Diameter of 45 ACP Lead bullets - .451 or .452?

[Huskerguy]

Call me confused. I just started to cast my own 45 bullets with a Lyman mold, 220 grain round nose bullet, single lube groove. I have both the .451 and .452 sizers so I am OK either way on this. Most, if not all of the lead bullets I have seen commercially are .452.

Then I read in my Lyman book, page 380, "Groove diameters can vary from .450" to .453" but the shooter should not size cast bullets larger than .451" due to chamber dimensions."

I want to limit the potential to leading and understood that with lead, an extra .001 was ideal. So before I prep several hundred of these, what is the correct answer?

 

[ReloaderFred]

I size all of my .45 acp and .45 Colt bullets to .452". No leading, and excellent accuracy.

Hope this helps.

Fred

 

[rcmodel]

+1

Unless you have a gun with a very tight chamber, you want to size .452".

As a test, load an unsized bullet in an empty case and see if it will pass the 'Plunk Test' in your barrel.

Of it will?
You can see where this is going.

rc

 

[Lj1941]

Undersize in 45

Back early in my lead bullet career I unknowingly bought a box of 500 185 grain LSWCs. I shot them in a WW2 M1911A1. It was a disaster. I finally looked on the box and they were .451. I realized my mistake and learned a lesson. Leading was terrible and accuracy was horrible. Lesson learned the hard way.:banghead:

 

[pretzelxx]

I depends on your barrel, usually .0015 larger than the bore is best, but you can size over to .002

You might try a group of 5 in both and after the shots, check for leading. That would be your ideal diameter. Then work up for accuracy and ballistic needs

 

[heycods]

slug your bore to be sure, slugged my Rugger 45 LC and was shocked to see .449, next step is new calipers!

 

[rcmodel]

Don't be concerned about a revolvers bore size.

Be concerned about the cylinders chamber throat size.

That's what a lead bullet must be sized to fit if you don't want leading problems.

rc

 

[Rico567]

Depends on the gun. The only way to be sure is to slug the bore. When I bought a Bar-Sto barrel for my 1911 many years ago, it came in tight- .451. So I just got a bullet sizing die in that diameter, no problems. Jacketed didn't seem to matter.....

 

[USSR]

Huskerguy,

First, do not assume that your sizing die will size to the proper size. I sized my bullets using my .452" sizer, loaded up some cartridges and had chambering problems. Measured my bullets and they were .453". So, bought a .451" sizer which end up producing .452" bullets (at least they're consistent). Your chamber will be what tells you what size bullet your handgun will accept. If the barrel dimensions are 1 or 2 thousand less, no matter, the bullets will accept that just fine.

Don

 

[243winxb]

45 acp fired in an auto. Revolver may be different.

.452" in normal for lead. The diameter of the cast bullet as it drops from the mould may be more important. Sizing down more than .003" may hurt accuracy. Slug your barrel, size to that diameter or a hair bigger if that is what the sizing die gives you.

 

[greyling22]

you want them as big as will fit in the chamber. I load for one 1911 that takes a .452, and another one that takes a .454. as usual, follow RC's instructions: try a couple as cast, then start thinking about sizing if they don't fit.

 

[243winxb]

As cast diameters & reliable chambering-45acp autos

The problem with "as cast" is the alloy. Different alloy = Different diameters. This is why its best to size the bullet, if you want reliable chambering

Bullet Sizes & Weights – How to Vary Them - The bullet diameters and weights presented in this list
are based on the use of Taracorp’s Lawrence Magnum
bullet alloy (2% tin, 6% antimony, 1/4% arsenic,
91.75% lead).
Bullet diameters and weights will vary considerably
depending on the lead casting alloy used. This variation
can be as much as 1/2% on the diameter, and 8% on
the weight among the most commonly used casting
alloys. For example, a .358-158 grain bullet might
show a diameter variation of .002", and a 13 grain difference
in weight.
Of the most commonly used alloys, wheel weights (.5%
tin, 4% antimony, 95% lead) will produce bullets having
the smallest diameter and heaviest weight, with
such bullets running approximately .3% smaller in
diameter and 3% heavier than bullets cast with
Taracorp's metal. Linotype will produce bullets with the
largest diameter and lightest weights. This alloy will
produce bullets approximately 1/10% larger and 3%
lighter than Taracorp. Other alloys of tin and antimony,
with antimony content above 5%, will produce bullets
with diameters and weights falling between those cast
from wheel weights and linotype.
Alloys containing little or no antimony will cast considerably
smaller than wheel weights and in some cases
will produce bullets too small for adequate sizing.
Within the limitations given above, the weight and
diameter of a cast bullet can be adjusted by varying the
alloy’s antimony content.
The size and weight of bullets of a given alloy will also
vary according to casting temperature. Higher temperatures
will result in greater shrinkage as the bullet
cools, thereby producing a slightly smaller and lighter
bullet than one cast of the same alloy at a lower temperature

 

[USSR]

you want them as big as will fit in the chamber.

+1.

Don

 

[Huskerguy]

Range report

What I am still not certain of is the comment in the Lyman book. Never did get an answer on that one.

I did check the .452 and they were actually .453. So I sized some with the .451 and they were "around? .452.

I went with the .452, 1.270 OAL, 5.0 grains of W231 and they shot well and everything cycled. Ran ten rounds down the range and the barrel is clean as a whistle.

Now I will load a few more and start to get my load set but from what I see right now, there isn't much to mess with. thanks for the help guys.

 

[243winxb]

Lyman, depends on who wrote the book and when. There website FAQ has this.

: How do I determine the proper sizing die for my particular gun?
A: We recommend slugging the barrel. Select a sizing die that is .001" over your groove diameter.

http://www.lymanproducts.com/lyman/faqs/bullet-casting.php

 

[RealGun]

It doesn't do any good to custom size bullets, if the dies and case tension just swage them down anyway. .45 ACP is very much a .451 jacketed and .452 lead proposition and possibly some custom dies to make the best of the lead.