Interesting , not head spacing on the case mouth

[Johnch]

But 100% relieable ( 50 rounds )

Tonight I was cleaning the reloading bench
When I found 50 rnds of loaded ammo , with one of my reload info stickers on the box
I remember loading it , but for the life of me
[smilie=1: Can't figure out WHY I loaded it [smilie=1:

It was my standard 9 MM load , 125 gr Boolit , powder charge and OAL
But loaded in 380 cases
With 9mm dies

I even remember I loaded it on the Dillon Sq Deal press

Well the GF is always looking for 380 cases for me to load
So I figured I would pull the boolits

But I got the bright idea to try and just shoot them in the High Power
As it would be faster if I could get them to go off
Even if I had to single load them

So I headed to my 25' range in the basement

Well I stuck 13 rnds in the mag

Worked the slide and proceeded to get a decent 13 shot group ( decent for me )

Figuring it was a fluke , so I loaded the rest of the box into mags
And shot them , not 1 failure to fire

So my only guess is the extractor held the case in place well enough to allow the firing pin to strike the primer

No I am not planning on loading any more , or trying 380 ammo in the 9mm High Power

But I found the fact that I had no problems with either the 2 mm shorter case head spacing or the smaller head size interesting

John

[spqrzilla]

Formally, auto pistols mostly headspace on the case mouth ( exceptions exist like the original .38 ACP / .38 Super ... ).

Practically, auto pistols headspace on the extractor ...

Problems arise when the cartridge does not slip under the extractor and gets pushed forward, in extreme headspacing situations.

[geargnasher]

In my experience, many autoloading pistols depend more on the extractor claw to maintain headspace than the end of the chamber or the boolit/bullet. Most 1911's I've checked with the external claw are an exception.

Gear

[HeavyMetal]

This is one of the reasons most will suggest you use the barrel, in a 1911 for example, as a "guage" to set up your COL.

In essance your using the bearing area at the begining of the ogive( If your loading round nosed boolits, the forward edge of the first driving band if loading an SWC) to set the "head space" by seating the boolit out far enough to touch the leade of the rifling and keep the case head flush with the hood of the barrel.

An old trick, particularly useful with the 38 super cartridge, aids in accuracy as well.

Seen many a sqabble over the idea that auto loader head spacing might be controlled by the extractor rather than the case mouth.

A nice example of how things work in the real world!

[mooman76]

I picked up some 9mm at a range once that looked very strange. Aparently someone had loaded a mag of 9mm in a 40 and fired them.

[Dannix]

Interesting posts here.

I regards to what HeavyMetal said, I've heard some touting going for an OAL all the way to the rifling, particularly in long guns, but I've also heard this is a great way to increase cartridge pressure and kaboom. Thoughts?

[leftiye]

If you work up pressures as part of your load development???? Then pressures will be taken care of. Much more increase in pressures occurs if your boolit gets pushed back into the case. Most of my rock shooting loads (minute of mountain?) are set up this way, but are lower velocity/pressure loads anyway.

[exile]

Wouldn't the fact that they were loaded in .380 cases increase pressures, or does the fact that they were loaded to the same overall length as 9mm. take care of that?

Glad everything worked out ok.

exile

[Buckshot]

..............Years back, one of the old gentlemen (Freeman) who'd be at the range every Tuesday ran his own experiment as regards truly headspacing on the casemouth or the extractor. His experiment was with the 45 ACP, and he had one of the first Kimber target 1911's. He was a WW2 vet and before we got into the war he was in England as a pretend civilian working as laison between their radar scientists and the U.S. development teams. After the war when he left the military he worked for several top flight outfits and was instrumental in early work on guided missles and inertial navigation equipment. He was probably one of the most naturally intelligent persons, besides his schooling I'd ever met.

I only mention this because his approch was very methodical, and by his nature he was curious as to the outcome regardless what he found out. He used Winchester 45 Mag cases and trimmed them back to actually headspace on the casemouth. The 45 ACP case is supposed to be something like .898" long, but finding them as short as .888" isn't uncommon. He ended up with cases of .900" something. IIRC something like .905" for the mag cases to headspace on the mouth.

His control ammo was a new 50 rnd box of R-P 230gr ball which was fired for group. After reloading the once fired 45 ACP cases and his also once fired Win 45 Mag brass with the same loads, he fired five 10 round groups of each off the bench at 25 yards. At the conclusion of his test he said there was zero statistical difference in accuracy between the longer true mouth headspacing ammo, and the standard run of the mill shorter 45 ACP cases. Naturally he also added that that was so far as his Kimber was concerned, and his reloads were better then the factory ammo :-)

................Buckshot

[Dannix]

^Interesting post Buckshot. I remember reading somewhere, perhaps here, where someone was all upset about manufactures making 45 ACP ammo 'dangerously' short. I didn't pay too much attention because I'm not a 45 guy, but I guess it was just much to do about nothing. Maybe it is of some concern though, concerning dependability, not accuracy, if you're in harms way though?


