Has anyone ever sawed  their Factory front sight down to a lower level,In order to keep the best gas seal,while getting rid of the obstructive view.

And then used say a KAC Front Flip Up sight on their RAS?Im thinking of trying it.

Can this be done?

If so any tips? Or Pics?

Thanks for any info in advance.

Jm03

I've taken a hacksaw to the bayonet lug. And will be taking off the top of a sight tower soon-with a hacksaw. I'm going to use a rifle FF RAS on a 16". Since the hacked sight base will be under it, who cares. If you want to squirt it with some paint or refinish it, that can be done to.
It will function just the same, no need to spend money on a gas block that does the same and can't be seen.

Mark

I chopped mine off so I could put a full length handguard on my 16 in upper. I used a dremel, a hacksaw,a file, and some gun blue paste ( I felt like a pakistani gunsmith [:D]).

It works just fine. If I get a chance (when I get home) I'll take actual pics of the block after I chopped it.

[img]http://www.hunt101.com/img/047933.jpg[/img]

Thanks,
Thats pretty much what I was thinking.I will post some pics when I get it done in the near future.

Jm03

I just did it last weekend. i used a grinder with a cutting disc to take off the bayo lug and sight tower. cut like butter. i used the dremel to clean it up and make it look acceptable. it would take less than 15 mins with the right tools. you make it look as good as you want. the more time you spend, the better it will look.

High tech operator huh. [hail] [:D]

Hacksaw, grinding wheel and a black Sharpie did it for me.

I've never done it before but had thought about it. The only reason I didn't is because once you
saw/grind off the front tower, you're pretty much stuck with that configuration. The tower is mated and machined to the barell so it aligns correctly with the gas port. It's one part that you just can't buy online or at a gun show and expect it to fit correctly. If for some reason you wanted to go back with the old set-up, youl'd have to get a unit that attaches with set-screws, or get an undrilled blank and have a gunsmith fit it. Rather than do all that, I bought a low profile gas block that attaches with set-screws.

[hail2][size=3] We are not worthly[/size=3][hail2]

Seriously though, that looks very nice.

I figured if I screwed it up real bad I would have an excuse to get a PRI flip up or something [:)]

I cut mine off in order to put on a BM folding front.
[img]http://photos.ar15.com/ImageGallery/Attachments/DownloadAttach.asp?iImageUnq=14710[/img]
To be honest, it was the dumbest bit of "gunsmithing" I've ever done (I THOUGHT I'd like the Eotech better without the front sight in the view), so I got rid of it. From now on, any optical sight I get is just gonna have to either see over or around the standard front sight.

that's the beauty of home gunsmithing. it's NOT high tech at all. i don't need CAD computer and a CNC machine in my spare bedroom. i figure the ar15 was designed for gunsmiths with a 6th grade education and the 1911 was designed for smiths with an 8th grade education. which is good for me since i never made it past 9th grade.

all jokes aside. the simplicity of the AR is what draws many to it. it's easy to understand and isn't intimidating. i built 2 of the 3 i own. i bought my 1st one in feb of this year. it drew me in quickly.

I have done it two different ways,
1. Do not remove upper receiver assy. and front sight/gas block assy from barrel.
In this case I wanted to leave enough material "on top" to later file a pair of tapered dovetails so a new front sight would slide on like a pair of Sako Scope Rings.  So I wanted the top surface to be flat and plumb with the flat top upper receiver rail (even though they would be at different heights).  So after hacksawing off the front sight "A-frame" well above the gas tube support section, I turned the upper receiver over (sights down).  My work bench was smooth masonite and I had duct taped a large mill file to one end with the cutting edge of the teeth pointed towards the center of the bench with a piece of scrap hardwood under it so the cutting edge of the file was plumb with the centerline of the bore.  I then covered the upper receiver rail with smooth tape and applied some grease to it.  So now I could move the whole UR back and forth by lightly holding down the read of the UR, while pressing down on the bayonet lug.  This allowed me to "file" the hacksawed surface of the front sight A-frame perfectly flat, and this came out looking really nice.  Needless to say, this procedure is for those of us without a vertical milling machine.
2. After removing original front sight / gas block.
This is the method I recommend if you realy want the minimum bulk (like for under a FF RAS).  I grab the top of the front sight a-frame that I'm going to throw away in the vice and carefully hacksaw off the part I want to keep.  Use a bench grinder to remove most of the excess "meat".  Then I use a vertical belt sander with the sander's adjustable table set at 90 degrees to the belt.  This allows you to use the flat rear surface of the sight to keep the surface you are smoothing down perfectly perpendicular.  You can also easily rotate the piece from like 9 to 3 o'clock while using the belt sander in this manner and achieve a nice minimum bulk, rounded over look.  I have also done this with just a file, but a good belt sander is the way to go.  Even if you don't have a belt sander now, just doing one front sight "correctly" will convince you that buying a nice Craftsman bench mounted vertical belt sanded was worth the investment.
While you are doing this, keep a bucket of water within reach and keep dipping the part as it heats up.  Also make sure the sander's adjustable table is close to the belt so the part can not get "sucked in."
This method also gives you the oppotunity to remove the forward handguard cap as well, which is usually the case when free-floating the barrel inside a forend tube.  

"I have done it two different ways,"

What don't KAC employees get a discount on low profile gas blocks?

The low profile block is easy to install (I just put a drill bit into the bottom hole on my forged post and drilled a 1/8in recess for the rear screw and then assembled and tightened the srews (the rear screw alligns the block with the gas tube hole, as both holes are at the same location as the gas port hole.))


[b]I have cut off 3 posts when I made an order to BM for V-match uppers and got them without V-match blocks. IT WAS A PAIN IN THE ASS. They take about 1/2 hour each with a dremel tool and cutting disks, I ground them flat, and then re-blued with cold blueing. (if you hit the metal right as you finish it is a very dark blue) - any time that lapses makes the blueing less effective- problem with dremels is those damn fine metal shavings that always stick in your hands I was pulling them out for days.[/b]

GreenO, I refer back to the topic's initial question:



So I focused my answer to his question.  Even though I like our (KAC) low profile gas block and I do get an employee discount, I don't believe that any "after-market" gas block assy can match the gas seal and "marraige" that can be established in the proper factory set-up when the tappered pins are drilled and the pins then set--before the parts are removed from the fixturing.

Now *that* I like [the sight]...I have a 20" HBAR that I want to move the sight to the end of the barrel, and install carbine handguards...I'm gonna haveta hump over to BM...

My poor credit card...I abuse it so...(lol)...

Edit: Here's a funny...On their BM 16" Modular Carbine, BM mounts the front sight backwards, so it flips forward to clear the handguards...

[url]http://www.bushmaster.com/shopping/uppers/post-ban/pcwvmb16fmc.asp[/url]