9mm Ammo OAL...

[Johnny C. Kitchens]

There has been quite few discussions on the Over All Length (OAL) of 9mm ammo for the Luger. I decided to measure as many 9mm Luger factory loads as I could, and I made this chart for reference. As I get more I'll add them to it.

Notice how Winchester leans toward 1.06 with loads using bullets lighter than 147gr...

[Doubs]

Johnny, thanks for the information. Unless you have an extra 1 in the 147gr Black Talon listed last, all loads are shorter than German military Luger rounds which have been reported at 1.175" OAL.

[Vlim]

Hi,

Nice list, if you can get a separate list with overall case length, that would be handy too.

[Frank]

Hi Johnny C., nice chart!!

More info, if you want it!! The data are my measurements, except the Lyman and Speer Recommendations

Original (about 88 gr) Cartridge Data Pistolenpatrone 1944 OAL = 1.170
Recommended Lyman Length = 1.169
123 gr Syntox (Geco) Cartridge Length = 1.157
Mejia Cartridge Length = 1.120
Recommended Speer Length = 1.100

[Johnny C. Kitchens]

Thanks, I'll add those to my chart. The Black Talon is 1.1175. Looks like I'm going to have to try some of these longer OAL in my reloads. My byf42 seems to like the 1.06 to 1.08 range of lengths. A little experimenting will be fun...

[Doubs]

"Recommended Lyman Length = 1.169"

More than 35 years ago I bought a rough-looking 1916 DWM Luger for $55 from a pawn shop in Tacoma, Washington. I was stationed at McChord AFB at the time and shot in the pistol club facility. I fired hundreds of rounds of Lyman 356402 mold cast bullets (120 grain, truncated cone) through that Luger and don't recall a single malfunction. I wasn't sophisticated enough in those days to worry about things like OAL..... I just loaded them with 6.0 grains of Unique and shot them. It was extremely reliable and I regret ever selling it.

[Sieger]

Doubs:

While on vacation in Florida a few months ago, I did some serious measuring of original German Army ammunition as well as Pre Great War Commercial ammo. I'll post those here when I get a little more free time.

From what I know of the German ammo, the American ammo you have listed above is mostly too short for reliable feeding.

Sieger

[Johnny C. Kitchens]

I've noticed that different bullet shapes seem to work with different OAL. I was experimenting recently with Remington 102gr bullets and settled on a 1.065 OAL. Testing 124gr Remington bullets, I settled on a 1.105 OAL as a working length for my Luger. I'm going to test some other lengths and bullet designs and see what I come up with. One fun reason to get into reloading, experimenting...

[Steve Richards]

I just measured some Sellier & Bellot 115gr (Czech Republic) and out of 16 rounds I got the following:
1.154 - 1
1.155 - 2
1.156 - 4
1.157 - 6
1.158 - 3
for an average of 1.1565
Just some more info to add to your list.

Steve

[Doubs]

Sieger, your measurements will be very interesting to see. Is any of the WW1 ammo of the truncated cone type?

[Sieger]

Hi All:

OALs of German Military & Commercial; and Pre WWII American Commercial 9MM Ammo as manufactured through 1945 (By Head Stamp):

Note: For MM to Inches Multiply By .03937

German Military and Commercial:

DWM/K/11/11 TC 29.2MM or 1.1496 inch.
DWM/K/12/17 RN 29.6MM or 1.1653 inch.
St*/12/42/VB RN 29.6MM
Ge/17/D/S RN 29.6MM
S/1/18 RN 29.7MM or 1.1692 inch.
DWM/K/11/11 TCHP 29.13MM
St*/1/42/dou RN 29.6MM

Pre WWII American Commercial:

UMC/9mm Luger TC 29.06-29.55MM
WRA/9mm TC 28.88-28.91MM
WRA Co/9mm Luger Auto TCHP 29.13-29.2MM
WRA/9mm LugeR TC 29.04MM
Peters/9mm Luger TC 28.62MM
Western 9mm Luger TC 29.00-29.22MM
Rem-UMC/9MM Luger TCHP 29.19MM

About 30 years ago, I developed OALs that would shoot, without jaming, through my 9MM Lugers with their original magazines:

TC 29.2MM or 1.15 inch. (rounded)
RN 29.8MM or 1.175 inch. (rounded)

Strangely, in later years when I picked up one of the DWM Owners Manuals (Repo) it gave the following OALs:

9MM TC 29.0MM or 1.1417 inch.
7.65 RN 29.8MM or 1.1732 inch.

