fn 1903 caliber

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Not sure if this question should go into milsurp but I'll try here first...

I have a FN 1903 Swedish contract (not Husqvarna built). How do I check what caliber it is? It could be the original 9mm Br Long or converted to 380 acp...
 
the barrel should have markings on it if it has been converted. any pics? does the barrel look like a replacement?
 
No markings on the barrel. I've never seen a replacement - it doesn't look new, but I have some 100 year old guns that look newer...

29lmgs2.jpg
 
The 9mm Browning Long case is 3mm longer, and the rim is a lot larger, compared to 380. You should be able to tell by sliding a case into the chamber which one it is that you have.
 
I'm not sure I have any... definitely not the 9mm Br Long, a few of 380 possibly in the bag of odd brass...

Would the barrel have a defined inlet for the rim if 9 mm Br Long?
 
I would say the size of the 380 rim versus the size of the opening in the breach face might be a way to tell them apart as well - but I'm not very familiar with the 1903.
 
If its Swedish contract, then it should be 9mm browning long as Sweden used 9mm browning long for its military. 380 is aftermarket conversion so to speak and should be marked on the frame and barrel somewhere. There is one for sale on ee with 380 markings, may be pm the owner, who can shed some light on his markings of 380 conversion?.
 
I'm impressed that someone thought it was worthwhile to make entirely new barrels - machining seems complicated with that locking mechanism... I would not have been surprised if they'd converted original barrels.

gewehr, thanks for the pointer (that ad is very hard to find btw) - the pictures there are quite clear and indicate mine is in 9mm br Long

JTF, your pic is at a guess of a mod 1922 not 1903... but what you say makes sense.

Thanks everyone!
 
i was just giving you an example of a converted gun. i don't have a 1903. you can see the new converted barrels are marked clear and proof tested. the 9mm marking could be confusing but you know it has been converted.
 
A .380 auto round will drop into the barrel way past the feed ramp on an original barrel, where the 9mm Br Long round will be almost flush with the face of the barrel. As well, the barrel is recessed for the rim.
My gun is a Husky with matching serial numbers on frame and barrel, but no caliber marked on either. Hope this helps. John
 
.380 empty case falls right in and since 380 is supposed to headspace on the case mouth, I'd say evidence is good it's in 9mm Br Long. But this is not an original barrel either. There's a fn 1903 swedish contract on gunborker right now with excellent pictures (search for fn 1903 swedish). My barrel is not serialized to the gun and does not have have the Liege proofmarks. Also of note is that while that gun's barrel is serialized to the gun, still carries the Liege proofmarks and not caliber marked, it is in .380 via a 'chamber spacer'...

So looks like the only definitive way to tell the caliber of these is to try to fit the ammo in. So far it looks like tradex has the 9mm br Long in stock. Or perhaps I'll be able to find a 380 barrel somewhere.

4liuyb.jpg
 
Why do you want a .380?

No real rational reason except that I can :) It's just an extra barrel, so why not?

FYI, I used loaded cartridges in post #12, not fired brass. Also look for an undercut accommodating the rim of a 9 BrLg.

Mine has the undercut, but I would expect to see an undercut in a barrel that was converted with a bushing - like the one on gunborker.

I don't have any loaded ammunition in either caliber. I think I'll just order a couple boxes of each and then start reloading if I ever want more (I'll have a gun in 380 soon anyway so it's not like it'll go to waste).
 
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Well, if anyone is curious I have some answers.

I was able to get my hands on a. 380 barrel (and some other parts) . It came from a Husqvarna manufactured pistol (by the matching slide) It has Swedish proofs (and a serial) but no caliber markings.

My original barrel has no proofs (and no serial) and no caliber markings also. It comes from a FN manufactured pistol and is likely an armoury replacement.

If I shine a light into the chamber of the 380 barrel, I can see a little ring insert to support the shorter cartridge at the mouth. That seems to be the only change made to convert an originally 9 br long barrel to 9mm short.

The 9mm barrel has a recess for the rim. 380 does not. This is surprising for a converted barrel. A reversed 9 br long cartridge does not fit! Makes me wonder if they used unchambered barrels to convert? Very confusing...

So the only definite way to tell which caliber the gun uses is to use a loaded cartridge. 380 will drop too deep into a 9 br long barrel. The other will stick out. The proper cartridge will fit flush.

Note that if the 380 barrel is actually a converted barrel, the 380 bullet will fit looser into the rifling than the original 9 br long bullet. It will also have a longer jump to the rifling.
 
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