Finnish .303 British?


#1

I had thought this Finnish box contained .303 British cartridges, but the shoulder is significantly less abrupt than the typical .303. Dimensions are:

bullet - .311"
neck - .337"
base - .456"
rim - .532"
case length - 2.181"
overall length - 2.996"

Also, the printed label says 7.7 m/m, while the 7,90 7,92 stamped on one side more closely equates to the actual diameter of the bullet. Can anyone confirm that these are indeed .303 British?


#2

Guy
On page 164 of the great book Suomalaiset Sotilaspatruunat 1918-1945
your cartridge is described as a .303 loaded by Valtion Patruunatehdas with a 176 grain(11.4 g )ball bullet headstamp VPT 38
I have this Book for sale at the next St-Louis show .

regards
gyrojet


#3

Thanks, Gyrojet.


#4

The actual bullet diameter of the .303 is .311", which is actually 7.9mm. .303" Is the bore diamter across the lands.

It is confusing that military calibres are usually named in this way, whereas sporting calibres use the bullet diameter.


#5

On the subject of the shoulder profile. The “softness” of the shoulder is just a wise precaution on the part of the ammunition maker against the possible variations in chamber dimensions likely to be encountered in .303 rifles.

Unlike a rimless case the shoulder on the .303 is not important for headspacing so it doesn’t matter.

You could write a book on .303 shoulders ( although it would be a very boring book). The first thing I do when I pick up a .303 case, fired or unfired, is look at the headstamp. The second is look at the shoulder.

Some fired cases are almost stepped like a Weatherby on the shoulder because the rifle makers have erred the other way when reaming the chambers. A precaution against oversize ammunition.

There were problems early in WW1 when rifles and ammunition came togeather from all over the world of troops on the battlefield being issued with .303 ammunition which wouldn’t fit in their particular rifles.
In all my years I have never encountered a factory .303 round that would not chamber but the problem still occours with reloads.

To offset the risk of this happening ammunition makers tend to make the ammuniton a bit on the small side (but still within the tolerances obviously) and most rifle chambers are a bit on the sloppy side.

This has a slightly detrimental effect on accuracy but in an infantry weapon it is not enough to worry about.


#6

The only time there was a problem with .303 ammo NOT chambering suitably was in 1915-16, when certain makers in Britain (“New factories”) made .303 ammo whose shoulder dimensions were not properly set and checked, and as a result, these cartridges Jammed (failed to chamber or failed to extract) from Canadian Ross Rifles (which rifles had pre-war “sporting rifle” toleranced chambers, and were only suited the the finer toleranced Canadian-made .303 ammo of peacetime)

The British and Canadians soon recognised this fact (soldiers in the field were actively “trying” different lots of ammo, and selected out the worst before going into battle (“M”., “N” and “J” were the worst offenders in this respect…).
The problem was the incorrect setting of the neck and shoulder die in the filling assembly machine, allowing for an over long head to shoulder length, causing the cartridge case to "jam " into the chamber. (not allowing the bolt to close). BY 1917, this problem with Ammo Factory QA had been overcome, but it ruined the reputation of the Ross Rifle for ever and they were withdrawn from trench duty by late 1916 (and replaced by SMLE )

It was so bad with Ross rifles that instructions to “Lengthen Chambers” with a reamer were passed out, as a temporary “fix” and “LC” was stamped on the chambers of all Ross Rifles so converted. At the same time, a reamer was also authorised for SMLE chambers, taking the head end of the chamber to .464; thus allowing for the Mud of the trenches and better extraction.

Otherwise, .303 cartridges are pretty well interchangeable with all SMLE type rifles, and the British cartridge was also interchangeable with the Japanese Type 87/T92 Naval MG cartridge (for Lewis and Vickers Guns, Boat and Aircraft) which the IJN copied from samples sent out by Kynoch in the 1920s.
After the fall of Singapore, the IJN used a lot of captured British and Australian and Indian made .303 in their own MGs.

regards,
Doc AV
AV Ballistics.


#7

sorry


#8

Addendum to previous Post.
Valtion Patruunatehdas ( later Valmet) was the major maker of .303 (“7,7”) ammo for the Finnish Airforce, whose British and Czech built aircraft of the 1920s and 30s were fitted with the premier Aircraft MGs of the period, the Lewis gun and the Aircooled Vickers (both the normal “Maxim type” and the Gas-Operated Model “K”)
Some aircraft bought from Italy had Fiat aircraft guns, also in 7,7mm (which was also the Italian standard air MG calibre at the time.)

