Over spine an arrow?

[Johnb317]

A friend needed new arrows, and wanted to stay at 420 gr weight. Shooting old beman 34O 10gpi 27.5"  100gr point pulling 56 lbs.
It was suggested he go to 300 spine 28" (9.5gpi). Seems to shoot fine with field points. 
I shoot 28" 70# 340, should I be looking at 300's?

Does over spineing hose broad head tune?
What's the downside of over spine?

Thanks

[coachcw]

Rads the man here , but I have never had a issue being on the stiff side, my broad heads have tuned fine.

[rtspring]

Rads the man here , but I have never had a issue being on the stiff side, my broad heads have tuned fine.

That AINT what she said...

[dreamunelk]

How do they shoot?  That is the big question.  If they fly true with broadheads and arrows then things should be okay.   

[Johnb317]

He hasn't tested with a broadhead as yet.

I took one of his and put a broadhead on it and it flys about the same as my other broadheads on a 350 shaft. (low and left  )
Arrows have gone lighter - but if I stay at 70lbs I still need 420 gr. total weight.... maybe go to a 125 gr. broadhead / point.
I'm currently shooting Carbon Express - running low and would like to buy something made in the US.   the shop I use sells Beman.

Think I go through this every few years.... but this is the first time someone suggested going to a stiffer spine.

[demontang]

Over spine won't hurt anything if your bow is set up right. I'm shooting 28" ctoc  arrows that are 300 spine with zero issues at 60lbs. The 300 spine will be more gpi then 340 and you can put more weight up front to hit your 420grns and not worry about getting under spine.

[theleo]

Like it's been said, being a little over won't hurt. I try to keep where the manufacturer suggests though. Depending on the arrow length you prefer you could shoot a 300 spine and be pretty close to on the money for correct spine especially if you end up shooting 125 grain heads. I'm shooting 300 spine BEA arrows with 125 grain heads and they've been flying great for me. I'm pulling 74lb with a 28.5" draw and my arrows are 27.75" long (throat of the nock to the end of the insert).