Maxim MG08 O-Ring kit


I own 3 different Maxims and when combined with 6 different muzzle nuts/boosters I only have 1 combo that fits perfect. By fits perfect I mean, parts installed, muzzle nut tight against the waterjacket and everything fits perfect. Odds are that will not be the case when you install these pieces. Between my MGs and muzzle nuts there is an .080 variance in how the parts fit.

To install the Maxim O-ring and spacer you need:


Brass Spacer


Teflon tape.


Step 1. Get your MG08 and remove the feed block, fusee assembly and the lock. The barrel and recoil plates should move freely. Put all the moving parts in the forward position.

Step 2. Wrap a bunch of teflon tape around the threads of your muzzle nut. There needs to be enough tension that it takes effort to unscrew once installed.

Step 3. Grease the barrel where the o-ring makes contact and install the O-ring.

Step 4. Install the brass spacer with the flat end facing out.

Step 5. Install the muzzle device until you feel it get tight against the brass spacer.

Step 6. Pick up the Maxim and rest it on the grips with the muzzle pointed up.

Step 7. Put one hand at the bottom of the cocking lever, and with the other hand unscrew the muzzle nut until the barrel starts to slide out. At that point you are done. The muzzle nut doesn’t have to be tight against the waterjacket, it just needs enough tension from the teflon tape to stay in place. The o-ring seal with basically no tension will keep the water from leaking.
Step 8. Assemble the weapon and pack up for your trip to the range.

If you want to make the spacer a prefect fit with your MG, grab a file, some emery paper, or hold it on a belt sander. You may only need to remove .015, or as much as .050. But hey, if you didn’t enjoy having to tinker with your Machine Guns, you’d be shooting a Browning and not a Maxim 🙂

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Each kit is one brass spacer and 5 O-rings for Maxim MG08 and Argentine World Standard  which eliminate the need for packing material in the muzzle gland.

This kit will NOT fit the Russian Maxims.

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