Gunboards Forums banner

1 - 2 of 2 Posts

·
Registered
Joined
·
2,734 Posts
Discussion Starter #1
A repost of an informative older thread, slightly edited:

Andy_P
Posted - 03/19/2005 : 12:16:58 PM
--------------------------------------------------------------------------------

From the Sticky by 1886lebel "Berthier Modifications: "Balle N's bullet was slightly larger in diameter (.326) to both Balle M or D (.323) so the cartridge cases neck had to be increased to hold this bullet."

I have seven Berthiers - five marked "N", two not. All slug out to 0.327+ Hence my desire to have a few things clarified:

- did firearms made for Balle D and M have a bore diameter of 0.323", and for Balle N 0.326", or were all Berthiers of the 8x50R persuasion 0.326"

- if both, did Balle D and M use a 0.323" bullet in a 0.326" bore?

I have searched this and other sites and have been greeted with strong and opposing opinions on the subject!

Essentially what EXACTLY is the difference in the Balle D, M and N rounds and the bores and chambers for the guns designed for them?

I am already making 8x50R brass from 348 Winchester using the Lee dies set and have shot it in a Turkish Forestry Carbine (Marked for Balle N) with "success". Can I do the same for the non-Balle N firearms as long as I use the correct diameter bullets (0.323" for non-Balle N, and 0.326" for Balle N)? My gut feel based on my uncertain understanding is that using 0.326" bullets in a non-Balle N chamber (even with a 0.327" bore) will cause neck clearance (tension) problems.



kelt
France
2315 Posts
Posted - 03/19/2005 : 12:59:01 PM
--------------------------------------------------------------------------------

The modification in dimensions between the D and N bullet is the location of the maximum diameter, but the maximum diameter of the bullets are identical.

The D bullet has the maximum diameter before the crimping groove, and outside of the case.

The N Bullet has the same maximum diameter as the D bullet, but it is located after the crimping groove and inside the collet, hence the N modification of the chamber at the collet location.

If you look it up here this topic has been discussed already and drawings with dimensions of the bullets posted.

kelt



DocAV
Australia
3278 Posts
Posted - 03/20/2005 : 6:36:26 PM
--------------------------------------------------------------------------------

Again, confusion about European "8" mm bore/groove relationships.

back in the 1880s, the design of both jacketed bullets and use of smokeless powders was at a critical prototype stage. many nations had serious research going on into the relationship. Things like quality of barrel steel (made for Black powder and lead only bullets) what materials to use for bullet jackets, how hard to amke the lead core, how much friction to allow between jacket and bore, etc, how much allowance for Bore fouling, and so on.

Most of the nations using a Nominal "8"mm actually had a .315 inch (===8.0mm) Bore. Rifling depth was another matter, depending on the Bullet type. Most nations, (France, Austro-Hungary, Portugal) used the Swiss developed "Deep rifling/undersized cylindrical bullet" relationship, allowing the upset of the open base of the Bullet by the intense pressure of smokeless powder to obturate the bore, whilst the greater part of the cylindrical bullet jacket just barely engaged the rifling, reducing the Wear and friction of the lands by the (mostly steel) jackets. Nickel or Curponickel plating of the jackets tendedto rub off (metal fouling) and fill up the generous grooves, to be removed by vigourous brushing after use.

So the "8mm" bullets used in the Lebel Mannlicher, and other rifles
had a .323-326 diameter bullet, in a .315 Bore with .326-329 diameter bores, depending on national requirements.

By 1898, the French had adopted both a clip magazine fed carbine/short rifle (the M1890/1892) and a MachineGun (Hotchkiss M1897), which did not require a cylindrical bullet (the lebel was atube loader, and was, de riguer, a Flat point bullet user at that time ( "Balle M").
Desaleux, to the STA, designed a spirepont Boattail bullet of "bronze"( actually 90/10 Gilding metal) which was machine turned from rod. This the the famous "Balle D" which served from 1898 through to WW II; ( even if partly supplanted by"Balle N" from 1932 onwards)
Being a "Boat tail", it could NOT obturate by "Upset" so the diameter foward of the crimping cannelure was upped to .326 ( French groove diameter) a bit like an artillery shelldriving band.
Due to the generousfree bore in "Balle M" chambered weapons, there was no need to relieve necks or throats to accept the slightly oversized projectile.

The use of Balle D in Lebels was solved by adding a "point lodgement Groove" in the base of the cartridge case, so that because of the double taper case geometry, it would sit "point down" in the magazine tube, and the point of the spitzer would not "slip up" into the primer cup.

