AllOutdoor Field Strip: FN Model 1900 Great Grandfather to Modern Pistols

   12.17.20

AllOutdoor Field Strip: FN Model 1900 Great Grandfather to Modern Pistols

The FN 1900 conceived from John Moses Browning’s brain is the footprint for the modern-day handgun. It had the greatest and most notable innovation in that its action was straight blowback with a slide! It was forward-thinking enough to not only have a cocking indicator, but it would also lock open on empty. Nearly 725,000 guns and 120 years later I have in my possession a piece of firearms history.

With the launch of our Curious Relics segment and the first two articles featuring this very same gun I figured it would be a cool chance to show you guys how it disassembles and functions. I will try and link to the first article here.

The big thing to mention is that this is more of a general disassembly article rather than a field strip since involving the need for a tool and loose screws out in the field kind of disqualifies it. I do not recommend taking your gun apart without the proper experience. As simple as this all is it would be ill-advised should you end up hurting yourself or others or at the very least your very old and valuable firearm. With that said, let’s hop down the rabbit hole!

AllOutdoor Field Strip: FN 1900

1. First thing is first! Practice all the rules of gun safety. When disassembling a firearm you should always wear safety glasses due to multiple parts being under spring tension. Triple check that the firearm is unloaded. Check the chamber, magazine, and the area in between. All set? Let us jump right into it!

FN 1900

2. The first step in disassembling the FN 1900 is to remove the magazine. To do that you push the heel release toward the direction of the muzzle.

FN 1900

3. The magazines for these guns are very tight, but if properly lubricated the magazine should be under minor spring tension and push out about half an inch. From there pull out the magazine.

FN 1900

4. After removing the magazine set it aside somewhere safe since these are old, fragile, and hard to come by. As of now if the FN 1900 is cocked you will see the indicator flush with the rear sight groove.

FN 1900

5. Pull the trigger (this is why it is important to make sure the gun is not loaded) to essentially un-cock the mechanism. The cocking indicator should block the view of the rear sight to the front sight.

FN 1900

6. From here you are in an un-cocked position and can now remove the two screws securing the slide to the breech block/bolt. Remember when removing screws to use the proper screwdriver. The ideal size is something just barely a smaller length than the long axis of the valley in the screw head. Too big will result in harming the firearm and too small will result in harming the screws.

FN 1900

7. Take care to put these screws in a safe place for the same reason as the magazine and every part to follow.

FN 1900

8. Now the slide is able to come off the frame and mainspring guide. Pull towards the front and if met with some sort of resistance make sure you followed the previous steps correctly.FN 1900

9. Sometimes the slide is so tightly fitted that sliding the slide to the rear and letting it run forward will aid in freeing it from the frame.

FN 1900

10. Now that the slide is off, take time to examine how the recoil spring and guide are held. This is important as I mentioned earlier in that you should avoid harm to you or your very old firearm. Note that the recoil spring should look goofy like in the photo below.

FN 1900

11. In the photo below I am pointing at where the spring is held captive and is under some spring pressure.

FN 1900

12. At the spot pointed to above, grasp the spring and gently pull forward to the muzzle and lift out of the capture point. The spring itself should be held by the button on the end and if not you would have already found that out.

FN 1900

13. At this point the breech block should be able to be pushed to the rear of the frame.

FN 1900

14. The breech block should slide out the back of the frame unimpeded unless excessively dirty.

FN 1900

15. Now the “field strip” should be complete! Make sure that you still have all your parts. In order to reassemble just do the reverse of what I just went through and take the same amount of consideration and care while doing it.

FN 1900

When disassembled this would be the best time to put a good quality lube on the rails of the breech block, where the breech block meets the slide and even a drop on the barrel (not in). I would recommend putting a moderate amount of grease on the recoil spring and in the recess where the recoil spring sits in the slide. After reassembly un-cock it so tension is not unnecessarily held anywhere and put some oil on a rag generously and wipe down your gun. All of these things are great ways to prolong the life of a gun that has lived long after its time. Keep it that way! In closing, thank you to anyone who tuned in and followed along! I hope this was helpful and educational. Please always remember to practice proper gun safety and to be mindful of parts so that you do not lose any. Safe and happy field stripping!

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