45 ACP Question

[jcw1970]

While reading Sharpe's book on reloading, he said to never crimp a 45acp when reloading because it relies on the case length for proper head space. I feel pretty stupid asking this question but is this right? I've always put a slight crimp on mine to keep the bullet from shoving back into the case on feeding.

[snaggdit]

I can't see a crimp changing the case length more than a few thousanths. I agree, I worry more about feeding shoving in my boolits. Looking forward to the experts chiming in on this, too.

[kawalekm]

You can crimp, in two different ways. You can add just enough of a roll crimp to remove the flare you made for bullet seating. For my .45, I had to take it a step further. My case mouths were a few thousandths too big and my rounds were failing to feed fully till lockup. I had to taper crimp just enough to reduce the mouth diameter about 3 thousandths.

In either case though you must pay attention that the case-mouth still has enough of a ledge to stop at the end of the chamber. This is very easy to do with the barrel removed from the gun. Just drop a loaded round into the chamber and listen. It should stop with a distinct metallic "click". The rim of the case should be flush with the back end of the barrel.

Good luck to you,
Michael

[jhalcott]

A lot of new guns will handle crimped ammo very well. The extractor seems to hold the case back enough for for the pin to hit the primer. Some people will use a case to death. This is usually a bad idea, as the brass becomes brittle and doesn't hold the bullet as tight as it should. That's when the bullet can move in or out of the case. Often the bullet goes into the rifling when chambered.

[Dale53]

I adjust the bullet seating depth until the case head is flush with the barrel hood. I taper crimp to .469"-.470" (diameter of the very end of the case mouth over the bullet). By controlling headspace with the bullet, as this does, you get consistent ignition.

Dale53

[fredj338]

Sharpe's book was written at a time when many 45acp ammo was loaded w/ a die that roll crimped. All of todays dies taper crimp & it's pretty diff. to over taper crimp. While the extractor may or may not hold the case in place, the 45acp does headspace on that tiny ledge so you don't want to roll crimp unless it's very. very slight.
Bullet setback, you can't crimp enough to keep that from happening. Proper case neck tension is needed. That comes from proper sizing & case expanding. If you have setback issues, try polishing down the expander 0.001", it really helps.

[Echo]

I've raised hackles before, but don't mind doing it again - the .45ACP DOES NOT HEADSPACE ON THE NECK OF THE CASE. Take your depth mikes and measure the depth of the chamber - you will find that it is several thousands longer than the case length. It headspaces on the boolit, with help (I suppose) from the extractor. High-powered pistoleros* taught me this.

I always seat my -460's with the shoulder out about 40-50 thousandths from the neck. If I were to remove the barrel from my wad gun and drop a round into it, it would stand up some proud - but the slamming of the slide into battery will engrave the boolit and provide enough
support for consistant ignition. I taper crimp my rounds.

*Jim Clark, Dick Shockey, Bob Day, and others...

[fredj338]

Maybe that is your pistol & your load, but where is the shoulder on a 230grRNL or RNFMJ? If I drop an empty sized case in the chamber of any of the various 45acp I own, the case hits the end of the chamber & the base is pretty much flush w/ the hood. Hmm? Plus every relaoding manual I have ever read states the round headspaces on the mouth of the case. While some pistols MAY allow the extractore to support the case, it shouldn't be relied upon. A worn extractor + out of spec case + too much crimp & you are asking for a misfire. Not to mention I do not want my +P loads jambed into the rifling. Just food for thought.

[inuhbad]

Buy a case gauge and check each loaded round. Works great for me, ensures consistency, and helps me catch some loaded rounds with defects.

[BruceB]

This subject comes up regularly. I think the last occurrence here was only a matter of a few weeks ago.

Hear this: it doesn't matter HOW you load your ammo for the common .45 ACP pistols, as long as it chambers freely and doesn't have excessive headspace....meaning, seating too deeply into the chamber.

For myself, and speaking from forty-plus years with the cartridge, I have used both the roll crimp (a REAL roll crimp, with the mouth turned noticeably into the the bullet) and taper crimping. The ammo worked -and works- very well indeed, with match-capable accuracy. This "accuracy" was BULLS-EYE competition accuracy, which demands 50-yard groups of under 3" for ten rounds. I don't shoot Bulls-eye any more, so my "acceptance standards" are a good bit looser....all I really want now is perfect function.

Whichever crimp is used, my ammunition headspaces ON THE BULLET. The seating depth determines how far the cartridge enters the chamber. .45 case length is NEVER as long as the specified dimension, and I have NEVER seen a case as long as the "book figure" of .898".

Buying and using a CARTRIDGE gauge (not "case gauge", with apologies to inuhbad) for every single round is very sound procedure, and as long as the ammo seats flush in the gauge, not much else matters. Don't over-think this; just ensure the rounds gauge correctly and you'll have little trouble. I religiously gauge every round, and the labels on the boxes indicate that the gauging was in fact done. EVERY ROUND!