The German 1906 Navy Manual lists the following OAL for the 9MM:

9MM TC 29.2MM or 1.1496 inch.

Over the years, I have found the OAL measurement to be absolutely critical to the proper functioning of a Luger, and have spent quite a bit of time developing proper OALs for each bullet type I handload.

Of special note is the fact that all Luger Magazines are not created equally!!

Though the original Luger Magazines had an interior length of 27MM, the new Mec-Gar Magazines seem to be set up to properly handle shorter ammo. I'll do some detailed testing of these magazines on my next trip to Florida.

Gentlemen, your comments.

Sieger

[Johnny C. Kitchens]

The only bad thing I can say about the Mec-Gar, is that the spring is weaker than any of the other magazines I have. I've noticed it fails to activate the hold open device most of the time on my byf42. I'm thinking that one of those Wolfe springs may improve things a lot...

[Sieger]

</font><blockquote><font size="1" face="Verdana,Tahoma,Arial,Helvetica,Geneva">quote:</font><hr /><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Originally posted by Johnny C. Kitchens:
<strong>The only bad thing I can say about the Mec-Gar, is that the spring is weaker than any of the other magazines I have. I've noticed it fails to activate the hold open device most of the time on my byf42. I'm thinking that one of those Wolfe springs may improve things a lot...</strong></font><hr /></blockquote><font size="2" face="Verdana,Tahoma,Arial,Helvetica,Geneva">Johny:

My Mec-Gar magazines are new, and seem to have very stiff springs.

I was quite happy to findout that they seem to work better (with the shorter stuff anyway) through both my 1917 DWM and my byf 41.

For a spring replacement, contact Thor, as he has just replaced a weak spring I had in my original 1917 magazine. After 87 years, things do wear out you know.

Sieger

[G.T.]

Gentlemen! I currently offer a coil magazine spring that far exceeds the factory MEC-GAR springs, and any aftermarked spring now available in, every respect... it is equal to or in most cases, better then any original springs, in strength, consistance, and resistance to set... these springs were designed by me, tested by me, and made to exacting specs, with the very best material available for their type... I stopped production three times, because extensive testing showed a need for change... it cost me twice what a normal run of springs would, on material alone.... I sell them for $5 each, and have a quantity price available! I would certainly appreciate it if you would give them a try! best to you all, til...lat'r....GT

[Thor]

GT, I have recently bought around a dozen Luger mag springs, some coil, some rectangle from Wolff. When I need some more I will contact you first. I assume you dont have of the rectangular zigzap ones yet? The one thing I noticed with the Wolff coil springs is the spring is a little bigger in diameter and when you slip it over the top plunger it makes the plunger/spring assembly DRAG inside the tube. What can you tell me about your spring in this regard??? Thanks GT!!!

[G.T.]

