Sizing cast bullets to .452 or .451 for .45acp..?

[Marcus the Cat]

Looks like I'm going to have to buy a damn lubrisizer after all..!!!

I started seating bullets today and a few were actually crushing one side of the cases. Even the ones that did seat, bulged out the case so much that it wouldn't even come close to chambering correctly.

It looks like some of my casts are measuring out as much as .456 and my barrel is a perfect .450 so I am thinking that I might go with .451 instead of .452 that my mold is designed to throw. Does anyone have negative experience with sizing down to .451 instead of .452 like my mold is "supposed" to throw..?

[Bkid]

You slugged your barrel and measured .450,is that correct? If so then .451 should be perfect.

[Marcus the Cat]

You slugged your barrel and measured .450,is that correct? If so then .451 should be perfect.

No I haven't slugged my barrel, I actually don't even know what that means. What I did was put the digital calipers to it and it measured a perfect .450.

When I consider that both my FMJ and Golden Sabers caliper at around .446, I figure sizing down to .451 can't be too small.

[Bkid]

No I haven't slugged my barrel, I actually don't even know what that means. What I did was put the digital calipers to it and it measured a perfect .450.

When I consider that both my FMJ and Golden Sabers caliper at around .446, I figure sizing down to .451 can't be too small.

Well my 1911`s all seem to have a .451 barrels. I size all my 45 acp bullets to .452 and they work like that for me. I am not sure what you barrel is as far as measurment. Slugging a barrel is usually done with a pure lead ball,it is pushed through the barrel. If you are using a 1911 most likely it is a .451. I would try some .452 bullets and just see how they shoot for you if you are shooting a 1911.

[Marcus the Cat]

No, I am shooting either a Taurus PT 145 compact or a PT 845 full size.

As I said in post #3, I have measured the inner diameter of my barrel with digital calipers and it was right at .450 on the nose.

Thanks for your advice..!

[miestro_jerry]

I would check your measurement again, I just "miked" my Hornady bullets and several others, they come in at .451, which is what is labeled on the boxes. My cast bullets are sized to .452, and are to that spec.

Then I checked some of those copper washed/plated type of swaged bullets and they are .451

Your FMJ and Sabers coming in at .446 seems to be wrong. For all of my 45 ACP cast bullets, I make them .452, never had any problem with that diameter. Difference between .451 and ..452 isn't that much, maybe some accuracy issues, possibly leading, but either of those sizes should work.

I do suggest going with a Star Luber Sizer, it is a lifetime invest that will probably out last you and your grandkids.

Jerry

[Bkid]

I am not sure about measuring the inside with a caliper . I do think some .452 bullets would do just fine however. I shoot them in my Taurus PT 145 without any issues.

[Marcus the Cat]

I would check your measurement again, I just "miked" my Hornady bullets and several others, they come in a .451, which is what is labeled on the boxes. My cast bullets are sized to .452, and are to that spec.

Then I checked some of those copper washed/plated type of swaged bullets and they are .451

Your FMJ and Sabers coming in at .446 seems to be wrong. For all of my 45 ACP cast bullets, I make them .452, never had any problem with that diameter. Difference between .451 and ..452 isn't that much, maybe some accuracy issues, possibly leading, but either of those sizes should work.

I do suggest going with a Star Luber Sizer, it is a lifetime invest that will probably out last you and your grandkids.

Jerry

I know what you mean about .446 being odd, but I'm a tell'n ya' those suckers are pretty narrow. As a matter of fact I noticed the small size after seating them in my barrel and taking a look at it. They are obviously undersized just from observation with the naked eye. From what I understand, the bullet is designed to expand at the base when fired and fill the barrel.

But yeah, I put the calipers to them again tonight to check for this post and they both measure out at .446 on the nose.

[Marcus the Cat]

Thanks for the advice guys, I am going to place an order with Midway tonight..!

[Bkid]

Thanks for the advice guys, I am going to place an order with Midway tonight..!

Marcus,what kind of mold are you useing? I know this sounds like a dumb question,are you getting good fill out in your castings. I would think it is the mold though. Sometimes molds do not throw what there suppose to. You have options. You could send the mold back. You can make the cavities larger by using lapping compound. I am sure you know all of this anyways. Just tring to help out.lol

[Marcus the Cat]

I am using a Lee mold and was told to expect this.

But I measured a few of my casts and they measured right at .452 at the time. So either time has changed them somehow (2 weeks) or I must have really been squeezing those handles on the ones I measured back then.

When I checked the diameter right after casting and had .452's I thought maybe I could get away with not using a sizer, but apparently I'm going to have to buck up and shell out the cash, which I just did with Midway about 2 minutes ago..!

[Marcus the Cat]

Oh and thanks again..!

[miestro_jerry]

What alloy are you using? When you are loading your ammo are you using a taper crimp die or a Lee factory profile die.

If your factory bullets are .446 they would rattle out of your barrel from being so different from the bore and most likley have no accuracy.

In my casting with Lee molds, I see no real difference after water quenching them and a week or so later when I am sizing them. I have found a little bounce back after sizing some bullets, in short they come out of the sizer just a touch bigger than the sizer die. That is why I keep a variety of sizer dies on hand for doing bullets. For the 45 ACP, I have .451, .452 and .453. So far never needed the .453, but if I get an old 1911 with a shot out barrel the .453 may be needed. I have on my want list a .450 dies, but so far have never come across the need for that size.

