I shoot Beeman MFX Classic arrow out of a longbow. Because of my short draw length (27 inches) I have to leave the arrows at their full length (31 inches) in order to get bare shafts to fly strait.

I recently read that shorter arrows are more stable.

Am I sacrificing anything by having 4 inches of arrow hanging out in front of my bow?

Don't believe everything you read. Shoot arrows that are tuned well to your bow and let that decide length. I shoot plenty of arrows longer than 31" myself for the opposite reason of you.

If your arrows are flying well and they happen to be a couple of inches long,don't worry about it. Flying well is flying well no matter what. I shoot full length wood and carbons with my 29" draw,theres 1/2-2" sticking out front..so what they fly good.

You are sacrificing nothing with long arrows. If you have some over hang that just means you don't have to shoot as far.  

With carbons I do worry about length,I let the tuning of them determine the final length.They don't come in as many different spines as wood or aluminum.I draw 27" and my carbons depending on the bow are from 29" to 31.5" long.If they are flying good I wouldn't worry about the length of carbons.

I agree there is no inherent problems, but if you need that length to weaken the spine, why not just shorten them and add wt. to the front end?  Even more wt. f.o.c could be a great advantage.  And, with all things equal, a shorter arrow should be more stable.  I would shorten and add wt. just for experiment- you may really like what you get.

Leave them long, once cut their cut. If your like me you may decide later you want to try a different BH/wt. I usually regret cutting..not the other way around.

lots of good points and counterpoints listed here about his dilema. I am with KSdan as far as cutting them some and adding weight to get them to barshaft tune for him. Just be aware that carbons respond to length much more than adding or subtracting weight. Seems like you have to make a 100 gr weight change to get them to react, yet a mere 1/4" in length will stiffen them dramatically !!! Once you get close to the correct length you gotta be careful and trim a little and shoot several times to make sure you are getting the correct bareshaft reading. Gotta make sure you have a clean consistent release to read the bareshaft correctly.

And as champ38 said..... "Once they are cut, they are cut "    

nocams

I've build and shot selfbows for the last 20 years.Recurves and longbows 10 before that.So with selfbows you have to be a little more closer to the correct spine and leanth helps with that.
 So I start with 31 inchs and move back by cutting a 1/2 off to your bow desides the correct leanth.If it's not to short it dosn't matter.

Short arrows more stable?? Seems it should be just the opposite to me assuming they are correctly spined. Kinda like throwing a spear(not that I throw a lot of spears    ) Take a long spear and throw it, then cut it in half and throw it again. Alot easier to get good flight from the longer projectile.

Obviously this is not a scientific study, just common sense talking.

Don;t believe that short arrows are the way to go ,,I draw 26" and shoot arrows at least 30" I think arrows fly better  long than short also if you bamage the end you can cut it off and use it as a stumping or beat around arrow just add more tip weight

I was one of those that never wanted an arrow over an inch longer than my draw.One day in order to tune the shafts I had on hand for a certain bow they needed to be 2" longer than what I normally shot.My shooting improved in the first few days and I started cutting all my arrows that length.A few weeks ago after watching some freinds shooting full length shafts I decided to try some.At first I did not really care for the long arrow.I decided to give them a chance and shot them for a week.My shooting improved again.Those few left and rights that you don't know where comes from went away.You are never to old to try new things and learn that your way my not always be the best way no matter how long you have done it.  :D  I don't worry about long arrows any more.

psedude. . . not debating as I am not the guru of arrow spine/tuning. . .but I have a 32" draw- and wind sure seems to affect 33+" arrows far more than others I see who shoot shorter shafts. I also gave up on wood shafts at that length as the spine always seemed to weaken after shooting them for awhile.  

I would sure experiment with the shorter shafts and more wt. up front.