31 October 2012, 15:40
z375Machining a Banded Front sight
I've been giving thought to making a banded front sight for one of my barrels, the muzzle OD will be 1.000", this is a 12ga bore rifle project, the barrel will have a heavy taper, for the front sight I thought something along the lines of an NECG sight will look nice coupled with a NECG masterpiece rear sight, trouble being that they dont make a banded front sight with a ID in this size, any suggestions on how to go about this from scratch? Anybody here every build one in a custom size?
31 October 2012, 17:49
BobsterI think the book Modern Gunsmithing by Howe may have that information. I'll check today.
quote:
Originally posted by z375:
I've been giving thought to making a banded front sight for one of my barrels, the muzzle OD will be 1.000", this is a 12ga bore rifle project, the barrel will have a heavy taper, for the front sight I thought something along the lines of an NECG sight will look nice coupled with a NECG masterpiece rear sight, trouble being that they dont make a banded front sight with a ID in this size, any suggestions on how to go about this from scratch? Anybody here every build one in a custom size?
31 October 2012, 20:16
J.D.SteeleNot a problem if you have a mill, more if you don't but it's doable anyway. I've made several banded front swivel bases from solid stock with nothing more than files and a grinder so a sight ramp wouldn't be much more difficult.
Bore the big hole first and use it to hold the unformed block for shaping the ramp. I simply jammed the unformed bored block onto an appropriately-sized round stock and then cut the sides with my grinder and coarse files, finishing the thinner portion on the bench grinder. In your case you would also cut away all the unwanted band material from the 'tail' of the ramp.
My cross-hole for the swivel was easy to drill while, for your NECG front sight insert, you will need the special little dovetail milling cutter sold for this purpose by NECG. If you don't want to buy the cutter then it's easy to make a 2-fluted one from a small piece of drill rod or a broken drill bit.
The smaller cuts for the various screws, hood, pins, spring-&-plunger, etc can be made while the ramp is being held on the round stock and you can also stipple or checker it as well, before final assembly onto your barrel.
IIWY I'd begin with a chunk of steel ~ 1.25"x2"x4".
Also IIWY I'd follow the standard machining practice of beginning with 2 or 3 chunks in order to have spares. Reasons? Sometimes an error will require scrapping a piece and so you'll have spares to take up the slack. And if you DO finish the spares then you'll have the extra ramps for future projects or to sell/trade to your colleagues here on AR!
Good luck and regards, Joe
31 October 2012, 20:55
montea6bA few years ago someone posted an excellent pictorial of the entire process. Perhaps a search would turn this up...
Meanwhile, here is another one I found:
Machining a front sight band02 November 2012, 12:17
z375quote:
Originally posted by J.D.Steele:
Not a problem if you have a mill, more if you don't but it's doable anyway. I've made several banded front swivel bases from solid stock with nothing more than files and a grinder so a sight ramp wouldn't be much more difficult.
Bore the big hole first and use it to hold the unformed block for shaping the ramp. I simply jammed the unformed bored block onto an appropriately-sized round stock and then cut the sides with my grinder and coarse files, finishing the thinner portion on the bench grinder. In your case you would also cut away all the unwanted band material from the 'tail' of the ramp.
My cross-hole for the swivel was easy to drill while, for your NECG front sight insert, you will need the special little dovetail milling cutter sold for this purpose by NECG. If you don't want to buy the cutter then it's easy to make a 2-fluted one from a small piece of drill rod or a broken drill bit.
The smaller cuts for the various screws, hood, pins, spring-&-plunger, etc can be made while the ramp is being held on the round stock and you can also stipple or checker it as well, before final assembly onto your barrel.
IIWY I'd begin with a chunk of steel ~ 1.25"x2"x4".
Also IIWY I'd follow the standard machining practice of beginning with 2 or 3 chunks in order to have spares. Reasons? Sometimes an error will require scrapping a piece and so you'll have spares to take up the slack. And if you DO finish the spares then you'll have the extra ramps for future projects or to sell/trade to your colleagues here on AR!
Good luck and regards, Joe
Thanks for the heads up on this, Joe! I initially was contemplating getting the damn thing wire-cut, but promptly dropped the idea after the quote I got from the machinist!!
But your method seems the easiest way yet to do this! Just for the record, NECG makes a banded ramp with a .945" I.D, they haven't mentioned the wall thickness of the band, but do you think it will be worthwhile to ream out the extra 0.055" to get it to fit the barrel? I'm guessing there wont be much strength left in the band once this is done