[triehl27]

As the title says, I am curious what were the origanal ballistics on the .45acp ball cartridge and if or how it has progressed. I am guessing modern ammo is hotter then the origanl .45 cartridge.

 

[mattdus]

I cant really say much on the .45 round but I wouldent assume that modern ammo is hotter. the original 9mm parabelum round (9mm luger) was hotter than modern ammo, in fact there is some modern ammo that will not operate some original parabellum actions without replacement of the original mainspring with something weaker.

 

[MikeC]

Just doing a quick search of Federal's web site, their American Eagle 230gr ball load, AE45A, might be 20 fps faster then what I remember back when I started shooting .45ACP 22+ years ago. This is going just from memory, but I swear that the loads were either 830fps or 850fps. If they did bump the muzzle velocity up, 20 fps is not really pushing the envelope.

I can see the ammo makers being a bit paranoid since there are how many WW I era guns still out there. It is almost like the .38Spl, you can still find relatively mild loads for them because of the older guns.

Note, the Federal AE45A is rated at 850fps.

 

[ranger]

The "original" spec called for 230 gr. bullet to go 830 to 850 fps.

That's still the standard. The energy is about equivalent to the old .45 Colt round carried by the cavalry. So the standard didn't even change from the Peacemaker through 1985, about a 100 years. I don't know about 9mm.

Why would it be hotter? It's still shot through the very same guns.

 

[Hank Ellis]

Y'all got me to wondering...

I did a bit of digging on the 'Net and found a couple of sites with references.

Short story.
Cartridge, Caliber .45, Ball, M1911
STD - OTCM 36841
885 +- 25 fps

http://www.olive-drab.com/od_firearms_ammo_45acp.php
http://www.inetres.com/gp/military/infantry/pistol/pistol_ammo.html#45
http://www.ar15.com/content/manuals/TM43-0001-27.pdf

 

[Dave T]

I used to have a copy of a "Mil-Spec" sheet for 45 ACP Ball. It was dated 1968 (if memory serves). Velocity was to be 830 fps +- 15 fps. Anything from 815-845 fps would have been in spec velocity wise. There was also a good bit about muzzle flash (they didn't want much), case cannalure to prevent bullet set-back and water proofing.

Most of the factory ball ammo I have chronographed comes in between 790 fps and 830 fps (hottest was actually 828 fps). Many of those are claimed to be 850 fps by the manufacturers but I haven't seen one that fast yet over the chrono screens.

Dave

 

[Jim Watson]

There is an undated drawing in Hatcher's Notebook that specifies 820 +/- 25 fps in the 1911A1 pistol. Test barrels would give more. At one time military .45 was listed at 850 fps while commercial ammunition loaded the same but tested by SAAMI procedure was listed at 810.

 

[guy sajer]

Found a little more info

The 1943 Armed Service Forces Catalog SNL A-32 lists 885 fps out of the 10.5" barrel Thompson SMG

I have an original US issue Rem-UMC 20 rd box from 1918 listing 800 +/- 25 fps

I have a commercial Rem-UMC box of 50 from approximately 1910-12 listing "800 Feet Muzzle Velocity"

 

[CTI1USNRET]

How did they chronograph loads in 1911?

 

[MikeC]

How did they chronograph loads in 1911?

High speed photography is one way. Of course it would be tricky considering how small even a .45 bullet is. Shooter at the bench, high speed camera to his right. On the left a panel with black and white marks at regular KNOWN interval. Since the number of frames per second(fps) of the camera is known and you know the distance between each mark you can do the math and get a speed. A slide rule would be handy as well.

Yes, there were some high speed motion picture cameras back then. I remember photos, dated maybe 1900, in an encyclopedia my parents bought us back around 1968.



edited because I had a brain fart.

 

[hankster]

The Sight M1911A1

The Sight M1911A1 web pages have some info on the ballistics of the 45 ACP. In particular, here: http://www.sightm1911.com/Care/45acp.htm .