In the 1930s, many nations upgraded their 1880s ammo designs to a Boat tail projectile, the major countrise being the Descendants of the Austro-Hungarian Empire and other users of Mannlicher rifles.
The Austrians, mindfull, in part , of the boattail problem with "bore upset", went straight to a .329 diameter Boat tail, so as to completely obturate their .315/.329 M95 bores (the "S" cartridge, ( 8x56R) or "M30 8mm "S"); Hungary followed closely (31M) and Bulgaria soon after ( 1936, "8mm S Mannlichera").
The French in the late 20s early 30s, were upgrading their armoury, and saw these Austrian developments, and developed a 230 grain FMJBT with lead core; different from the earlier balle D, this could not be "turned" with a driving banddiameter in front of the Crimping groove, so the major diameter was placed behind the groove ( by Bullet manufacture/Swaging), resulting an a larger Outside neck diameter. As this could cause increased pressures in Older "Lebel"Rifles, the chambers were neck relieved "N Chambered" to allow for this extra diameter.

Anyway, today for a serious Milsurp collector/Shooter, this is a Moot Point, as there is virtually No shootable "N" Ball ammo about in the world, Most being Hotchkiss strip packed, with dead primers.
If one is keen enough to replace the Special double cup berdan primers with new, Noncorrosive, single cup modern .250 berdan primers, and re-assemble the "balle N" Loading, then I would say, yes by all means. Otherwise, handloading using .348 [email protected] reformed cases, one uses Flat base FMJs to obturate well, or cast lead. Remember, Lebels are Over 100 years Old, Berthiers in their 80s and 90s, And as For Hotchkisses, how many have (NFA approved) rock and rolling Hotchkisses out there?

Hope this short quasi scientific dissertation helps people understand the intricacies of European ammo and its relationship to the rifles it can be fired in.

Regards, Doc AV
AV Ballistics



kelt
Posted - 03/23/2005 : 5:20:28 PM
--------------------------------------------------------------------------------
DocAV,

The Lebel was adopted in 1886 and was the very first infantry rifle using a small bore smokless powder ammunition.

The solid brass D bullet was designed for the Lebel rifle and adopted in 1898 specifically to improve its ballistic, the original bullet being obsolete after more than 10 years of constant progress on powders/ballistics.

The D bullet of 1898 and the N bullet of 1932 have the same outside diameter of 8,30mm

The 1932N MG bullet is an evolution of the 1917 MG bullet, the french ballistic experts did not wait until the mid 1930 and the Austrian developpement, at the time the 8x50mm ammo was being phased out in favor of the new caliber adopted in 1924 from a 1900 design (7x58mm STA used in the very first FSA the Meunier A6 of 1910) and modified in 29 as the 7,5x54mm.

I have noticed that very little of the experimentation and developpement on small arms and ammunitions carried out in France from 1880 to 1940 is known, and that quite a few misconceptions are being kept alive from book to book.

kelt



DocAV
Australia
3278 Posts
Posted - 03/23/2005 : 8:58:03 PM
--------------------------------------------------------------------------------

Whilst the Balle D may have been designed to "Improve" the ballistics of the M86/93, it was in the modified M97 Hotchkiss that the improvements really were evident.(and in the subsequent M1914 )

My mistakes in the Bullet diameters ("8,30") do not detract from the fact that manufacturing methods (Turning versus Swaging) did affect where the "8,30" "driving band" diameter was placed; and this affected the neck diameter after loading.(the balle "N") and so resulting in the larger "N" chamber neck.

As you said, a lot of French information regarding ammunition development is either lost or buried at the old MAC facility Archives...But there was,a lot of interchange (official and not)of information regarding design;
And I am quite aware of the STA experiments on the various 7mm cartridges...one designwas eventually taken up by Sharpe & Hart, after WW II (the 7x61 S&H, made by Norma) virtually a copy of the 7x60 STA No 8? cartridge of 1902-04?

If you have a STA rifle, then S&H cases may be a good source of formable cases for it......WOL (wishing out loud).

regards, et Bonnes Paques...
Doc AV
 

·
Registered
Joined
·
3,061 Posts
The industrial manufacturing process for the D bullet was by swagging and not by turning.

The early production for the developpment of the best bullet profile was done by turning, but once the design was approved, the bullets were swagged, and the location of the maximum diameter did not matter at all.

The material, Brass 90/10 would have been a poor choice for an industrial fabrication by turning, but was a good choice for swagging.
 
1 - 2 of 2 Posts
Top