I keep a larger set of mics and calipers onhand, my digital ones are for quick checks on things, the rest are the old fashion traditional measuring tools that I use in my machine shop.

Jerry

[mike in co]

where on the golden saber did you measure ?


they are a two dia bullet...the nose/fron half is small and the back half is stepped to full dia.

all golden sabers are made this way...a small driving band in the back rather than full length contact.

as an example..my 180/40 cal are .400 on the base and only .396 on the nose. there is a very clear step where the change occurs.

[sagacious]

No I haven't slugged my barrel, I actually don't even know what that means. What I did was put the digital calipers to it and it measured a perfect .450.

When I consider that both my FMJ and Golden Sabers caliper at around .446, I figure sizing down to .451 can't be too small.

Measuring the muzzle diam is what you did. This is not a true measurement of bore diam. If it was that simple, all the old hands wouldn't be wasting time hammering lead slugs down their barrels. You may wish to actually slug the barrel.

Re ammo measurement: Sounds like you're measuring the protruding bullets in loaded ammo. As stated, the GS bullets have two diameters. Measuring loaded ammo won't usually give a meaningful measurement. Good luck.

[Texasflyboy]

It looks like some of my casts are measuring out as much as .456 and my barrel is a perfect .450 so I am thinking that I might go with .451 instead of .452 that my mold is designed to throw. Does anyone have negative experience with sizing down to .451 instead of .452 like my mold is "supposed" to throw..?

What matters most is the size of the fired projectile. If you can load up a few rounds each with an incrementally sized larger bullet, and capture them in a water trap, you will quickly find which size is best for your barrel and your alloy.

I would load a few rounds with a .451", .452" and a .453" and shoot and recover the bullets in water and then measure those bullets. Observe which size has the best engraving and least amount of "skidding". Odds are the best engraved smallest size will be your most accurate for that barrel and alloy.

What I do with my 1911's is to load a few lead bullets at different sizes. I shoot them into a 55 gallon drum filled with water while standing on the top of a six foot ladder. I cut a 12" center of the barrel out with a sawz-all and cover the opening with saran wrap held in place with duct tape. I stand on the ladder and fire down through the saran wrap into the water. I recover the rounds and then measure the lands and grooves. Very easy to spot which size engages the rifling best.

FWIW.

[DLCTEX]

You could just buy a Lee sizer die and do fine. But if you need an excuse to buy a Lubrsizer, this one is good enough. I size all our 45 ACP boolits .452 and they work well in all our guns Tarus, Ruger, S&W, Auto Ord., Springfield).

[David2011]

Hi Marcus,

Something that jumped out at me was that your brass is bulging from your boolits. Boolits at .456" are too big. Compare the dimensions of your loaded rounds to the drawings in your reloading manuals. The max OD at the mouth of a loaded round should be no more than .473”. I use a straight tapered crimp die rather than a roll crimp because the case headspaces on the mouth.

One of the great things about the .45ACP is that it is old but very well refined technology that all of the manufacturers know. A .45ACP barrel that's a perfect .450" would not be perfect. It’s unlikely that your gun varies much from standard specs. Like others have said, you need to slug the barrel. Pour a few boolits using only stick-on wheelweight or another essentially pure, dead soft lead. With a brass rod drive a boolit though the barrel. I've slugged with a boolit in my usual relatively hard alloy. About 1/2" into the riflings I was wishing I had taken the time to make some soft lead slugs. Measure the major diameter across the raised area that was in the lands of the barrel. --Or you could capture fired rounds in a barrel of water like Texasflyboy does. You want to size .001 to .002 larger than that dimension. That will give the best accuracy and least leading.

Measure the expander in your reloading dies. It should be .002- .003" under the diameter of the projectile as determined by slugging for proper bullet retention.

I have had some military cases bulge if the boolit was seated too deeply. The military .45 brass I have begins to taper in thickness at the cannalure. I would expect any brass to bulge with .456" boolits in it, though. I run all of my handgun boolits through a Star lubrisizer. If you plan on shooting a lot they are the only way to go. It's easy to lube and size 900-1000 in an hour. I still have a Lyman 450 for gas checks and rifle where volume of production is less of an issue. If you find by slugging that your barrel is over or under the standard size you can get a custom die from Star or from Lathesmith who is active on this site. Lathesmith makes standard size dies at a good price, too. I’ll order from him next time I need one.

David

[Walstr]

Slugging 45ACP: I just verified my Kimber by loading a 185gr Lead SWC in front of 1gr Bullseye [it was available, but 1gr of any smokeless will do], fired & the "slug" was 3/4 down the barrel. [I use 2gr for slugging rifles with lead boolits.]

My mic reported .452"-.4525" for a groove diameter. My 185gr Lead SWC are listed & do measure .452".

Question: What & how much powder have y'all been using with these typical 1:20" pistol barrels & 185gr Lead SWC's?

I'm using 4.8gr Bullseye for my 200gr, Cu Clad SWC; averaging 736fps; a pleasant target load. Thanks.

[ReloaderFred]

You woke up a 5 year old thread...........

I don't shoot 185 gr. bullets in my .45 acp's, but I shoot a boatload of 200 gr. RNFP through them. I bump mine up to an even 5.0 grains of Bullseye for those loads.

Hope this helps.

Fred