The Lahti m/40 pistol is a cinch to strip but a bit of a hassle to fully disassemble. Due to some rivets and roll pins we couldn’t quite go all the way with the one we had on loan but what we did get away with should be more than enough.
Before we begin C&Rsenal would like to thank East Coast Guns of Summerville, SC, for donating this piece for the article. Make sure to thank them yourself if you stop in.
The Field Strip
- Locking Block
- Takedown Catch
3. Turn the Takedown Catch 90 degrees clockwise.
Your Lahti m/40 is now field stripped. Reassembly is just the reverse. The Locking Block has a front and back, there should be an arrow stamped on the bottom to specify. Point this at the front of the gun.
CAUTION The Swedish Lahti is a fairly complicated pistol with some small parts. Most of the assembly is held by pins and they may or may not be flared depending on who has used the gun before. Moreover, some pieces are riveted or heavily flared in place and should not be removed unless necessary for replacement. Our pistol was a donor from the good folks at East Coast Guns of Summerville, SC, so we skipped a few risky steps. Our apologies for those pictures that will be missing.
- Front Sight
- Accelerator Retainer Spring
- Accelerator Retainer
- Firing Pin
- Firing Pin Spring
- Firing Pin Cross-pin
- Recoil Spring
- Trigger Bar Pin
- Trigger Bar
- Takedown Catch Spring
- Takedown Catch
- Trigger Pin
- Magazine Catch
- Magazine Catch Spring
- Hammer Spring and Plunger
- Hammer Pin
- Sear and Spring
- Sear Pin
- Grip Screw
- Safety Lever
- Magazine Catch Pin
- Trigger Spring
- Locking Block
3. Tip out the Firing Pin and Firing Pin Spring. You may now set aside the Bolt and its components.
5. Remove the Accelerator by pulling it out and towards the back of the Mantle. CAUTION The Accelerator Retainer is under pressure and may be lost. Remove slowly and carefully to keep it under control.
6. Use a small punch or screwdriver to fish out the Accelerator Retainer Spring.
7. The Ejector is very sensitive and should only be removed if necessary. Look inside the Mantle and depress the rear tab of the Ejector. Then push it forward until it clears its recess. You may now remove it from the outside of the Mantle. You may also set aside the Mantle and its components now.
9. Carefully pry the Safety Lever as you turn it rearward. At the rear of its intended sweep there is a stud. Lift it just over this stud.
15. Now remove the Hammer. Step 14 helped get around the permanently attached Recoil Spring easier.
17. Remove the Hammer Spring and Plunger.
20. You may remove the Takedown Catch Spring by placing a punch in the hole located at the front of the Frame and driving it rearward.
21. The Trigger Bar Pin is usually riveted or heavily flared into place. It is not recommended that you remove this component unless necessary. If so, drift it out of place. Then remove the Trigger Bar rearward and proceed to step 22.
22. This step is only necessary if you opted for step 21. Drift out the Trigger Pin and remove the Trigger by pulling it down and rotating it out.
24. The Hold Open Latch is secured by a delicate spring. Remove only if necessary. We have not opted to do so on our loaner and can only provide written help. If you need to remove it read steps 25 and 26 else skip to 27.
25. Use a small tool to push the rear of the Hold Open Latch Spring up. Then lift it out of place.
26. Turn the Hold Open Latch up to about 90 degrees and then move it towards the right of the gun to remove.
27. The Front Sight should not be removed if unnecessary. If so, drift it out of place left or right.
Your Lahti m/40 is now stripped. Reassembly is just the reverse. We recommend using a small bit of rolled paper or wood skewer to realign the Magazine Catch and Magazine Catch Spring as you place them in the Frame.