# .45 Colt vs. .45 ACP bullets



## Revolver

What are the difference between the bullets used for .45 Colt and .45 ACP? Aren't they the same diameter? Can a specific cast bullet be used interchangeably? Excuse my ignorance as I've never loaded for these two cartridges.


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## Bob Wright

*.45 Bullets*

Older Colt revolvers in .45 Colt had bore diameters of .454" while .45 ACP had a bore diameter of .451". Of late both use .451" diameter.

To answer your question, .45 ACP bullets can be used in .45 Colt cartridges. The heavier cast lead SWC bullets intended for the .45 Colt usually do not work too well in ACP cartridges.

I have loaded the 230 gr Hornady jacketed Flat Point bullet in the .45 Colt and in .45 S & W cartridges to good results.

Bob Wright


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## Revolver

I knew I could count on you for the answer. The .45 Colt in question would be modern. A Ruger DA or SA, or a S&W 625.

Now I know it's only bullet profile I need to worry about for reliable feeding in an automatic. Thanks.


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## Bob Wright

*.45 Colt & .45 ACP Bullets*

One other bit of information: Bullets for the .45 ACP do not have a crimping cannelure, and if loaded in .45 Colt cases, no attempt to crimp should be made. Trying to crimp on these bullets turns the case mouth out and relaxes the neck tension on the bullet, resulting in errattic performance.

When I was using a lot of different bullets, I had two seating dies for .45 Colt, one set to crimp, the other no crimp.

Bob Wright


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## spacedoggy

I too was getting confused when ordering bullets. I asked my son once again on what size to order for 454 casull. He yelled at me and told me to look up the specs of each bullets in my reloading manual. The 454 and 45 acp are the same .452 and the colt is .454. Now my question is can you use a .454 with a .452 load? It's so close. What's the general rule??


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## Bob Wright

*Bullets*

As most new guns in .45 Colt have bore diameters running .452", they are interchangable. Cast bullets are often sold as .454", which is o.k. as they swage down when fired.

I did get some bulk bullets, 185 gr. jacketed wadcutters, that ran .450" and did not shoot worth a hoot.

I have used Hornady and Sierra jacketed bullets of .452" in my .45 Colt guns and they provided me with excellent results. Just remember not to try to crimp these bullets when used in .45 Colt cases.

The question will arise, I'm sure, as to why I used these bullets. The Hornady bullet was a 230gr. flat point full metal jacket, the Sierra was a 185 gr. jacketed hollow cavity, both of which I wanted to try at the time. The 185 gr Sierra was especially destructive at around 1300 fps.

Bob Wright


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