I just got my new Dobyns fury and I got the 7'3" instead of just 7'. Is there a difference or is it to just give you a little bit more backbone?

At first glance, I'd say about 3".

The power, which in this case is medium heavy for both rods, is the stiffness of the rod. The action, which in this case is fast for both rods, is how far down the rod the blank will flex under load before engaging the "backbone" of the rod. Fast action rods usually will flex in the first third of the rod before engaging the backbone. This can differ from brand to brand.

With all things being equal in your case, the only difference is length which will give you a little extra casting distance and a little more hookset power.

Longer length gives you extra casting distance and allows for quicker line pick up. With a longer rod you lose a bit of accuracy.

I love it ww2farmer. 

Same blank cut 2 different lengths.

Tom

What farmer said. bang on.

Distance for accuracy trade off.

3" will not gain or loose ya anything

But y'all have fun believing what y'all want!

3" will not gain or loose ya anything

But y'all have fun believing what y'all want!

 

that's not what she said.

 

*badum-tss*

 

If it is cut out of the same blank then the 7 3 would have a little more whip / softer tip. Which in same brands I believe would be the case.

3" will not gain or loose ya anything

But y'all have fun believing what y'all want!

Every inch counts, ask any woman

I suppose you don't know if there is a difference unless you have both rods.

Not a 3" difference but 6".  I have a med 7' & 7'6 as well as a med/hvy 7' & 7'6, those 4 rods are the same brand and model.  Do I think there is a difference............night and day.  Longer casts but the bigger difference is the backbone.  

I don't know these two rods but,  I often look at the handle length to determine what "real" length I am getting from the reel to the rod tip.

the 7'3" is actually .5 inch longer on the handle, the other 2.5 inch difference being in the rod.  like catt says, you won't notice much if any difference in a few inches.