Upper build questions

[Stan_TheGunNut]

Hello all. I'm about to begin working on my first build since I have accumulated an assortment of parts, and have a couple of questions about installing the front sight base. I bought a standard front sight base without realizing it didn't have the holes already drilled in it to drive the taper pins in. I guess I wrongly assumed there was a standard dimension. Without having to go to just a gas block (I prefer the look of the standard front sight base) whats' the best way to ensure that the holes in the front sight base are drilled correctly and how do I ensure that the front site base is mounted TDC and not canted?

My initial thoughts were to make sure that I had the barrel mounted to the upper receiver (a flattop) and attach a rear sight to it, and then just kinda sight down the length of the barrel, but I'm not sure if this would be precise enough.

The barrel I bought used with a few hundred rounds thru it, and it already has holes in it for the taper pins.

Thanks for the help.

[Soulrack223]

I believe there is a specialized jig they use to do this, but it may not be possible now that the barrel has it's holes drilled and its matching FSB is missing. FSB installation is something best left to a professional. Steve at Adcofirearms.com can probably do it for you. If you look under "Shop Services" it says:

"FSB Install: No-Ban FSB on your .750 barrel $85.00
We supply and install a bayonet lugged FSB onto your barrel. Same price to drill/pin a customer supplied FSB."

The rest of the upper assembly is pretty easy provided you have the correct tools.

[Stan_TheGunNut]

Thanks for the link and information Soulrack. I'll contact Steve at AdcoFirearms.

[warpigM-4]

+ 1 for steve he will take good care of you:D