45 ACP Min Case length

[brokenarrow41]

What is the minimum size case that will still work effectively? I'm new to reloading 45ACP and still used to the 30-06 stretching every time.

[AK103K]

Your loading manual should give you that on the fist page of each rounds load data.

My Speer manual says trim length for .45 ACP is 0.888 max is 0.898. My Hornady manual says its 0.893 and 0.898.

With straight walled pistol brass, I never check OAL, and shoot/load them until the case fails, which is usually a split neck. Its also usually a good long time before that ever happens too. Literally years of constant use in most cases.

[brokenarrow41]

Thanks, I'm using a Sierra Bullets Reloading Manual "Second Edition" It doesn't have minimum case length for any cartridges. Like I said, I've never been able to load without trimming and I appreciate the help. I have some cases as short as .893 and I'll give them a shot.

[AK103K]

Reloading pistol is a bit easier than rifle. You dont normally have the case worries and work like you do with rifle brass. Its also longer lived.

You may want to upgrade your manual. I think Sierra is up to its 5th edition now.

What kind of bullets are you using and what were you thinking for a load?

[brokenarrow41]

I'm waiting for my Midway shipment of 185 grain Nosler JHP's and was going to start out with 5.4 grains of Win 231 with Win primers. If they get here soon I'll be at the range this Saturday with the trial batch. Also trying out my new Bersa Thunder if I don't blow my hand off.

If all works well I'll be ordering some cheap lead bullets, I just want to get the mechanics worked out first.

[AK103K]

Blowing your gun up and your hand off wouldnt be a good start.

Lead is definitely cheaper. I usually use 200 grain LSWC's with either 231 or Universal.

[Jim Watson]

Straight cylindrical pistol cases can actually shorten with use as they expand to fit the chamber. Trimming is not normally required, I think I have seen three over-length .45 ACPs in only 40 years of handloading. And they all came along the same season with the same headstamp, probably one out of spec box sold here.

[maggys drawers]

M.L. McPherson Metallic Cartridge Reloading 3rd. edition:

45 ACP Minimum Case Length: 0.898 inches.

[Shoney]

You do not need to trim straight wall semi-auto pistol cases. They actually get shorter by a minuscule amount each time they are resized.

[Cascade1911]

M.L. McPherson Metallic Cartridge Reloading 3rd. edition:

45 ACP Minimum Case Length: 0.898 inches.


Should that not beMax Case Length ?

[Shootest]

In most manuals the trim to length is the minimum case length.
Lyman lists 45 ACP trim to (min) as 0.888, and max as 0.898

[Unclenick]

As Jim Watson said, these cases, as well as most others running below around 30,000 psi, will shorten with use. I tracked this once with a lot of Winchester cases that I reloaded 50 times with light lead bullet target loads. They were 0.025" shorter by the end of that experiment and still working.

The SAAMI specification, as someone else mentioned, is 0.898" +0.000"/-0.010". In other words, 0.888" to 0.898". However, only the maximum is critical to safety, while the minimum is more like a suggestion. The minimum is what bullet makers need in order to put a crimp cannelure in the right place and for cartridge makers to keep a single crimp die setting. If you use lead bullets and a taper crimp die, you can just keep the same COL, but adjust the crimp die down a little as cases shorten.

[HawkeyeNRAlifer]

The only change in size on my oldest 45 brass has been to the diameter of the rim from pounding into the breach face. After dozens of reloading cycles some of my cases won't fit into the shell holder on my press. Sometimes I can twist them back and forth and get them to slide in. These are normally some of my 20 year old cases, soon to be regulated to throw away hunting brass. Otherwise I wait until I get a split case mouth to toss the brass.

[Cascade1911]

Unclenick, doesn't the .45 ACP head space off the front of the case? If it does, wouldn't making the case too short result in problems getting a proper hit on the primer and maybe extraction problems? Of course it would probably take more than a few thousandths but I would think there is some point that too short would cause a problem. As I'm a newbie to .45 ACP I'm just asking, not disputing.