Hi Ted! Glad you asked!! Great question! I'll try to give you a rundown on whats occuring during the (sometimes really short!) life cycle on these spring types!
First of all they all start pretty much the same, as far as free length, wire diameter, and number of coils. You generally can change the compression rate by changing the wire dia. or the number of coils over a given length. The original designers have this pretty much nailed down in their specs, and a mint condition original spring is usually correctly matched to the specific purpose it was designed for...
The problem is, many, many, if not most of the original springs have been clipped to try to solve perceived mag. problems, related to feeding and function problems in the Luger pistol over the last 90 years! Also, there is a slight variance between many of the original springs in wire dia.. So some mag's springs are soft on compression, and some are stiff! BUT, They all (original springs) generally exhibit a fairly consistant, high quality material, and here is where the REAL mag. function problems start!
The area in the magazine shell that is designed to contain the spring during it's compression cycle is approx. .450" to .460" in its max. capacity.. The spring design calls for a free length dia. from between .437 min. to around .440" to .445 max.... this allows anywhere form .015" to .020" clearance for the spring dia. gain during the spring cycle.... sounds fair enough... .015" usually is a pretty large tolarance for any moving assembly... Well, heres what happens... when you compress a NEW spring, two thing happen, the spring free length becomes shorter, and the coil diameter becomes larger... this happens in most all, if not all springs that are constantly and repeatedly taken to their design limits, this is called "taking a set"... A high quality spring will take a set, "break in" and then will change very little over its life span, generally, before it digresses much further, it'll break, after thousands, if not tens of thousands, of full compression cycles! In competitive events of all kinds, involving machines that use springs, generally, you use a spring that has already taken a set, shim it to its original starting pressure and compete that way. So your not trying to tune a constantly changing component And, as in the situation concerning ALL after market mag. springs, they continue to grow all the way thru there SHORT life cycle! So every time you fully compress the mag. spring to get your full capacity, it is continually growing in dia, and becoming shorter, and weaker! As the spring wire quality is not up to the task at hand! So... it is usually within 20 to 30 full compressions, that the spring has grown to a overall dia. that totally uses up the designed tolarance designed into the assembly and you have severe spring drag, AND it is still getting worse as the spring continues to digrade! No end to the set!
When I designed my new springs, I took all of these factors into consideration! and I tweaked the original specs to accomplish the design parameters that I felt would be satisfactory...(no small feat in itself! These guys were pretty sharp!) and one of the goals, right from the start, was to eliminate spring drag!
So, I did three very critical things that all the other manufactures have either neglected or ignored... And they are,
1)I designed my springs to come into final spec. as they take a set! After 20 to 30 full cycles, my springs take a full set at approx. .437" THEN, THEY DON'T CHANGE! This is the min. free length dia. design spec,. that the print calls for!
2) I TESTED! I took all the springs and mags that I could get my grubby little paws on, and literally compressed them to failure... I then devoloped my own design parameters...that eliminated all the problems that arise from an inadaquate design....
3) I would ony accept the VERY BEST material available.... The spring company was set to run my springs on three seperate occasions. They would FED X overnight some samples to me, and I would spend all night testing the pre-production samples, with the intention of running the whole lot in the morning... THREE times, I rejectect the samples, which started us on a quest to find an adequate spring material that met with my standards! This cost me a $100 bucks each time they set up! Not to mention each time I made a change, the material cost doubled, as the quality improved!
Thats about it, when the new springs arrived, and after a short test, I was elated!! the springs were exactly as I had hoped! As good as, or better then, original! Now, "build a better mouse trap and the world will beat a path to you door!" Not Hardly! I have had very little interest in my new product! They are the very best, I know they are, and, I appreciate your question, letting me explain the "hows" and "whys" of my design philosophy! Best to you Ted, I look forward to filling your next spring order requirments! til...lat'r....GT <img border="0" alt="[jumper]" title="" src="graemlins/jumper.gif" />

[Johnny C. Kitchens]

OK, how do I get one from you? Where and total amount needed. Are the two pins near the bottom all I need to remove to get inside the Mec-Gar magazine???

[G.T.]

Hi Johnny! Thanks for the Inquiry! My address is: G.T. Specialties
316 West Straford Drive
Chandler, AZ 85225

and my email is: gctomeks@msn.com

Drop me an email, or, send me $5, and I'll zing one out to you Johnny! Til...lat'r....GT

BTW, The MEG-GAR mag. has two press fit retaining pins.... you have to have the shell well supported, with the pin over a small hole, to drive out the pins! but after that, it comes apart easily! Best of Luck!

[Sieger]

Hi Again:

As Alfred Hitchcock use to say, "now a word from our sponsor".

Johnny, OAL is most important for the proper fuction of a Luger; because the cartridges ride up the front and rear of the magazine, not just straight up like in a 1911 or a P-38.

At this short length, the noses of the bullets are probably slanted downward and will, eventually, jam the pistol.

You may wish to try some at 1.175 to see if the cartridges ride up nice and evenly.

Sieger

[Doubs]

Sieger, please check your private messages.

Doubs