If you work up pressures as part of your load development????
I have yet to get into the realm of rifle reloading, but if I recall correctly, I was told somewhere like Benchrest Central or someplace, that working up a low-pressure rifle based on pressure signs will result in a blownup gun because the gun will reach its max before, say, the primer pocket does.

My understanding of working up loads in low-pressure cartridge rifles is lacking I'm sure though. Considering the Benchrest Central guys are really pushing their rifles, I imagine they use a whole different set of pressure signs. For general purpose, just get a chrono and check it against manual values?

[EMC45]

My brother once loaded a magful of .380s in my Beretta M92. He got about halfway through the mag and it jammed. He asked what was wrong with my gun. I said it was the shooter not the gun......

[HORNET]

Several years ago I got tired of loosing .38 Super brass and loaded a batch up in 9 mm cases using a 148 wadcutter and set the OAL to headspace with the boolit to the rifling. Looked very strange but worked fine and I didn't hunt too hard for those cases. I had a bucket full of 9 mm brass and no gun for it.

[MtGun44]

I would suggest that anyone that believes that the .45 ACP usually headspaces on
the extractor actually put a dummy round set up the way they load, into the barrel
with the slide assembly dismounted from the frame.

In my experience, there is about .020-.030" or more clearance forward to the hook on the
extractor from the front face of the rim in normal ammo. The extractor is NOT holding
the round in a couple of 1911s that I checked. I did not check them all.

CAN it do this? Actaully I doubt it is actually possible with any commercial piece of .45ACP
brass, but I am not sure. Does it actually? Not in either of the two guns that I
have looked at. Doesn't prove that it never happens, but I do not think the normal 1911
dimensions will actually support this theory.

This only takes a minute and you will see with you own eyes, much better than
any theory that any expert may expound upon. Don't believe? Prove me
wrong by actually looking at the pieces as they are located in a 1911 with a loaded
(dummy) round. Maybe everyone else's guns are fit up differently than the
ones that I looked at, maybe I have bad samples.

This is an oft repeated theory and is malarky IMO. It seems that .45 ACP ammo
headspaces on either the case mouth or the boolit in the throat, probably the boolit
in the throat in most guns. I think even the shortest case you would find will hit
the front of the chamber before it hits the extractor hook. Are any cases out there
that are greater than .020-.030 shorter than normal?? This would be necessary
for my guns to get the rim front face out to reach the extractor, completely discounting
the bullet hitting the throat at some point, too.

Note that the 1911 firing pin will protrude WAY out, 1/2" or more, so no matter
where the round is, the firing pin will find it!

As a mostly unrelated issue, I think you could easily fire a .45 Gap round in a 1911
with the extractor removed because even if the round were FAR forward, the firing
pin would probably hit the primer. Anyone with a 1911 and an empty .45GAP
case can try to set off a primer-only with the extractor removed and a resized
case only to see if this works. I have not done this.

Come to think of it, I have seen several 1911s with the extractor hook broken off
and they fired normally except for failure to extract.

Bill

[mike in co]

I would suggest that anyone that believes that the .45 ACP usually headspaces on
the extractor actually put a dummy round set up the way they load, into the barrel
with the slide assembly dismounted from the frame.

In my experience, there is about .020-.030" or more clearance forward to the hook on the
extractor from the front face of the rim in normal ammo. The extractor is NOT holding
the round in a couple of 1911s that I checked. I did not check them all.

CAN it do this? Actaully I doubt it is actually possible with any commercial piece of .45ACP
brass, but I am not sure. Does it actually? Not in either of the two guns that I
have looked at. Doesn't prove that it never happens, but I do not think the normal 1911
dimensions will actually support this theory.

This only takes a minute and you will see with you own eyes, much better than
any theory that any expert may expound upon. Don't believe? Prove me
wrong by actually looking at the pieces as they are located in a 1911 with a loaded
(dummy) round. Maybe everyone else's guns are fit up differently than the
ones that I looked at, maybe I have bad samples.

This is an oft repeated theory and is malarky IMO. It seems that .45 ACP ammo
headspaces on either the case mouth or the boolit in the throat, probably the boolit
in the throat in most guns. I think even the shortest case you would find will hit
the front of the chamber before it hits the extractor hook. Are any cases out there
that are greater than .020-.030 shorter than normal?? This would be necessary
for my guns to get the rim front face out to reach the extractor, completely discounting
the bullet hitting the throat at some point, too.