[mike in co]

i mentioned this elsewhere, but since you asked....read very carefully what most have said.
i have used conventional commercial 230 lrn for my cz97 45acp. load was just a little short of max. no bullet contact with the throat, and chambered well.
i added a para 1911 and a lee 225 1r rn....and it is a whole new story.
the bullet is larger on the nose, the para bbl chamber is shorter. i ended up at 1.2 for an oal.

so while the extractor will hold the case back, no mater what crimp you use, you need a consistant case length to get a consistant crimp( consistant crimp, consistant ignition and burn leads to consitant accuracy). so pick an oal that keeps the bullet claose to the throat, then a min crimp to ensure the case does not hang up on feeding.......maybe a thou under case mouth spec of a loaded round. load a few and try them , if no issue load a bunch, if issues consider a tad more crimp/and or a little shorter oal.
for safety's sake consider a powder charge that is at least 50% of case volume( never a double charge)
mike in co

[inuhbad]

Buying and using a CARTRIDGE gauge (not "case gauge", with apologies to inuhbad) for every single round is very sound procedure, and as long as the ammo seats flush in the gauge, not much else matters. Don't over-think this; just ensure the rounds gauge correctly and you'll have little trouble. I religiously gauge every round, and the labels on the boxes indicate that the gauging was in fact done. EVERY ROUND!Sorry! :-D

I've only been loading since '03, so I'm a relative newbie to reloading, and have only started casting my own in the past ~6-9 months or so... So I'm an extreme newbie on casting.

I forgot the 'technical' nomenclature. Yes, it's a Cartridge Gauge.

I was having a similar problem to what the Original Poster is quoting. I first had that problem with my 380 ACP rounds that were getting 'tight' in the chamber due to slight bulging. I talked to a guy at the reloading shop, he pointed out the cartridge gauges, and I bought one for each caliber!

They're only about $15 bucks, and they're some of the best money I've ever spent in reloading stuff! I now check every single round in the gauges, and it has saved me countless headaches, and helped me to find where I was going wrong.

Turned out the bulging was due to one of my dies 'loosened up' and it was slowly drifting out of adjustment and I hadn't even noticed it! It was so slight, but quite obvious once I had the case gauges!

I now do a very slight taper-crimp on my 45 ACP (and other similar ACP / straight cases), and I've never had a single problem since!

Well, at least not one that the cartridge gauge didn't catch ahead of time... :drinks:

[TAWILDCATT]

I am with ECHO:I too shot compitition and I roll crimp medium.all the older compeditive shooters roll crimped.there were no taper crimp tools. an they all shot 3.5 grs of bulleseye with 185 or 200 gr SWC.only with jacket bullets did they not crimp.I knew Hamilton and he crimped.none of you heard of him I suppose.and B Colt.I followed Dinens advice.roll crimp with SWC just 1/32 out of case.I shoot an AMC longslide and an AMT hardballer.I have another 45 a Fed ornance just as good. :coffee: [smilie=1:

[Echo]

If I drop an empty sized case in the chamber of any of the various 45acp I own, the case hits the end of the chamber & the base is pretty much flush w/ the hood. Hmm?

Pretty much? Meaning? Ten thousandths short can be defined as 'pretty much'...

[35remington]

Since the cartridge was certainly not designed to headspace on the extractor for reasons having to do with reliability and desirability, the most common situation is to either headspace on the bullet or on the end of the case mouth depending upon the type of bullet loaded and how it is seated, and whether factory loads or handloads.

The 45 ACP was indeed designed to headspace on the case mouth; this is a far more common occurance than extractor headspacing, especially with jacketed factory ammo.

It is possible, with a very short case and a very long chamber, to headspace on the extractor, but the case mouth or bullet is the most common situation. In jacketed factory loads, headspacing on the case mouth is most common, and is far more likely than extractor headspacing unless the factory grossly mismanaged their case lengths, which is unlikely given QA checks in the loading process. Even short throated guns usually headspace on the case mouth using jacketed factory loads. This is to be expected for clearance reasons. Bullet headspacing is more of a reloading affectation since factory loads must fit many different guns, even those with short throats, and little full diameter bearing surface can be present ahead of the case mouth.

Keep in mind that those that claim the 45 ACP case gets shorter with use also must acknowledge the case lengthens when sized approximately five to six thousandths of an inch from its fired dimension. This makes extractor headspacing a very distant third in the "what does the 45 ACP headspace on" argument.

If your gun is headspacing on the extractor, better change how you're loading the 45 ACP or get the dadgum gun fixed. It's not a desirable situation.

A case with ten thousandths clearance between the end of the hood and the base of the case is nowhere near to headspacing on the extractor. Such a case, assuming the bullet does not strike the leade first upon chambering, will headspace on the case mouth. Per some reliable measurements from a gunsmith friend that specializes in 1911's, the disparity between chamber length and case length must get quite large for the rim to headspace on the extractor. That's more clearance than even many times fired short cases and long chambers exhibit.

