To drill a hole or not?

[ntsqd]

Stage or step drilling used to be what was taught, it was what I was taught in HS. What I've since learned and was taught in successive Technology classes is that every step is another opportunity for the hole to move from where you want it to be and is time consuming. Now the process taught is:
1) Center/spot drill where the hole should be.
2) Pilot drill with a drill slightly larger than the web of the finish drill so that the finish drill doesn't have to work as hard.
3) Drill to size.

None of which matters because the hole needs to intersect the surface at an angle if it is to be coaxial to the CL of the screw in question. The only solid way to do that is to plunge it with an endmill.
OR drill a hole perpendicular to the surface and make it big enough for the hex key to go thru it at an angle.

I should put all of the "educational" parts that I've bought on Gun Broker......

 

[B23]

If you calm down, grab a beer or two.. or like me grab a Bacardi and juice. then take the handguard off the rifle if you know how.

I like the way you think, only problem, I rarely drink, so if I have a few beers and or a couple two or three cocktails, my vision/judgement will likely be so blurred I'll end up drilling a hole on the wrong side. J/K of course.

I did the barrel swap myself so I've had the handguard off and this gun apart more than just about any I own. I'm really not even that big of an AR guy but I've had this thing apart and babied it more than any gun I own. I bought this gun new from Cabelas as a SP10 308 a few weeks ago and never fired a single shot through it. I've swapped the stock from the original Magpul STR to a PRS Gen3, swapped the barrel to a Proof Research CF 6.5 Creedmoor, changed the gas tube and put a new .875 journal adj GB, and still haven't put a single round through this thing yet. I'm starting to think I have OCD or something. Hmm, maybe I should dust off the bottle of Jamesons and pour myself some.

 

[freddiej]

I like the way you think, only problem, I rarely drink, so if I have a few beers and or a couple two or three cocktails, my vision/judgement will likely be so blurred I'll end up drilling a hole on the wrong side. J/K of course.

I did the barrel swap myself so I've had the handguard off and this gun apart more than just about any I own. I'm really not even that big of an AR guy but I've had this thing apart and babied it more than any gun I own. I bought this gun new from Cabelas as a SP10 308 a few weeks ago and never fired a single shot through it. I've swapped the stock from the original Magpul STR to a PRS Gen3, swapped the barrel to a Proof Research CF 6.5 Creedmoor, changed the gas tube and put a new .875 journal adj GB, and still haven't put a single round through this thing yet. I'm starting to think I have OCD or something. Hmm, maybe I should dust off the bottle of Jamesons and pour myself some.

sounds like you are not OCD. it sounds like you are just picky on how you want your AR-10 to feel in your hands. I would say if you are handy with tools then this hole should be little to no worries for you to complete. it's a simple thing to do. try replacing a barrel bead on a shotgun without boring through the barrel into the choke. that is a bit nerve raking. BTW that is what I have to look forward to after sending this one off. the shop has been a blur of people and phone calls today. I have been typing and helping people on the phone this morning.. some of the same BS I hear every day so I got a few minutes to type people and have some fun with the people here.. sounds like you are trying for a designated marksman's rifle. good on you for that. like I stated before.. the hole should be an easy thing to do. if it was my rifle I would have used a small end mill and put a slot in the end of the handguard so I could adjust the gas block. but that is just me. later tatter.

 

[wwbrown]

How about a cutting torch

 

[eklarsen]

You are just making it a custom gun, drill it.

 

[ntsqd]

Another thought is that there are guys with portable plunge EDM machines. They're usually employed removing broken bolts in heavy machinery, but might be willing to tackle such a small screw.

 

[Laelkhunter]

I say drill it. I would. If you decide to drill it without removing the handguard first put something between the handguard and the gas block/barrel like a piece of wood or plastic just so you don't punch through and scar up anything underneath the handguard. As others have suggested, drill a pilot hole first.

 

[B23]

So tell what you guys think of this idea.

Since the handguard is at an angle the hole will also be at an angle, but the GB adjusting screw is not angled. If you look at the picture it'll probably make sense. What do you think about grinding a little scallop shape in the handguard similar to how I have the red line. You can't really tell by the pic but the GB adj. screw is only covered by about an 1/8th inch of the handguard.

I'm sure I am wayyyyyyy over thinking this, but, unfortunately, this is what I do when I'm not exactly sure how it'll look and the last thing I want to do is make it look ghetto.

Thoughts???

 

[ntsqd]

Best way to do that, that I can think of, is to clamp it in a mill vise on the top of the rail and the bottom surface and then 'bump' it with the side of an appropriately sized end-mill. Can create the same effect with a carbide burr in a Dremel or die-grinder, but it will be a whole lot harder to make as uniform of a notch. If you're anywhere near the Lower Left Coast I'll offer to do it with a mill should you not have access to one.