[Unclenick]

Cascade1911,

Chamber tolerances in the ubiquitous 1911's and in many other .45 ACP's get's pretty loose. I've seen estimates by a couple of smiths who see a lot of them that probably half or more of what comes to them are actually headspacing on the extractor hook even with new factory ammo. In other words, the extractor hook stops the cartridge moving forward before the case mouth gets to the lip of the chamber throat. Even if the barrel chamber is cut to spec, there is often enough space left between the back of the barrel and the breechface in the slide that the total headspace is out of spec.

Good extractors seem to put up with that. For lead bullet accuracy this is a poor situation, though, as the cartridge tips to the side of the chamber at firing and lead bullets aren't hard enough to straighten themselves out entering the throat. As a result, they are swaged into the bore at a slight angle, shaving some lead off on that lip, sending an asymmetric bullet mass down range and also increasing bore leading.

For lead bullets, target shooters, even going back to the 50's and 60's, switched to headspacing on the bullet. Lots of the old timers found they got much better consistency putting a significant roll crimp on the rounds to improve start pressure by stopping the primer from unseating the bullet before the powder burn got under way. In order for that roll crimp not to jam into the throat and cause a pressure hazard, the bullet had to be seated out far enough to meet the throat before the crimped case mouth went that far forward.

The problem with the roll crimping, as anyone reloading for revolver (where a roll crimp is usually required) can tell you is that case life is shortened and case mouth splits start before long. Mostly we use taper crimps in self-loaders these days in order to prevent that, but it won't stop primer pressure unseating of a bullet. Using hard cast bullets and headspacing on the bullet even earlier seems to help this situation. It improves accuracy, often significantly, and reduces leading. You just have to use a bullet shape stubby enough to seat out that far an still feed from the magazine OK.

[Cascade1911]

Lots of good info there. I just checked my Springfield Mil-Spec. With Federal AE the case is about .012 below the breach face. Case is .892. I checked a handful of once fired mixed brass and .891-893 seems the norm. One out of ten was .889.

If I understand you correctly, you are suggesting that the bullet be seated far enough out so it just contacts the rifling. Yes?

[Unclenick]

I am suggesting lead (and plated) bullets be seated that way. Lead bullets not only need to enter the throat straight to remain accurate, but they are soft enough that if your press lets a round come out a few thousandths long, the gun will still close on them by forcing them into the throat.

Jacketed bullets don't seem to benefit from the special treatment, so I just seat them for most reliable feed. Lead bullets are soft enough to be prone to being distorted if they are driven into the throat if that event commences with the round pivoted to the side of the chamber against the extractor hook. Jacketed bullets straighten themselves out in the throat without damage.

[Anglicanman]

This is a pretty old thread, however I do have a question about MINIMUM case length for .45 ACP bare cases. I understand that repeated use of these, unlike repeated use of many others, does not actually lengthen the case but shortens it a bit because of case expansion in the chamber (I almost said Combustion Chamber - giving my background away). I have found a large number of my used cases measure under the stated minimum of .888" in length; some a thou or two, some by as much as .005" or even more in some cases. At what point does this become a problem, either because the cartridge spaces on the extractor hook or for some other reason?
Until I started measuring the length of the cases I never even considered this as a problem and now I wonder. Perhaps those with more knowledge can help me out.

[44 AMP]

There is below spec, and there is too short causing a problem. Max length spec is .898" Trim to length is a suggestion (NOT a requirement) and depending who's making the suggestion its usually either 0.010 or 0.005" below listed max. the idea is to trim it enough that it won't stretch enough to be over max and require trimming every time.

With the .45acp, this is not an issue. Cases are shorter than max spec and nearly always stay that way.

Go get a box of factory .45acp from a quality maker and measure the unfired case, I'll bet you a cookie its LESS than .898"

Now, the spec is for the .45acp to headspace on the case mouth, so one thinks case length is critical, and it is, if too long (very, very rare) but due to the construction of most semi autos, its not that critical if its a bit too short.

As was mentioned, with nearly all semis, too short a case will be held in place by the extractor and fire just fine. Just as too short a case fired using a moon clip in a DA revolver will be held in place by the clip, not the mouth of the case in the chamber. HOWEVER this changes when firing the .45acp from a single action revolver, such as a Ruger Blackhawk. In that gun there is a possibility that too short a case could allow a misfire.

