I installed a new front sight on a virgin barrel and wanted to show you how I did it, and the difficulty involved. AR’s aren’t my usual thing, but I learned a trick or two for this job and wanted to pass it on. I drill the sight, ream the holes and install the pins. Use a #31 drill bit to drill the hole then ream it up to size.
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My sight was canted when I tried this. Have to put windage all the way to the left. Is there a way to fix this? Already drilled and pinned on there?
If your using a drill press and you don't have a lathe to mark the barrel, what i did, is i took a piece of paper, checked to make sure it was square with a square, then wrapped a small piece half around the barrel, insured the edge was dead center with the barrel gas hole and the 90 deg edge of the paper was against the raised portion of the barrel so it uses the milling of the barrel to make a straight line between the raised edge and the barrel gas hole so you can make a damn near perfect center mark on the barrel.
Then to insure the barrel is exactly 90 degrees I used the AR receiver flat in a vice sideways, shimmed up the gas block, ensured it was lined up with the mark triple checked it from multiple angles so ensure nothing changed after I secured it. Then drilled it with my drill press, oh and make sure you don't have a lot of bit wobble, the cheap drill press i used took a few tries and a few adjustments to make sure it wasn't wobbling around. make sure your mounting surface is level and exactly 90 degrees to your drill bit, the way i did it was super hokey. basically i used a square and made sure it was square to a longer bit on all sides. since the bit is longer, any change in angle is more obvious. If you have a better idea of checking the table Id like to hear it. because mine is difficult to do and obviously not perfect.
if you ream the first hole and put the taper pin in before you drill the second hole it would insure nothing can slip or rotate.
Thank you for making this!!! I couldn’t find anything on this either!
Is this a service you would do for me if I mailed you all the parts? How much would you charge for this?
The only video that shows how to actually drill for the pins. Thanks
Not sure if you will get this since it's been out a number of years. How much of the barrel do you try to get or does it matter. Using a stainless barrel cause any issues drilling?
What if you already installed the sling swivel and pin… any reason I couldn't use the gas tube pin hole?
You sir, are a bad ass
Thank you for posting the video.
I see the answer in the blog thank you for the great diy
is the drill bit a #30 or #31 thank you
Are you in Texas? If I send you my barrel and front sight, will you be able to do this for me? I will pay for your work, of course.
Has anyone mentioned….step#1 is to slide A-frame UPSIDE DOWN onto barrel –
look thru drilled hole and lineup with barrel gas port, gas port in block is always oversized so you may be able to side block against barrel flat and still have a gas port alignment that will work, if not, adjust and you now can see the GAP you need to work with.
Step #2……. this bottom hole can be drilled larger and tapped or at least tapped. A allen screw is used to secure block to barrel (after you correctly reinstall) use a # 31 COBALT drill, a drill press is MANDATORY….a 2/0 taper reamer to shape hole for a taper pin is used…. I cut off bayonet lug and use two dimple screws also. HOPES THIS HELPS SOMEONE.
ALL BLACK RIFLES MATTER
trim a hand guard end for the spacer
This video has helped me out big time, and I thank you for that! I hope you are well.
I have a lathe and mill, so that part is easy. I'm also using a Nitride barrel. Will the hardness of the barrel cause any problems when drilling using regular coated HSS drills or HSS straight flute hand reamers? I've never worked on Nitrided steel and I know it's quite a bit harder and I'd rather not invest in specialty carbide bits and reamers.
Also, a tip to see if your spacer (or handgaurd retaining ring) is spacing your front sight from the barrel shoulder properly: Most front sights have a hole on the bottom of the rear ring between the sling swivel legs. This hole is due to the manufacturing necessity of cross drilling the gas hole into the inside of the rear ring. So this hole is PERFECTLY inline with YOUR SIGHT'S actual gas port. If you put the front sight onto the barrel upside down with your handguard retaining ring or homemade spacer in place, the gas port in the barrel should be able to co-locate with this hole on the bottom of the front sight. If it does not, You can see how much thicker or thinner your spacer or handguard retaining needs to be to align your gas holes.
wish i had the mill machine, i did mine by had with a dremmel and a small file. it worked but took a while!
I'd love to do this; the tooling cost is just far in excess of what I'm able to afford!
Great tips, as usual. Quick question for clarification on the drill: Is the drill size #30 or #31? In the description, you posted #31 but in the video, you mention #30. I've been wondering how to get the alignment perfect and it took only a few minutes on the lathe. Brilliant.
