45 cal .451 vs. 45 cal .452 bullets

I am trying to find some bullets for my 45ACP but I'm not sure which one is suitable for my 45's. Can anyone tell me which one would be better for use in an automatic?
Thanks.

.451 for the acp and .452 for the Colt HTH

Bud,
Thanks. I found a couple boxes of jhp .451 and grabbed them. Now to find some primers and powder!!!!!

?????
Been reloading for 40+ years . With that , .451 was the jacketed bullet diam. and .452 was the lead bullet diam. of all modern .45s after WW2 or so. The old Colts from the turn of the last century used .454 lead bullets .
Has something "new" come along ?
Chris

Spec for the prototype 45 ACP bullets ran anywhere from .450 to .452". The official diameter of the M1911 was .450 - .451".

As an old time 45 shooter, let me ask you this. Do you really think it makes any difference? There are not many shooters who can shoot the M1911 well enough to know which diameter would be best. If you really think you'd be able to tell, why not slug your barrel to see what it actually measures, and then go from there. Or, do as I used to do, buy the bullets that are readily available and cheap.

JMHO

Ray

Thanks all. Like I said, I tracked down a couple boxes of the .451 jhp so I have enough to reload the cases I have just to make sure my stores are up to capacity. With the prices and lack of ammo and supplies today I guess I won't be doing my quarterly qualifications even though I don't have to anymore since I'm retired.
Thanks again.

.451 vs .452 may not make that much difference, but bullet style and purpose do with regard to pressure, performance and function. I suspect that duke133 is experiencing what many of us are, shortage of bullets available desiged for .45 ACP, but bullets designed for Colt .45 and Casul etc are available. Lots of 300 gr bullets out there. If you found some boxes of bullets suitable for .45 ACP, you're doing pretty good in this climate.