1911 Caliber Conversion

Im looking to replace the barrel in my Colt 1911 government, it shoots fine now, but id really like to pull the accuracy outta this handgun, but after seeing what new barrels cost, i was wondering if I should figure on just converting it to a new caliber. What do ya'll know of convertin the .45 acp to 10mm? or other calibers.
The limiting factor is the breechface in the slide. Your .45 slide is set up for a .45acp case size, and won't work with anything smaller. You could use a .400 corbon, which is a necked-down .45 case. You would need to fit a new barrel and bushing, of course. And get .400 Corbon ammo, which is a disappearing wildcat cartridge.

Changing to a .38 Super, 9mm, .40, or 10mm would all require buying a new barrel, slide, slide stop, ejector, and magazines.

The cheapest thing to do "for accuracy" is get a knowledgable gunsmith to fit a new bushing (if your barrel is OK), or a slide/barrel combo if your barrel is worn out (that takes A LOT of hardball shooting to do that).

Good luck.
By "accuracy" I assume you are shooting off hand. Just about any "mainstream" handgun will be capable of a 3 inch group fired from rest (by an experienced shooter) at 25 yards. A highly tuned match grade pistol might put all shots in a 1 to 1.5 inch group at 25 yards. In comparison, a typical shooter is hard pressed to keep all shots in 6 inches at 25 yards off hand.

Often, the best way to tune a 1911 is to have a gunsmith improve the trigger bringing the pull to 3.5 pounds (for target shooting) or 4 to 4.5 pounds if the gun is for defense (these days many 1911s are around 7 pounds trigger pull out of the box) and to replace the sights if they are those tiny mill spec sights.

If you are an advanced, highly skilled bullseye shooter-getting a match grade barrel and bushing (which will need to be hand fitted) would be useful....but for the typical shooter overkill.


Another factor in accuracy is quality ammo - good handloads can cut a gun's group in half. It's not that factory ammo is bad but can vary in consistency and with prices and availability right now it may be hard to find the best ammo for your gun. Also most handloaders load reduced velocities for accuracy and ease on the gun. If you know somebody who reloads maybe you can try some of their 'pet' loads and see if it makes a difference before changing out parts only to find nothing has changed . My most accurate load? 4 grains of Bullseye and a 200 grain Laser-Cast SWC. Turned a 4" group (from factory hard ball) lightly tuned 1911-A1 into a sub - 2" group at 25 yards "casually" rested. Also let someone else shoot it to see if anything changes.
you've gotten some good advise so far. unless the barrel is "shot out" or is otherwise damaged the gun can still be tuned for the accuracy you're looking for. the single most contributing factor in 1911 accuracy is consistency. if the barrel locks to the slide the same every time and the slide locks to the frame the same every time, the gun will shoot great.

the least expensive way to do this is the barrel bushing, and frame/slide fit. have a reputable 'smith fit them. if you like it you're done, if not move on to the next item the bottom lugs. they can be welded up and refit. then the trigger. then the sights. then if its still not workin for you, you can have a barrel fit and all the other accuracy enhancing stuff is already done, rather than haveing to pay for a new barrel and finding out it still needs other work done.


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