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· Registered
4 Posts
Discussion Starter · #1 ·
For lubrication, the owner's manual states "Apply 1 drop of functional lubricant ... to the holes of the breech block".

I'm staring at the breech block, and there are lots of holes. I don't want to overlube this thing and have it oozing oil everywhere.

There's obviously the firing pin hole (which I'm not dumping lube into).
2 small holes on the top (one in the middle, and one in the back).
One BIG hole in the side, exposing the side of the right guide rod.
3 holes on the underside: one about the size of a screwhole, a teeny one just aft of that, and the third at the back appears to be the same hole seen from the topside (it looks like it goes all the way through which begs the question why I would drip lube down it).

Can anyone confirm for me what the definition of "hole" is in the context of lubing the PS-90's breech block?

· Banned
326 Posts
Already been there on this issue - got it answered in the FN Q&A section a while back. The "holes" they refer to are on the sides of the block. One is round and you can see the guide rod through it and the other is the open area containing the other guide rod, spring and rate of fire stabilizer (the metal cylinder that moves back and forth).

I have found that if the guide rods are oiled on both ends by moving the breach block all the way in both directions, wiping the exposed rods and then cycling the assembly several times the areas in question get oiled by themselves.
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