After WW II a lot of this “.303” ammo was recycled to civilian use, both in Finland ( captured Soviet-captured-Baltic .303 rifles, largely used on Ladoga Front) and also sold thru Interarms, either as FMJ or converted to “Soft Points” by Lapua factory on behalf of Interarms.

regards,
Doc AV
AV Ballistics


#9

In well over 30 years of shooting 0,303" I’ve seen some rather remarkable fireformed cases ejected from Enfield rifles. I’ve seen the rifles fired until you could no longer use charger clips to re-load as the receiver was too hot to touch. I once lost the skin on my thumb when it stuck to the receiver wall. I’ve seen linseed oil boil out of the furniture and in one case a shooters cheek was covered with the stuff that had boiled out of the butt.I remember one No4 where the foresight blade dropped out because the barrel was so hot.

The converse of this is that I’ve only rarely seen an Enfield that wouldn’t chamber a round despite that sort of treatment. Sometimes the bolt gets a bit sticky as it gets hot but it’s almost always when ejecting a fired round rather when chambering an unfired one. The camming action of the opening bolt isn’t quite as efficient as it might have been. Problems in chambering cartridges are usually because the headspace is incorrect and that can be adjusted by unscrewing the bolt-head and replacing it with one of the right length.

It works because of the large tolerances built into the design.


#10

[quote=“DocAV”]The only time there was a problem with .303 ammo NOT chambering suitably was in 1915-16, when certain makers in Britain (“New factories”) made .303 ammo whose shoulder dimensions were not properly set and checked, and as a result, these cartridges Jammed (failed to chamber or failed to extract) from Canadian Ross Rifles (which rifles had pre-war “sporting rifle” toleranced chambers, and were only suited the the finer toleranced Canadian-made .303 ammo of peacetime)

The British and Canadians soon recognised this fact (soldiers in the field were actively “trying” different lots of ammo, and selected out the worst before going into battle (“M”., “N” and “J” were the worst offenders in this respect…).
The problem was the incorrect setting of the neck and shoulder die in the filling assembly machine, allowing for an over long head to shoulder length, causing the cartridge case to "jam " into the chamber. (not allowing the bolt to close). BY 1917, this problem with Ammo Factory QA had been overcome, but it ruined the reputation of the Ross Rifle for ever and they were withdrawn from trench duty by late 1916 (and replaced by SMLE )

It was so bad with Ross rifles that instructions to “Lengthen Chambers” with a reamer were passed out, as a temporary “fix” and “LC” was stamped on the chambers of all Ross Rifles so converted. At the same time, a reamer was also authorised for SMLE chambers, taking the head end of the chamber to .464; thus allowing for the Mud of the trenches and better extraction.

Otherwise, .303 cartridges are pretty well interchangeable with all SMLE type rifles, and the British cartridge was also interchangeable with the Japanese Type 87/T92 Naval MG cartridge (for Lewis and Vickers Guns, Boat and Aircraft) which the IJN copied from samples sent out by Kynoch in the 1920s.
After the fall of Singapore, the IJN used a lot of captured British and Australian and Indian made .303 in their own MGs.

regards,
Doc AV
AV Ballistics.[/quote]

This is not quite the full story. Although there were problems with some British ammo with regard to gauging, particularly that from Birmingham Metals and Munitions, the real problem lay with the manufacture of the Ross rifle.

The original Ross Mark III rifles were chambered with a head diameter of .460" (and some were found to be .458") which was lower that the British low limit of .462". Canadian ammunition was also manufactured to this lower tolerance. Quite how the Canadians came to manufacture rifles and thd ammunition that were different from the Imperial standard is not known.

Another problem was that Ross gauged the chambers before assembly and not after breeching up. If the barrels were torqued too tightly in the receivers this compressed the chambers even further.

When this was discovered in 1915 the chambers were reamed to .462" and the chambers stamped with an “N”. This was done from 9th July to 15th August 1915 when the chamber was again changed to .464". Rifles with the larger chamber were stamped with an “E” for enlarged chamber.

The rifles that had come to the UK with the CEF still had the smaller chamber so Lt.Col. Harkom (an ex-Enfield apprentice) was sent from canada to the UK to sort matters out. He set up the Canadian Ordnance Depot at Ashford in Kent and reamed the chambers to .464", stamping them with “LC” for Large Chamber, not Long Chamber.

He also hardened the bolts and bolt stops, but that is another story.

Pictures show the three different chamber stamps.

Regards
TonyE