Picking a Barrel for your 1911
Today, we have a huge variety of quality aftermarket barrels available for the M1911 auto pistol. Barrels are available in a multitude of calibers and a variety of external configurations to suit many different purposes. Different calibers and different purposes of use can be tailored for optimal performance by choosing the right combination of features on the barrel.

Match Grade, G.I. profile, bushing barrel
Almost every barrel maker offers a product in this configuration. This is the standard barrel profile that came in your gun, but with oversize external dimensions to allow custom fitting to your slide & frame and with a finely finished bore with tightly held tolerances in the rifling. The chamber is usually bored short of full depth and is often on the small end of the tolerance range in diameter. This barrel uses an oversize O.D. / undersize I.D. match grade bushing that has to be fitted to both the slide and barrel. The original M1911 designed two-piece feed ramp is used in this configuration.

Everyone generally makes a good quality barrel in this version. The market leaders are Bar-Sto, Kart, KKM Precision, Nowlin, Schuemann, Storm Lake and Wilson. My personal preference and what I use in my personal pistols is the Kart Precision barrel. They are made from chrome-moly steel rather than stainless steel. I don't see that as a drawback, unless you live and work around saltwater and not much of a drawback then. I'm not an engineer, but I'm told that chrome-moly has some characteristics that make it a much stronger, more durable material than stainless. That said, I would happily install a barrel for you from any of the above named makers and feel comfortable that you'll be satisfied with the job.

One Piece Feed Ramps
This modification was originally popularized by Jim Clark as a way to make .38 Special wadcutter ammo (which was used in bullseye and PPC revolvers) feed in a 1911 auto. Ramped barrels were revived in the 1980's to allow IPSC competitors to fire .38 Super ammo loaded in excess of SAAMI specs, without as much risk of case wall rupture as a standard barrel has, when fired with over-loaded ammo. The "Ramped Barrel" allows the lower chamber walls to extend further to the rear, enabling support of the cartridges case walls for their full length. It is accomplished by leaving extra steel below the chamber area, behind the lower lugs to allow an extra long feed ramp to be part of the barrel. To install barrels with these ramps, a slot must be machined into the frame to accept the barrel's ramp that extends into the magazine well. Additional machining must be done to create a new stop surface for the barrel to unlock against. Once modified, the frame can only be used with a ramped barrel.

This feature is really only needed in a few situations and calibers. The ramped barrel is mandatory for the hot rodded .38 Super cartridge, loaded to make the major power factor used in USPSA/IPSC matches. It is also highly recommended for the .40 S&W caliber loaded for the same competitive purpose. It is not recommended for .45 ACP or .45 Super chambered guns. Ramped barrels are not needed for any of the other popular 1911 calibers: 10mm, 9x19, 9x23, etc., because these cartridges have inherently strong cases. They can be used for those calibers easily enough, when circumstances dictate. It's a bad idea in the .45 because the cartridge centerline sits much lower in the magazine than smaller caliber cartridges, causing the round to strike below the ramp.

Bull Barrels
Bull Barrels are manufactured with an extra large in diameter in the section forward of the top locking lugs. Due to the extra steel, these barrels are heavier than the normal G.I. profile barrels. The increased weight has the effect of reducing muzzle lift and softening felt recoil. The most prominent makers of bull barrels are Schuemann, KKM Precision, Nowlin, Ed Brown and Bar-Sto. The Bull Barrel does not use a barrel bushing, instead locking up directly with the slide. There is a theoretical advantage to the bull barrel being stronger and more accurate due to the extra wall thickness making the barrel stiffer, but in my opinion, it's a very slight advantage, if any. The more weight you can add to the front end of the gun, the less it will lift in recoil.

Coned barrels taper from slide diameter at the muzzle down to normal barrel diameter at the top locking lugs. I think bull barrels, which are of a constant diameter in the lower half, are a better design because they are better supported by the slide's interior bore, when the gun is out of battery. The fact that there is no barrel bushing to retain the recoil spring plug makes it necessary to use a reverse plug to retain the recoil spring. The reverse plug gets it name from the fact that it has to be installed from the rear end of the slide's spring tunnel, rather than the muzzle. The slide has to be modifies to allow use of the reverse plug.

Compensators and Ported Barrels
Compensators and barrels with porting vent and re-direct gas in an effort to minimize muzzle lift and felt recoil. They can be a serious advantage in the competitive arena, because they can help you shoot faster and more accurately. They have no business in the arena of self-defense, because the vented gas can cause serious injury if allowed to come into contact with the body.

Compensators work to reduce muzzle lift and felt recoil by utilizing the combustion gas volume and pressure drive the compensator to reduce felt recoil. The gas column that propels the bullet is redirected by a series of baffles and vents to provide forward thrust and vertical thrust to push the gun forward and down as the gases leave the compensator. Ported barrels simply expose an additional escape path to the column of gases, after the bullet passes by. If the volume and pressure of gas is great enough, muzzle lift may be reduced to some degree.

One drawback to both comps and ports is that they only work well with the higher-pressure cartridges. The .45 ACP doesn't develop enough pressure to make a compensator do much. The ports do make a larger flash signature possible than without any ports, in a most cases. If you have to shoot from a close-to-body retention position, you may be injured from the vented gases. Another side effect is that both comps and ports make the guns appreciably louder; a factor to be considered in close-in scenarios. My short answer is that compensators and ported barrels are really great in a competition environment and are a really bad idea for use in a self-defense environment.

Drop-in Barrels
Almost everyone in the barrel business makes some form of a drop-in barrel. They vary from one to another as to how readily they drop in and how work. When you consider the number of manufacturers in the 1911 market, all working to different tolerances and dimensions than the next guy, it's no wonder that the results obtained from drop-in barrels varies quite a bit.