Head Diameter of Starline .45 Colt brass?

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Does anyone have some Starline brass they can mike for head diameter, please?

I have Winchester brass which gives a bulge ahead of the case head in my ~1978 Ruger blackhawk. At first I thought it was the chamber but the brass at the bulge mikes .482 and the case head of my Winchester brass mikes .476...indicating the brass is undersized. (I think Win must use the same tooling for .45 ACP & Colt?)

.45 Colt spec is .480 so my chamber does not appear to be the real problem.
 
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I have 200 pcs of starline brass bought in 2021 that I've never loaded. They have been sized but other than that, unused. I pulled 10 pcs from the container and they all measured 0.477 at the base.
 
Mine measure .4755 with the calipers resting on the top edge of the rim.
 
Thanks very much, Guys. That is very interesting.

I was thinking about getting Starline but if it's no different than the Win, not gonna.

This is curious tho, as going thru many reloading books they all have Colt listed as .480.

The sizing die does not appear to get below the bulge so maybe brass life won't be a problem. Weird thing is I've had .45 Colts (Smith & Ruger) in the past and do not remember such a problem.
 
And.....for giggles, I have a box of Fiocchi .45 colt that I bought before I started reloading that caliber.. They are currently fully complete rounds that I reloaded. Brass is on the maybe 5th reload. measured 0.477 at the base.
 
Thanks. Even Fiocchi.

Curious, do you guys get bulged brass from your .45 Colts?
 
Thanks very much, Guys. That is very interesting.

I was thinking about getting Starline but if it's no different than the Win, not gonna.

This is curious tho, as going thru many reloading books they all have Colt listed as .480.

The sizing die does not appear to get below the bulge so maybe brass life won't be a problem. Weird thing is I've had .45 Colts (Smith & Ruger) in the past and do not remember such a problem.

What problem are you having? There may be some info out there from when 45 Colt was a standard .454" bullet. In modern times, it has become a .451" just like the 45 Automatic. You shouldn't run into any issues with brass life or anything. I've never run into that issue, although I usually load 45 Colt lower pressure with smokeless, or black powder. My cases last almost indefinitely.
 
What problem are you having? There may be some info out there from when 45 Colt was a standard .454" bullet. In modern times, it has become a .451" just like the 45 Automatic. You shouldn't run into any issues with brass life or anything. I've never run into that issue, although I usually load 45 Colt lower pressure with smokeless, or black powder. My cases last almost indefinitely.

Just a recurring bulge accountable for by the disparity in dimensions of the chamber and fired case that has a base (in front of the extractor groove) of .476. I've had a number of .45 Colts in the past and d not ever remember this situation. With a case fired miking .482 the chamber can't be too far out of spec. This is a new gun to me.
 
SAAMI Specification for the .45 Colt chamber is .4862" to .490.2" What is your question? Do you know what your chamber diameters at the base are? If your fired cases are .482 there is no issue. Any bulge left ahead of the solid portion of the cartridge case is a sizing matter, usually because that portion of the case cannot be sized because the shell holder prevents the case being sized clear to the rim, and none do and it isn't really a bulge, just an un-sized area.

Are you having a problem, or is your question merely about the cosmetics of the "Bulge"? From the dimensions you give everything is completely normal. There will always be a small area in front of the case rim that will be larger than a factory new cartridge case that has been fired then re-sized! This happens with all calibers!
 
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SAAMI CHAMBER spec is .4862" +.004".

So the Winchester (& apparently Starline) stuff is w/in spec on the low side (.476) and my chamber may actually be slightly undersize per SAAMI but still gives a spread of some .007" or maybe possibly a smidge more if case springback is actually greater than .001" as I have not done a chamber cast, just measuring the fired cases.

So it is a cosmetic issue of sorts, but a technical one I've not seen w/ a number of .45 Colts in the past. The gun is new to me. Not a big deal, just curious as to it's existence.

And yes, I call it a bulge generically.
 
I was going to add to my post that with only 19 total posts, and the nature of your question, that you are quite new to reloading, aren't you? But you beat me to it with your second.

From your last, the answer is NO. SAAMI Specification for .45 Colt cartridge base diameter is .480" minus .006". Your cases are not at minimum, but rather nearler the SAAMI maximum. The Winchester that you have measured are at the maximum of the diameter tolerance. As long as any brand of unfired brass is between .474" and .480" they are within SAAMI specification tolerance. As long as your chambers are between .4862" and .4902" they are within tolerance. Quit worrying about something that is not a problem!

In this case you can expect as-fired case diameter can measure from .474" to .490", or .016" Your .007" is quite low.

All things mechanical have tolerances, as long your items are within specified tolerances there is no problem. This includes reloading dies too. If your ammunition goes into your gun after being fired, sized and reloaded everything is good, quit worrying about how it looks, all reloads have cosmetic issues when compared too closely to factory new ammunition!


I have no idea what you are expecting!
 
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Your oroblem may be more symptomatic of the issue with modern .45 Colt sizing dies, in particular carbide.
Midern carbide dies for .45 cal pistol most often use the same generic carbide ring insert for .45 Colt and .45 ACP. Heck, the special .455 Webley dies offered by Lee is simply the same die they sell for .45 ACP but with a different rollmark.
The older steel sizing dies offer true full length resizing. Furthermore, they size the brass to spec, that being the gentle taper for the full length of the case.

See attached diagram
 

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I was going to add to my post that with only 19 total posts, and the nature of your question, that you are quite new to reloading, aren't you? But you beat me to it with your second.

From your last, the answer is NO. SAAMI Specification for .45 Colt cartridge base diameter is .476" minus .006". Your cases are not at minimum, but rather nearler the SAAMI maximum. The Winchester that you have measured are at the maximum of the diameter tolerance. As long as any brand of unfired brass is between .474" and .480" they are within SAAMI specification tolerance. As long as your chambers are between .4862" and .4902" they are within tolerance. Quit worrying about something that is not a problem!

All things mechanical have tolerances, as long your items are within specified tolerances there is no problem. This includes reloading dies too. If your ammunition goes into your gun after being fired, sized and reloaded everything is good, quit worrying about how it looks, all reloads have cosmetic issues when compared too closely to factory new ammunition!


SAAMI CARTRIDGE spec is actually .480" -.006" which puts the cases in spec but on the low side at .476" as I noted.

SAAMI CHAMBER spec is .4862" + .004".

You can find the data here:

"SAAMI Z299.3 – 2022 – Voluntary Industry Performance Standards for Pressure and Velocity of Centerfire Pistol and Revolver Ammunition for the Use of Commercial Manufacturers, page 50."

SAAMI Standards - SAAMI

I never said I was "worrying" about anything and I am not. I'm just interested in the details of my hobby and work.

As for your other questions, I've been handloading since about 1977, for a large number of calibers. I've used my handloads in various calibers all over the USA and in Africa where I lived for a time in the late '80's. I rarely shoot factory ammo in rifle, shotgun or pistol.

I joined the site many years ago and was well-known for years here, lost my account and the Moderators very graciously gave me my old handle when I restarted an account.

This little case detail came to mind due to the fact that I have owned and handloaded for several .45 Colt revolvers (Smiths & Rugers) and never noticed anything similar on the case. I pay pretty close attention to those things and anything out of the ordinary sparks my curiosity.
 

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