I've never bothered keeping track of .45acp case lengths (other than seeing they're all under max length) and I've been shooting autos since the 70s and a Ruger Blackhawk in ACP since 1983.

Literally, unless you are having a problem, there is no problem with cases under trim to length.

I'm think if you had cases as short as .800 they'd still work in a 1911 (feeding from the magazine) not so sure they would be ok in a Ruger Black hawk. In my Webley Mk V, using clips, as long as they're long enough to hold the bullet, they work.

Hope this helps.

[Unclenick]

Anglicanman,

You are correct about the shortening. I once fired some Winchester 45 Auto brass through 50 reloads of light target ammo (185 and 200-grain cast bullets over 3.8 and 4.2 grains of Bullseye for 25 and 50 yards, respectively). They lost an average of half a thousandth of an inch at each load cycle and were 0.025" shorter at the end of the test.

I solved the problem of having short by headspacing on the bullet instead of the case mouth. Some adjustment of the taper crimp die on my Square Deal B press was needed over time, but the shooting was very good. Go back and look at the illustration in my post #11. I've updated the image source so it shows again.

Any case with a taper, like 45 Auto and 9 mm Parabellum can do that shortening. The problem is the carbide resizing dies we almost all use make a straight case, so the ring has to be sized for the case mouth and winds up narrowing the wider part of the taper near the head. That makes a gap between the sides of the case and the chamber that allows it to expand more than the original design had it, and that expansion pulls brass out of the length of the case. When you resize, it comes most of the way back to length, but a tiny bit of the brass is massaged permanently rearward, and that accounts for the gradual shrinkage. You don't see much of that in straight wall cases, like revolver cartridge cases.

[lee n. field]

----delete---

Thread necromancy.

[Unclenick]

Yep. It's his first post and a lot of newbies revivify zombie threads with their first posts. I think maybe it's because they joined the board due to interest in the subject matter of the thread when they read it as a non-member.

[Anglicanman]

To All,
Yes I am a complete newbie to this thread and also almost a newbie to reloading for .45 ACP. I have a Square Deal B and it and I are still getting to know one another. The latest issue is sideways primers, but I will call Dillon and get help again. I am really pleased with the way Dillon helps customers and sends little parts as needed.
Back to the case length issue; half a thou per firing as a rough estimate might give an idea of how many times the cases have been fired except that how long they were originally is an unknown.
I've used up my cast bullets; have about 2000 plated rn to load; I may well have that many used cases but I find that more than half the cases I check are under minimum spec. I have two 1911s which I bought used, both series 70s, one Gold Cup and one customized Gov Model (not by me but by a former owner) and I hate the idea of firing off the extractor but I imagine since I have so many short cases that I must have done it plenty of times before.
Uncle Nick, I did look at your illustrations of too long, too short, and just right.
I hesitate to try to locate the cartridge by sticking the bullet in to the rifling and spacing off that, but short of just tossing the short cases what do you suggest?
Great forum by the way!

[Anglicanman]

A variable which has not been mentioned as far as I know; are there overlong extractors which will extract rounds with short cases but not have the rounds space off them?

[44 AMP]

I hesitate to try to locate the cartridge by sticking the bullet in to the rifling and spacing off that, but short of just tossing the short cases what do you suggest?

I understand your hesitation, we've all heard for ever how "jamming a bullet into the rifling raises pressures, possibly dangerously...." and this is true, but the degree or risk is different between a 50K+psi rifle round and a low pressure round like the .45acp, there's a difference between jacketed and lead slugs, and there's a difference between regular loads worked up without the bullet against the rifling and loads worked up with the bullet against the rifling.

the greatest risk is high pressures and loads not intended for it being fired with the bullet in the rifling. If its allowed for in the beginning safe loads can be done with the bullet in the rifling. Muzzle loaders and scheutzen rifles do it all the time.

As to the short cases, I would just go ahead and use them for practice, or just plinking, until they actually do fail to function. If you're shooting for bullseye score, maybe keep the too short ones out of that batch, though.

Do remember that SAAMI min length specs are a voluntary standard for ammo that is going to be sold to the public, and not a "must be adhered to or the world will end" when it comes to what can work, in your personal gun.