Note that the 1911 firing pin will protrude WAY out, 1/2" or more, so no matter
where the round is, the firing pin will find it!

As a mostly unrelated issue, I think you could easily fire a .45 Gap round in a 1911
with the extractor removed because even if the round were FAR forward, the firing
pin would probably hit the primer. Anyone with a 1911 and an empty .45GAP
case can try to set off a primer-only with the extractor removed and a resized
case only to see if this works. I have not done this.

Come to think of it, I have seen several 1911s with the extractor hook broken off
and they fired normally except for failure to extract.

Bill

me thinks we have been thru this before.
not all semi auto guns will hold a case back close enough for the firing pin to ignite the primer,BUT a significant number of them do.

so no it is not a generic statement that "ALL SEMI AUTOS FIRE FROM THE EXTRACTOR AS OPPOSE TO THE CHAMBER/CASE LENGTH".
but it is also not correct to "ALL 1911'S FIRE FROM THE CHAMBER/CASE "
REMEMBER the subject is shooting a SUB CALIBER from a given gun...IE a 380 in a 9mm,, it is not about shooting long or short cases in a cliber specific gun....long or short 45acp in a 45acp.

the EAA witness i just bought in 10mm is giving me fits with jams. no combination to date has fired a full mag without a jam or two.
take the same gun with the same mags, and load them with 40 s&w.....and the gun functions 100%. no failure to fire, extract, no failure to feed.

AGAIN THE SUBJECT THIS TIME IS SUB CALIBER IN A GIVEN GUN IE 380 IN A 9MM.

i am in the brass business, i see it all the time.

mike in co

[9.3X62AL]

Mike--

Sorry to hear about the Witness acting the fool. Any ideas on what will correct it, short of sending it back for warrantee work? I assume you've played around with OAL and all that.

YES, headspace/chamber clearance and how autopistols achieve it (or don't) is a fertile field for cultivating controversy. I don't have a firm conviction either way, really. Most of that is based on concerns running in other directions with my stutterguns--reliability and accuracy. Once those are established, the finer points kinda blur out for me.

As for the idea of a cartridge's boolit contacting the leade........I do that very frequently in rifles and autopistols with cast boolits. The loads are worked up from well below max, and a chronograph is used to extrapolate pressures from the achieved velocity and gauge consistency. With jacketed bullets, I scrupulously avoid letting the bullet ogives contact the rifling leade. I also work loads up (both cast and jacketed) in hot weather for the most part, to guard against environmental heat prompting a pressure excursion in the Mojave Desert on a jackrabbit strafing safari.

Murphy's Law, and when it comes to reloading regimen--Murphy can be naively optimistic.

[C.F.Plinker]

After another discussion about headspacing the 45ACP on this site I took a once fired round of WCC Match brass, sized it, and then dismounted the slide and barrel from one of my 45s. Setting the barrel forward of lockup so it only served as a guide for the cartridge case I inserted the case in the extractor and started inserting paper shims between the bolt face of the slide and the head of the case. The shims measured .048 inches with the same resistance to pulling between the caliper jaws as there was between the bolt face and the head of the cartridge. Next I moved the barrel into lockup and measured the gap between the cartridge head and the bolt face the same way. Now it is down to .017. This means that I will be headspacing on the case mouth rather than on the extractor. Lastly, I took a dummy cartridge that has a 185 grain Saeco semi-wadcutter and measured .017 between the case head and the bolt face. Removing the barrel and dropping the dummy cartridge case into the barrel I saw that it came to rest below the hood. BTW the distance from the hood to the step that the case headspaces on is .910 inch. When I took one of the Saeco Boolits and seated it by hand so that the head was even with the hood (headspacing on the boolit and leade) all of the front band was outside of the case and I could see just a hair of the first lube groove.

By making similar measurements you could see if your cartridge is headspacing on the extractor, the case mouth, or the bullet.

[mike in co]

After another discussion about headspacing the 45ACP on this site I took a once fired round of WCC Match brass, sized it, and then dismounted the slide and barrel from one of my 45s. Setting the barrel forward of lockup so it only served as a guide for the cartridge case I inserted the case in the extractor and started inserting paper shims between the bolt face of the slide and the head of the case. The shims measured .048 inches with the same resistance to pulling between the caliper jaws as there was between the bolt face and the head of the cartridge. Next I moved the barrel into lockup and measured the gap between the cartridge head and the bolt face the same way. Now it is down to .017. This means that I will be headspacing on the case mouth rather than on the extractor. Lastly, I took a dummy cartridge that has a 185 grain Saeco semi-wadcutter and measured .017 between the case head and the bolt face. Removing the barrel and dropping the dummy cartridge case into the barrel I saw that it came to rest below the hood. BTW the distance from the hood to the step that the case headspaces on is .910 inch. When I took one of the Saeco Boolits and seated it by hand so that the head was even with the hood (headspacing on the boolit and leade) all of the front band was outside of the case and I could see just a hair of the first lube groove.

