What recoil can be expected through a sub 4" barrel?

I have a Glock 30 and recoil is not a big deal with it.I know nothing about the XD45 so I can't say for that.Also with my Glock 30 you can tell the recoil difference with some ammo but it is not a big deal.

The difference between a .45 ACP and a 9mm is quite a bit. 45 kicks pretty good, 9mm doesnt kick much at all.

I dont know much about the glock or the XD as they are polymer and Im an all steel kind of guy in high-power handguns. I use a berretta 92 most of the time.

I would say use something you can handle all the time, because if you are one-handing a .45 and drop it in a self defence situation, you probably won't be in good shape.

The recoil on a Baby Glock in 45 ACP may be considerable.

I traded a model 23 (Compact, not Baby 40 S&W) down to a model 19 (Compact 9mm) because that 40S&W in cold weather in that little plastic gun just tore up my lily-soft hands. My BIL (bro-in-law) loves his, though, so go figure.

As far as ammo and recoil, the configuration of the bullet (projectile) makes no difference, but the weight does! There is considerably less recoil in the 185gr compared to the 230 gr. Where I really noticed it was in the .357 Magnum loads. A 158gr bullet, with a magnum load, in JHP,SP, or any other point was brutal in my old Taurus model 66. The 110 gr was down right comfortable in comparison! Of course, a pair of Hogue or Pachmyer or Uncle Mike's soft rubber grips did a lot to tame that beast.

+P = Plus pressure, or added pressure over a standard load, which corresponds to higher velocity, and more energy to the bullet. +P's will, eventually wear out your gun. Standard loads will, eventually, wear out your gun.

When the +P craze started back in the early 90's Jon Liberal of Petersen Publications (Guns& Ammo, etc.) took a few of the aluminum-frame "Airweight" S&W .38 spec snub-nosed revolvers, and fired them to failure ('til they broke) with +P ammo. There were no catastrophic failures - no explosions, or any other failures that resulted in broken, or blown open metal. What did happen was that eventually, the cylinder and barrel would not line up (timing failure) and the firing pin no longer hit the primers. This occured after hundreds of (300-500) rounds.

So, does +P hurt your gun? Firing wears out your gun, but today's handguns can fire tens of thousands of standard loads with no problem. +P will shorten the life of the gun, but may save your life! So take standard loads (mil-spec, or police-spec) to the range, and, if you want, carry the +P's for protection.

In my above-mentioned Glock Model 19, I carry Cor-Bon +P 115 gr JHP. When I go to the range, I fire mil-spec 124 gr FMJ (jacketed round-nose).

I weigh 145lbs have small hands and the Kimber ultra carry 3" in 45acp is great. Very fast and accurate also easy to shoot and carry.