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Posted: 4/30/2006 9:27:26 AM EDT
| i have a 16" colt barrel with an "F" marked FSB. I plan on using the barrel on an A2 build i've been thinking about. i found the A2 FSB for sale at bravocompany, but it says it needs to be drilled. do they sell pre drilled A2 FSB? what does drilling the FSB for taper pins entail? |
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Just use the "F" FSB for your build... Worst case scenario is that you will need to screw the FSP down a bit... And to answer your question... You can NOT buy a pre drilled FSB to match your existing drilled barrel... When a FSB is installed onto a barrel it is married to it and will not be interchangeable with others... If you would want to add a new FSB you would need to drill the new one to match the barrel... ETA: In order to correctly install a M16/AR15 FSB assembly you will need the following tools: End mill (digital read out is nice), fixture and drill bits... First thing to do is to make a fixture which can hold your new gas block in place and fix the depth of the new holes... You can make the fixture out of an aluminum rod (which fits the inside diameter of the gas block, acting like the barrel), and mill one side of the rod flat... The flat edge corresponds to exactly the depth of the top or leading edge of the holes in the old gas block... Install and attach the old gas block onto the newly made fixture using the set screw hole (where the sling attaches)... Now, place the fixture and old gas block in an end mill and determine the distances between the two holes (a digital end mill makes short work of this step)... Remove the fixture and old gas block, install the new gas block and place this unit back into the end mill vice making sure that the fixture is absolutely parallel with the end mill surface... Drill the two holes at the specified locations as found from above... The end result is a new gas block that will have exactly the same hole location as the old gas block... |
| In most cases you can easily adjust the FSP up or down to compensate for the specific type of upper receiver that's being used with an "F" stamped FSB... If by chance it doesn't turn down far enough, just file a few thousands off of the post to achieve the proper elevation adjustment... If its the other way around and the FSP is being raised to the point of running out of thread, then replace the FSP with one that is .040" taller... |
I keep reading about the .040 taller FSP but don't seem to be able to find them. Could someone tell me who sells them? Thanks in advance Elvis |
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