45ACP Short Cases

Bucksnort1 · February 3, 2021, 03:19 PM

I am resizing 45ACP cases. I use a case gauge to periodically check for proper fit. I have two cases, one by S&B and the other a Federal that are not flush with the top of the gauge. They are below about 1/16".

Head space on semi-autos is determined by the mouth of the cartridge touching a ridge in the chamber. Both cases measure .884" - should be .898". These are at least once fired cases which I picked up at a range.

I will toss these two but out of curiosity, is there a danger in loading and shooting them?

74A95 · February 3, 2021, 03:36 PM

No. No danger.

Old_School · February 3, 2021, 05:52 PM

Quote:

Originally Posted by Bucksnort1

I am resizing 45ACP cases. I use a case gauge to periodically check for proper fit. I have two cases, one by S&B and the other a Federal that are not flush with the top of the gauge. They are below about 1/16".

Head space on semi-autos is determined by the mouth of the cartridge touching a ridge in the chamber. Both cases measure .884" - should be .898". These are at least once fired cases which I picked up at a range.

I will toss these two but out of curiosity, is there a danger in loading and shooting them?

Not that uncommon. And although it won't result in best accuracy, it won't hurt anything.

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RC20 · February 3, 2021, 06:52 PM

Make sure they are not 45 GAP (shorter glock case)

**Unclenick** · February 3, 2021, 07:18 PM

Bucksnort1,

Typically, when you get a short case in 45 Auto, the extractor of your pistol stops the cartridge going forward and enables it to fire. If you were firing it in a revolver without moon clips, then it might be a problem, sliding forward beyond the point where the firing pin can hit it solidly.

Unlike high-power rifle cartridge cases, 45 Auto cases tend to shrink with every load cycle, so finding short ones isn't unusual. An alternative to try (work the loads up) is headspacing on the bullet. I and others have found this to reduce leading and improve accuracy significantly. You just seat the bullet out until a cartridge dropping into your chamber sits flush with the barrel extension (hood). As long as this length doesn't cause a magazine fit or feed problem, it works very well.

Old_School · February 3, 2021, 08:11 PM

Quote:

Originally Posted by Unclenick

An alternative to try (work the loads up) is headspacing on the bullet. I and others have found this to reduce leading and improve accuracy significantly. You just seat the bullet out until a cartridge dropping into your chamber sits flush with the barrel extension (hood).

I started to bring this up, but figured I was in the minority since I still load LSWC for most handgun. Not sure how it would work with plated RN bullets that so many seem to use these days.

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74A95 · February 3, 2021, 08:12 PM

Quote:

Originally Posted by RC20

Make sure they are not 45 GAP (shorter glock case)

45 GAP has a max length of .760". That's a mile away from what the OP measured.

https://saami.org/wp-content/uploads...sting-Copy.pdf

**Aguila Blanca** · February 3, 2021, 09:20 PM

Quote:

Originally Posted by Unclenick

An alternative to try (work the loads up) is headspacing on the bullet. I and others have found this to reduce leading and improve accuracy significantly. You just seat the bullet out until a cartridge dropping into your chamber sits flush with the barrel extension (hood). As long as this length doesn't cause a magazine fit or feed problem, it works very well.

The problem with this method is that it creates cartridges that may only work (right) in one pistol. I have three 1911s that I keep in carry rotation, two that are mainly for competition, and a couple of others "just because." I don't reload for any one of them in particular -- I want my loads to work in whichever pistol I happen to pick up that day.

RC20 · February 4, 2021, 12:24 AM

That said I did shoot a couple of 45 GAP in a 45 ACP

Shoots fine, does not cycle at all but firing was not an issue.

Make you wonder about head spacing on the mouth of the case? (or not believe it at all!)

Quote:

45 GAP has a max length of .760". That's a mile away from what the OP measured.

Always worth a check and it was around.

ballardw · February 4, 2021, 05:26 AM

Quote:

Originally Posted by RC20

Make you wonder about head spacing on the mouth of the case? (or not believe it at all!)

I take that a evidence that John Browning was even more of a genius that many thought.

Or does this work for other than 1911s as well?

RickB · February 4, 2021, 12:02 PM

When I started loading .45, I adjusted OAL so the SWC bullet shoulder would create consistent chambering depth regardless of case length, but over time, measuring a lot of cases, etc., I've just come to ignore case length.
While longer brass is better than short, G.I. chambers can be as deep as .920", so a fine fit of case and chamber is never assured.
When I had the opportunity to have a chamber reamed, my gunsmith recommended .905".

February 3, 2021, 03:19 PM	#1
Bucksnort1 Senior Member Join Date: July 8, 2013 Location: Littleton, Colorado Posts: 1,130	45ACP Short Cases I am resizing 45ACP cases. I use a case gauge to periodically check for proper fit. I have two cases, one by S&B and the other a Federal that are not flush with the top of the gauge. They are below about 1/16". Head space on semi-autos is determined by the mouth of the cartridge touching a ridge in the chamber. Both cases measure .884" - should be .898". These are at least once fired cases which I picked up at a range. I will toss these two but out of curiosity, is there a danger in loading and shooting them?

February 3, 2021, 06:52 PM	#4
RC20 Senior Member Join Date: April 10, 2008 Location: Alaska Posts: 7,334	Make sure they are not 45 GAP (shorter glock case) __________________ Science and Facts are True whether you believe it or not

February 3, 2021, 07:18 PM	#5
Unclenick Staff Join Date: March 4, 2005 Location: Ohio Posts: 21,742	Bucksnort1, Typically, when you get a short case in 45 Auto, the extractor of your pistol stops the cartridge going forward and enables it to fire. If you were firing it in a revolver without moon clips, then it might be a problem, sliding forward beyond the point where the firing pin can hit it solidly. Unlike high-power rifle cartridge cases, 45 Auto cases tend to shrink with every load cycle, so finding short ones isn't unusual. An alternative to try (work the loads up) is headspacing on the bullet. I and others have found this to reduce leading and improve accuracy significantly. You just seat the bullet out until a cartridge dropping into your chamber sits flush with the barrel extension (hood). As long as this length doesn't cause a magazine fit or feed problem, it works very well. __________________ Gunsite Orange Hat Family Member CMP Certified GSM Master Instructor NRA Certified Rifle Instructor NRA Benefactor Member and Golden Eagle

February 4, 2021, 12:02 PM	#11
RickB Senior Member Join Date: March 1, 2000 Location: Boise, ID Posts: 8,559	When I started loading .45, I adjusted OAL so the SWC bullet shoulder would create consistent chambering depth regardless of case length, but over time, measuring a lot of cases, etc., I've just come to ignore case length. While longer brass is better than short, G.I. chambers can be as deep as .920", so a fine fit of case and chamber is never assured. When I had the opportunity to have a chamber reamed, my gunsmith recommended .905". __________________ Runs off at the mouth about anything 1911 related on this site and half the time is flat out wrong.

February 3, 2021, 03:36 PM	#2
74A95 Senior Member Join Date: November 26, 2016 Posts: 1,674	No. No danger.