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8/26/2010 3:06:28 PM EDT
im going to tap a front sight base to be used on a service rifle.  is there a standard thread pitch that is used ie; fulton armory, creedmore.... i will also need to dimple my barrel to match.  is there a spec for that that the major manufacturers cut their barrels to?
8/26/2010 3:53:53 PM EDT
[#1]
#8x36 TPI is about standard.  This matches the front sight post so you can use the same setscrews for under the sight post, locking this adjustment.



You need an end mill to spot the flats in the barrel.  If you are retrofitting an already taper pinned barrel, you should fill the taper pin holes in the barrel with brass rod, suitably tapered and fit into the slots.  Then center a 0.150 end mill over each filled hole and mill the flats.
8/26/2010 4:59:15 PM EDT
[#2]
ive used an 8-36 on my 9mm upper.  it had a very wobly front sight.  the barrel has never had any taper pins.  it had a railed gas blick with teh one setscrew underneath.  its a WOA 1-8 douglas.
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