... I keep draw the same. my target arrows are 339 grains while my hunting arrows are 426.

[russ]

Mikey, you're far more ambitious than me. All I do is remove the nibbs from my ACC's, put in some inserts & add 85 grain points & BH adapters. I also switch to a 4 pin tru-glo on my sure-loc. Who says 3D equipment can't be the same as deer hunting ;)

On the penetration (Kinetic Energy) issue - I'm setting up an old Darton Impulse & MKII cams for bird game and found it necessary to use 2514's so that the arrow would extend past the front of the riser. So for giggles yesterday I took the bow and shot some 418 grain 2312 target arrows I have through the chrono and got 283 fps & 73 ft. lbs. - then I took my 32 1/2" 2514's weighing @ 567 grains and got 237 fps & about 71 ft. lbs KE. In the past I've found that 2 cam bows seem to produce more raw KE with lighter than heavier arrows and that 1 cam bows do the exact opposite. My tests were limited to only 2 or 3 bows so the validity of my observations are certainly questionable, but at the very least, are cause for some more thought.

[New2Bowhunt]

I have already purchased the 75 gr field points and although they dont hit "exactly" the same (about 2" to right) they still group well and i am gaining confidence with my new setup like i have never before!

Thanks for the awesome tips guys.

[BOHNTR]

Russ, that mid-90s Impulse was an extremely aggressive bow even by todays standards. Close to a 5" BH, hard hatchet cams with less than 60% LO. I remember that bow kicked like a mule too.
Speed of a bow is mainly attributed to the length of the power stoke ( the distance you actually pull the bow back) If you have two bows with the same cam or cams, and draw length, say 30" One has a 5" BH and the other has a 7", the shorter BH would be quicker. Early single cam bows were lemons but with the evolution of single cams, Hybrid cams and the new Binary cams, the twin cam has been equaled or for that matter surpassed.

Here is my setup: Allegance 60# 30" draw 28.25" actual, 7" bh, GTs 400 ultralights with 100 grain Muzzys that weigh a total of 381grains, 295-296fps about 72 ft/lbs. feild pionts and broadheads group the size of a coffee cup at 60yards.

Can't wait to put them through some venison.

Good hunting
Allan

[russ]

Actually Allan the BH on the Impulse is 6 1/4-6 1/2" other than that you're pretty much right on the mark. I think the PSE G Force had a sub 6" brace height and not too many people could should it that well.

[BOHNTR]

I am going to measure the BH on the Impulse that is in a freinds locker. Oh the Baby G was 5", had one these were some of the bows that gave short ATA bows a bad name. Also make people think that the short ATA bows now have the same greif. Not so at all.

Best regards
Allan