Hello, So I've been shooting long enough to know I've got a good tune with 175gr. field points. Now before I buy broad heads I've read that they could stand to be a little lighter since they are longer than field tips. I guess my question is just how much less , if I get some the same weight will it make the shaft to weak. Or am I just over thinking it. I'm leaning towards the 160eskimo or 170no mercy both from zwicky. Have a great Saturday.

Sounds like a "wheelie" thing.  Actually, I've never found any issue with a properly tuned set up going from a field point to a broadhead of equal weight on the same set up.

I'm shooting the exact same weight field tip and broadhead.

I think you should try the same weight broadhead and shoot it.  I have never seen an issue like you describe.  I am not the best with abstract notions, but I still don't see how a head that is longer (within reason) but the same weight makes any difference at all in spine.
ChuckC

Thanks for the answers guys . I really wondered if this question was worth posting. I think I really ought to sleep at night instead of surfin the net. Have a great day.

You may find that buying a 170 grain broadhead doesn't mean you will end up with 170 grains after getting it hunting sharp.

When you get them mounted shoot a couple. Some BH's fly differently than field points.

L.

My 175 gr field points fly the same as my 175 gr ace blunts which fly the same as my 175 gr Simmons Tiger Sharks....

Good Luck

Rodd