The main page is http://www.sightm1911.com/ . There's lots of good stuff there.

Hankster

 

[KAS]

High speed photography is one way. Of course it would be tricky considering how small even a .45 bullet is. Shooter at the bench, high speed camera to his right. On the left a panel with black and white marks at regular KNOWN interval. Since the number of frames per second(fps) of the camera is known and you know the distance between each mark you can do the math and get a speed. A slide rule would be handy as well.

I've seen several photos taken of ballistics back in the 20's and 30's. They used several camera's that had the shutters tripped by a wire in the bullet's flight path. Another way would be to use a single camera set a relatively long exposure and measure the streak from the bullet on the film. Since the shutter speed is known it would be a simple matter to figure out the velocity.

 

[Jim Watson]

The standard method of measuring velocity for many years was the LeBoulenge electromechanical chronograph, designed in 1860, improved in the late 19th century by Col Holden, and used for many more years. The bullet clipped a near wire which turned off power to two electromagnets. One released a long iron rod to drop vertically, the other tripped a knife that marked the rod. Then the bullet clipped a far wire which turned off another electormagnet to trip another knife to mark the rod again. The distance between the two marks could be converted into milliseconds and then into velocity.

There were a variety of other designs using tuning forks, clock pendulums, spinning drums, etc. to time the bullet's flight over known distance, but I don't know how much the different ones were actually used.

Remington started using the Chronoscope vacuum tube oscillator counter chronograph in 1940 but the LeBoulenge stayed in use most places until the late 1940s. Hatcher has LeBoulenge data for 1947.

Velocity has been measured by ballistic pendulum. Fire a shot into a free-swinging bullet trap and measure the swing. Calculation yields momentum, taking account of trap and bullet weight allow figuring velocity.

There have been various rotating chronographs. Spin two cardboard discs several feet apart on a common axis at a known rpm. Fire a shot parallel to the axis, measure the angle between the holes in the discs and calculate the

 

[Stumpy]

Ball ammo spec's.

Cartridge,Ball,Cal.45 M1911,Engineering Drawing #B503,Ordnance Dept.U.S.A. dated Oct.13,1911 with revisions #31 4-17-43,#32 8-3-43 and #33 3-31-44. 820 +/- 25 ft. per sec. velocity at 25 1/2 feet from muzzle.

Stumpy

 

[MikeC]

I think we can all see where the +/- 25fps comes from. The fact that various automotive pioneers and JMB and others created the base for today with nothing more then brains, a slide rule and imagination really is mind blowing to me.

 

[chevyrulez1]

The "original" spec called for 230 gr. bullet to go 830 to 850 fps.

That's still the standard. The energy is about equivalent to the old .45 Colt round carried by the cavalry. So the standard didn't even change from the Peacemaker through 1985, about a 100 years. I don't know about 9mm.

Why would it be hotter? It's still shot through the very same guns.

Alot of the WW2 9mm ammo was actually loaded very hot because is was made to be fired in the German sub-machine guns. People have been known to destroy pistols using this ammo.

 

[guy sajer]

Alot of the WW2 9mm ammo was actually loaded very hot because is was made to be fired in the German sub-machine guns. People have been known to destroy pistols using this ammo.

I used to own an MP-40 and have fired a Sten . Both worked well with generic 9mm ammo . Not sure why they'd make the 9mm hotter ? You'd think we'd have heard of a large number of Luger's , P-38's and Hi Power's being kaboomed if they had a hotter load . About 15 yrs ago , I fired about 2,000 rds of WWII Canadian 9mm over a 1 month period through an Inglis HP . No apparent problems . I then proceeded to fire 3,500 rds of a very nasty Egyptian surplus over a 2 week period . Still kept tick'n

Not disputing your claim , and I've heard the same rumor , just never seen any evidence . I'd welcome any info you can share .