The Marstar METRIC GAS LOCK front sights are worth the money.
Gas locks, and particularly the GLFS are NOT trivial ...
notice that when you turn over Marstar's gas lock front sight, the thread is indexed differently. This means you can get TWO different gas assembly lockups with one GLFS ...
and one of them should index correctly [ 4 o clock plus some rubber hammer time ] for your particular gas assembly.
This might save you a shim pack.
PLUS,
the GAS LOCKS should be surface ground perfectly flat, to the perfect exact width and perfectly bored at exactly 90 degrees, then hardened [ without warping ] to take the guff.
You won't likely get that degree of accuracy at home on your table top drill press ... or rubbing the gas ring evenly on a 620 grit piece of wet and dry sandpaper [ hopefully with a piece of perfectly flat glass under it to make it perfectly flat ].
With enough neversieze, the wrong castle nuts CAN be forced on, either way, and you get what you deserve with that. Having the flashider wobble is probably no big deal if you also have taper reamed it out to NM specs, right?
And when Hungry talks about things falling off ... the flashider getting wobbly is the first symptom ... then we all know what comes next??
The wrong gas lock can also be forced in, but when you consider the forces acting on that unit when the HEAVY op rod slams into the piston, which then slams into the gas plug, which then slams the entire gas assembly into the gas lock, you can see why messing with these threads is non-trivial.
Off course, you a free [ and actually encouraged ] to mess around with your M-14 in whatever way you want.
But don't blame our FAQs if your you know what falls off.
[;{)
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