Use same plane gas block is better. Drill holes can be bad.
Does anyone known if an F marked sight, will match a fixed carry handle AR15A2 upper?
Instead of making a custom spacer, a short length of 18 gauge bare copper wire works well – or larger diameter (16, 14, 12…) if you form into a ring and smash in vice to suit.
Knew I could count on you for a video like this 🙂
Do you think there is a way to accomplish this same job without a lathe or drill press?
Why not save yourself some time and simply grind down the old handguard retainer instead of making a whole new washer?
Very well done. I see you have great standard machining skills and lots of experience with machine tools. Liked all your shortcuts, that's how I can tell you are experienced in the shop.
Great video was very helpful. I believe you say you used a #30 drill bit? I'm measuring my taper pins and the large end is .1250 won't a number 30 be to big or did you start with oversized pins?
great video and great skills. thank you
I had a used A2 front sight post (take-off) that a friend gave me. It was drilled and roll pins were used before but me brand new Anderson barrel was not drilled. I didn't really want to notch the barrel with a dremel to accept roll pins or try to drill the barrel with the sight already drilled. I chose to tap it (#8×32) and use 4 set screws to anchor the sight post. I used a straight edge along both sides of my upper receiver channel to align the sight. Individual taps and set screws are usually available at Lowe's, Home Depot, Ace Hardware, etc. I am running a removable carry handle with the built-in rear sight and I was hitting a torso-size steel target at 600 yards the first time out at the range with just elevation adjustments on the front site only!! I am not sure exactly where it is hitting but we could definitely hear the tinking sound. We could also see the sand/dirt kick up when I missed. Next time out I will be using paper to fine tune at 600-700 yards.
@Roy Erickson, Roy I'm not able to reply directly to your comment due to your google plus settings, but to answer your question, the barrel is 3/4 inch dia. here and the probability of you getting in too close to the bore is low. Buy thats why I made the video, to show guys they may be better off getting a barrel with all the components installed.
How do you know that you are not into the barrel to much?
This video series incredible!!!! Thank yo very much for taking the time to post this series. I recently purchased a DD barrel and was wondering how to install the FSB. After watching crap videos, I came across your. Thank you again!
Do I need a spacer if I'm not going to use a standard handguard and going to a cut down fsb with freefloat?
vise grip clamp two thumbs up!!!
lathe tips very helpful
do some cuts that zoom made my eyes bug
After seeing your palmetto state armory video I got an upper from them. Very pleased. Shot today and ejection pattern was perfect. I had a dpms and switched to ak s after a bad upper dpms. Well I vowed to never own another ar but after your video I gave them another chance and was very pleased. Thank you. Bolt cutters are the best rivet tool.
Thanks for the help. Have one question I purchased a colt kit from Sarco and the front site is already drilled and the barrel is not. I would like to keep the original front sight any words of advice that you may have? I know I just can't go through the original hole the drill bit will follow the contour of the barrel intern ruining the barrel and the site. Any suggestions that you may have is more than welcome thanks again for the video have a wonderful day.
I need to have this done to my barrel can I send you mind and I'll pay you?
Informative video, Thanks for making it. Can the index marks be made without a lathe somehow? Also, although the barrel wall is quite thick, how do you determine where the pins will be drilled? Thanks again.
Just wanted to add my thanks to you for creating this video. I used your tips and methods this afternoon on a fluted YHM carbine barrel and it worked out perfectly.
Can you install one sight for me how much
Thank you!
Thats a lot more work if the barrel already has holes. I'd go the route most other guys do in that case and get a clamp on sight.
One dislike? Who would dislike this video. Thank you for posting this. I learned a lot.
Glad I could help you guys out. With so many people buying virgin barrels I wanted them to know what work was involved.
This video was a big help! Bought a stripped socom profile barrel. And used your video and it turned out perfect front sight post lined up better than the original front post! Great tips! Thanks!
Thank you for the AWESOME video. I'm new to ARs, but have a little time cranking wheels and programming M&G codes. I didn't have the confidence to tackle installing a FSB until I watched this and you made it look EASY! Thank you. The guys who have spent years throwing chips know all the tricks.
Thanks! The barrel would have been Palmetto State Armory, Bravo Company, or Daniel Defense. But I'm putting that project on the back burner for now. Great videos by the way, I've watched your kitchen build AK one several times, too bad I didn't pick up a parts kit in time.