45 ACP Min Case length

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.
 
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!
 
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?
 
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?
Click to expand...

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.
 
Anglicanman,

As far as I know, if you don't want to headspace on the extractor and you have short cases, headspacing on the bullet is the only alternative.

If it is any comfort, the 45 Auto cartridge's powder space under the bullet is so small the primer often makes enough pressure to unseat the bullet before the powder burn gets very far underway. So, powder gas pressure often builds with the bullet in contact with the throat anyway. What is different is jacketed bullets are hard enough to steer the cartridge straight when this occurs, while lead tends remain cocked a bit. That's why it deforms.

Another factor is headspacing on the bullet keeps the primer a consistent distance from the breech, so the firing pin jump is consistent. I don't think that makes a big difference to handgun accuracy, but it can't hurt ignition reliability.
 
Thanks for the note about SAAMI! I find a couple of interesting things as I measure cases; for one thing the case mouth is not exactly parallel with the base. If I turn the case I can sometimes vary the measurement in my caliper by a few thousandths. Today I loaded about 170 rounds and just figured if a case is between .888 and .898 it will seat on the case mouth. Half the cases at least, of the ones I have, are too short.
I wonder what the original specification way back in 1912 was for cases. Do you know?
I read the discussion about chambering off the extractor and that with jacketed bullets it may not affect accuracy all that much; just wonder sometimes about doing things in a way Mr. Browning did not intend for them to be done.
And so ... if a person plans to seat the round off the bullet into the rifling how can the overall length of the round be determined? I will have hundreds of too short cases after I use up all the ones which fall in the 10 thousandths range of OK.
 
OK, Uncle Nick and 44, I am starting to get some ideas. I have 4 .45 ACP pistols and I suppose I could take all the barrels out and find out somehow how to get the base of the cartridge to match the barrel end as Nick shows. I could then load bullets that far from the case mouth for each barrel and segregate them somehow except that even with cases all for one barrel case length is a variable which will influence how far a bullet has to be out in each individual case.
Maybe I am getting too worked up about all this, after all eveythng I read seems to say that .45 ACP in 1911 is not all that fussy.
I come to reloading from a background in Motorcycle mechanics. If someone told me that piston ring end gap, for example, is supposed to be .006" +/- .010" I would not know how to act.
 
Your press seats the nose of the bullet a fixed distance from the backside of the case head. So, if you set the seating die up to produce the length you see in the third image from the left on my drawing, you will get that from every round regardless of case length. It improves consistency of start pressure that way, which is part of why it improves accuracy.

I have found that lead bullets are soft enough that if you have five thousandths of the kind of protrusion you see in the last image on the right end of the drawing, the recoil spring is usually strong enough to seat them anyway. If the head of the case is five or ten thousandths below the back end of the barrel extension (hood), the bullet has started into the throat and will stop before the rim hits the extractor hook in most instances. So there is really a range of bullet lengths that still work well in each gun.

Find which gun makes you seat the bullet deepest and then drop a sample round in the other barrels and see which one lets it fall furthest in. See if that is far enough that the extractor hook will catch it before it goes that far or not. If not, it will usually shoot pretty well and you can use that same seating dept for all you guns. Otherwise, you may find two seating depths, each of which satisfies two of the guns and can divide the ammo up that way. Then you just have to learn how far to turn the seating die setting to switch.

The taper crimp die will have some sensitivity to case length. You want the case mouth to wind up between 0.467" and 0.473" diameter at the mouth for normal headspacing. A lot of the target shooters the '40s, '50s, and '60s both headspaced on the bullet and applied a roll crimp (since the case mouth wasn't close enough to the throat to cause a problem) for extra bullet pull and start pressure and swore that produced the most accurate ammunition. It is probably hard to find a 45 Auto roll crimp die these days. The one I have is in an ancient RCBS die set.
 
Hi Nick and 44;
It's been a few days since I have been on this forum.
I loaded a bunch of 185 gr plated swc rounds at three different lengths, all in cases which measured between .888 and .892 or so (I have never seen a .898 case yet) and found that when I went really short in OAL there were failures to feed I think because the bullet was seated too far in so that the case mouth got hung up on the feed ramp. 1.125 I think, was too short.
Now I have a bunch of cases (a few hundred at least) which are below spec. If I load those to an OAL of 1.250 or so, a length long enough so that when I do a plunk test in a barrel the base of the case is about flush with the hood will that be the way to go? I think that those rounds might well plunk into the barrel but they might not fall out as the bullet might stick in the rifling a bit. I have found that there have been cases where the round would plunk into my spare barrel but I would have to hook onto the rim with my fingernail to extract the round. Your thoughts? I hate to just throw a couple of hundred cases away. I would not be loading the SWC but plated 230 gr round nose. I realize I would be headspacing off the bullet not the case mouth.
 
Getting the case flush with the hood is what works for me. What cartridge overall length that produces will vary with the bullet design. Seating too deeply can also raise pressure or else cause the primer to start unseating bullets ahead of powder burn, which tends to cause irregular velocities, so seating too deeply is not good from that standpoint. It also tends to cause headspacing on the extractor hook when it is deep enough.
 
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