• As some of you know, the old forum database was deleted by the previous administrator. I am attempting to paste any retrievable discussions back into this forum using the internet archive. It won't look pretty - but at least we can preserve some valuable information. Feel free to add to the discussions as these old posts are restored.

The mod. 38 Weapons


Staff member
A discussion on another topic got me interested in digging in a little deeper to the origins and history of the fucile corto mod. 38 and fucile mitragliatore mod. 38.

The need to develop a new cartridge offering better range and penetrating power than the 6.5x52 is well known. What is not as well known is that another design parameter was that the design must use as much as possible from the mod. 91 series to reduce the cost of fielding the new rifle. What this meant was except for reboring the M91 barrels to a larger caliber, the cartridge specifications must be the same or very similar to the existing 6.5mm cartridge. The plan was to modify up to 1 million M91 series weapons to the M38 standard, which would create a significant cost savings.

Changing the rifle would also mean changing the f.m. to the new cartridge. The design specification was that any changes needed by the Breda 30 would be limited to a new barrel.

The R.E. wanted to go to a cartridge somewhere between 7.5mm (the French) and 8mm (the German). Testing demonstrated that cartridge casing based on the 6.5mm but using a larger bullet didn’t provide the improved performance the army was seeking. The heavier bullet would require redesigning the casing, a change the R.E. was trying to avoid. The 6.5mm Carcano barrel could handle the increase in size to 8mm, but the receiver/chamber would need to be redesigned to accommodate the increase powder load. That would significantly increase the cost of replacing both the rifle and the f.m.

Further testing demonstrated that a caliber of 7.35mm could provide the desired improved performance without changes to the receiver/chamber except the required resizing of the throat. Shot-out M91 barrels could be rebored to 7.35 as enough metal was present to safely accommodate the change.

The adoption of the 7.35x51 cartridge in the f.m. Breda 30 (called the Breda mod. 39) was less successful. Because of the moving mass of the firing system in a machine gun, a new cartridge must be tailored to the characteristics of the weapon or the weapon tailored to the cartridge (see the Chauchat for similar problems when changing caliber). As the only change was the barrel, a machine-gun with issues using the 6.5mm cartridge had more issues with the 7.35mm cartridge.

So far, what I have written above is pretty straight forward. Now the challenge.

On what date was the decision made to stop production of the M38 series weapons? I have read anything from late 1939 to early 1940.

Does anyone have the document announcing the decision and the return to the 6.5mm cartridge?

How many (and which) units had already received the mod. 38 weapons? What happened to these weapons?

Did any frontline units still have M38 weapons on June 1940?

Can anyone add more to the story?

Pista! Jeff