Feel free to take your own measurements.

A comment from m1911.org:

"The extractor (alone) of an average M1911A1 can hold the case no closer than about 0.040" to the breechface. In addition, the built-in interference between the extractor nose and the extraction groove bevel tends to force the case away from the breechface.

This for a plain untweaked GI 1911 built to Army specs."

If the extractor can't hold the case close to the breechface upon firing pin impact (the rim must headspace on the front of the extractor hook to resist the firing pin blow) it's not too likely the extractor will headspace the round - the case mouth will hit the front of the chamber before the rim hits the end of the extractor hook.

JMB settled on the extractor location versus chamber depth and this was standardized with tolerances for a reason; to make sure the extractor didn't headspace the round in the vast majority of instances. They succeeded.

Yes, it is possible to have an out of spec gun due to "tolerance stacking" but this is not the typical situation; oftentimes such "tolerance stacking" is not due to "stacking" but simply to out of tolerance parts. For some reason some like to claim that "no tolerances" exist for the 1911, but they do indeed exist for the reason that parts must interchange, and the vast majority of the time the extractor location and chamber length prevent extractor headspacing. Even with pretty short cases. Other types of 45 autos have tolerances that prevent extractor headspacing as well.

Just because some parts and guns when combined result in excessive tolerances does not mean the majority do.

Taper crimping does not improve bullet retention. It's intended to turn in the flare of the case mouth from the belling step.

[Beekeeper]

OK, Help out a dummy here.
I have been loading rifle with j bullets for 40 years and have never used a overall legnth guage.
Looked on the Midway USA website and found a flat piece of metal with notches cut in it.
Is this what you call an overall cartridge legnth guage?
If no point me in the right direction so I can see what I have been doing wrong all these years


beekeeper

[35remington]

No. Those sheet metal cutout thingies measure case length only.

A cartridge gauge looks like a short cylinder, and is cut to minimum SAAMI chamber dimensions, with an overall length no longer than the maximum SAAMI spec for the cartridge when loaded with a bullet in place. However, just because it fits the gauge does not mean the bullet's bearing surface will not hit the rifling leade, since it does not take into account leade length of a given barrel and amount of bearing surface of the bullet outside the case.

They are very useful, though, since if the diameter fits the gauge, the diameter should fit your chamber. I am specifically excepting bullet bearing surface/leade contact in your particular gun. That means overall length must be checked in your gun's chamber to ensure bullet/leade clearance.

[MtGun44]

35 rem is right and all the folks that claim that the extractor headspaces a .45 ACP (1911)
have never bother to even check it out.

Take a case that measures shorter than spec (hint they ALL do). Pull the top off the pistol,
chamber the empty case and then push/pry it hard to seat fully against the end of the chamber.
Now, look very closely, with a bright light and a magnifier if you
need it, at the clearance between the extractor hook and the case rim. In the 1911s I have
checked there is about .040+" clearance. I suppose it is possible that somewhere in the
world there is a case that is more than .040" short, but the second check is to take the
barrel out of a 1911 and fully assemble it and put a popsickle stick or similiar device about
3/8"" fwd of the breech face and drop the hammer. The firing pin will hit the stick. Still think
you need the extractor to hold the case back so the firing pin can hit it? The primer could be
1/4 " away from the breech face and it would get hit.

The guys that said that they headspace on the bullet are OK, and that can work just fine but
is not necessary. Any jacketed boolit in a normal chamber (many match chambers are
WAY not normal, I own several) will not headspace on the bullet, but on the case mouth.

I am amazed at the folks that comment about this without ever having actually looked at the
dimensions involved. Apparently they read this somewhere and took it for gospel without
actually looking inside the gun and doing some measuring.

For any remotely normal .45 ACP brass (all is short of trim length except a few match
cases that come almost up to trim to length) will headspace on the case mouth and never
get anywhere near the extractor. Setting up you ammo so the bullet is forced into the
rifling seems OK because the .45 ACP is THE most forgiving round to load, altho the .38 Spl
is about equally easy and safe. It may well increase accy in some guns, too. I am not
suggesting that this is a bad idea, but just a non-std practice that needs to be applied
carefully - in some rifle ammo it can be dangerous, and possibly in some pisto ammo.

For best feeding reliability in .45ACP, taper crimp until the brass is about half thickness pushed into
a lead boolit and make sure you don't have so much of the full diameter portion of the boolit
out of the case to cause failure to chamber fully due to interference with the rifling. Roll crimp
will work and will provide good accy. Most of the Camp Perry top shooters in the old days used
roll crimp and got great accy. I theorize that they were headspacing on the boolit shoulder with
a H&G 130 or similar SWC. I'd love to have some of their ammo and a barrel to examine.

Take the extractor out. Try a primed .45 GAP case and see if it will fire in a .45 ACP 1911. I'd
bet it would. Not a .45 GAP would likely headspace on the extractor, but very unlikely any .45 ACP
case would ever get there.

Bill