By making similar measurements you could see if your cartridge is headspacing on the extractor, the case mouth, or the bullet.
all very good...
BUT
AGAIN THIS IS ABOUT SHOOTING SMALLER/SHORTER ROUNDS THAN THE GUN CALIBER.
this is not about 1911's/extractors/ and head clerarance( IT IS NOT HEAD SPACE)

next

mike in co

[Echo]

+1 for MG44, and Mike. As I have posted before - My Guru's, and they were champion smiths, told me that the .45 headspaced on the bullet. I see commercial cast loaded rounds with a little shoulder protruding. >I< seat my .45 boolits so that the shoulder protrudes maybe .030-.040, and am a happy camper.
I assume, since the OP had loaded his rounds on 9mm dies, that the boolits wre seated to an OAL appropriate to 9mm, and were headspacing on the boolits...

[spqrzilla]

MtGun44, I think you are misunderstanding the point, and disproving something that was not really being said.

[KYCaster]

Of course the ideal situation is for auto pistol rounds to headspace on the case mouth, but I don't think that's the point the OP was trying to make.

Like it or not, sub-caliber and short rounds will fire in most 1911's. 25ACP in 380, 380ACP in 40, 40S&W in 45, 10mm in 45, 45GAP in 45ACP...I've seen it happen many times.

And the phenomenon is not limited to 1911's...several years ago at a USPSA National Championship match where I was working as a Range Officer there was a professional shooter on the payroll of a MAJOR manufacturer who came to the match with her plastic gun (oops...did I give away her identity? :oops:) chambered in 40S&W and with 9X19 ammo. The first stage she shot didn't go well. She had to manually cycle the gun after each shot and had numerous misses. The second stage was no better so she finally asked for help. A quick trip to Wally-World for the correct ammo and the rest of the match went well.

Will out of spec ammo work in auto loading pistols? Of course it will.

Will I ever depend on out of spec ammo to work in my auto loaders? Of course I won't. :roll:

Jerry

[shooting on a shoestring]

Well thanks for the education folks. I had no idea autos could or would fire headspacing on their extractors. I also had no idea 1911s had anything close to 1/2" firing pin reach.

So what I want to know is of the .380s fired in a 9mm, is there a sizeable degredation in groups? Is such firing hard on extractors? The inquiring mind of a dedicated revolver shooter wants to know.

[Dannix]

Wow KYCaster. I would hope her performance with a working 'weapons system' made up for her, er, well... is she blond? :mrgreen:


I also had no idea 1911s had anything close to 1/2" firing pin reach.
Indeed. That was new for me as well. I wonder what the reach is for Glocks and the like. I know Glocks hit the primers hard (wouldn't hesitate to try rifle primers in mine if I ever needed to), but not sure about their reach.

Hum, maybe firearms companies will start marketing this as a 'feature' along with 'double-strike'. ;)


Wouldn't the fact that they were loaded in .380 cases increase pressures, or does the fact that they were loaded to the same overall length as 9mm. take care of that?
Think about it - by loading the cartridge to the same over all length, the case capacity as far as the powder is concerned is the same (though really, brass wall and web thickness, et al . would have to be considered as well).

[leadman]

Want to hear something scary? I trim 9 X 19 down to make 9 X 18 for my Makarov. I was curious if the Mak would fire with an untrimmed 9 X 19 case so I primed one and inserted it in the chamber. Pulled the trigger and it fired the primer!
Can you imagine what would happen if it was a full power 9 X 19???

[Dannix]

That's really awesome in a way. One thing you could try is sticking with a specific bullet for that gun or put a big scratch in the nose area of of your 9x18 mold if you're casting for it.

[MtGun44]

Well, I'll repost - I posted yesterday and it is not here. . . .

I understand exactly what the original thread was about, and I apologize for contributing
to the drift when another poster headed off into the old "headspace on the extractor"
claim. Thread drift is fairly normal, but isn't necessarily a good thing, so I will not
continue down that path, other than encourage individual examination of your own
1911s.

It is very interesting that at least one 9mm has the capability to fire substantially
undersized rounds with apparent safety. Also, apparently Mike finds that a significant
number of .40s are firing 9mm rounds and .45s are firing .40 rounds. I have found
split .40 cases that were apparently fired in a .45. Seemed like there was enough
intact case to seal the breach, so may have been no drama.

Probably is bad for accuracy. ;-)

Let's see if this one dissappears.