Im looking to buy a Springfield XD in .40 in either the 4" service model or the 5" tactical. They are both the same price at the shop I will be getting them at. Wll the extra inch make any worthwhile difference in performance? How much velocity should the longer barrel generate, if any? Will 1 inch help that much with accuracy due to longer sight picture

Thanks for any help in advance

T dheifference in barrel length/sight radius will be less than the natural variation between any two handguns...wouldn't be too surprised to find some of the shorter versions outshoot the longer ones.

Same reason I hate to guess at the vel. difference. IF both barrels were idential in internal dimentions and chambering, and concidering the cartidge, then the longer one would be about 6-9% faster.

Intention of use would be a good guide...is it to become a concealment gun?

The 4" vs 5" debat is the biggest crock of brown stinky bovine gravy that's come down the pike. Hey, 90% of your self-defense shooting occurr at 20 ft. or less. What's the big deal?

I got to agree with Walter and ribbonstone both. If you are going to conceal it get the short barrel, otherwise get the one that feels better in your hand. I have a S&W 4013 tactical with a 3.5 inch barrel it shoots like a house afire and I don't see the short sight radius as a problem. I find I shoot my Ruger Redhawk a lot more simply because I don't have to chase the brass all over.

If you take an action with a long barrel and chrono the results from very accurately & uniformly loaded cartridges and then start lopping off the barrel an inch at a time, you will find that muzzle velocity drops off in a curve that is logarithmic (OK, I just lost a lot of you, I know). This experiment has been done & published several times over the years. Now throw in the variation due to different chamber dimensions, bore dimensions, load differences, and in the case of revolvers cylinder gap and you have a lots of variation not caused by barrel length. Probably best to find a gun that does what you need it to do comfortably and then go to work finding the load you want, else you'll drive yourself nuts.