low profile gas block

[wylie won]

I want to replace the A2 front sight on my Sport with a low profile gas block.

I was thinking this would do nicely

Yankee Hill Machine Gas Block Single Picatinny Rail AR-15 LR-308

Is the inside diameter correct?

[MistWolf]

If the Sport barrel is .750 inch at the gas port, yes. Do you really need the rail? That style gas block is heavier than the regular lo-pro gas blocks.

You should consider cutting down the front sight block instead

[wylie won]

Cutting it down sounds tempting.

[wylie won]

Has anyone here shaved down their front sight? What were the results?

[Kadonny]

I went low profile but I wanted a free float to fit over it and didn't care for the railed block. As for the A2 post, just remove it and replace it with a low profile and keep th A2 as OE. The hardest part is to get those stock pins out of the A2 sight.

[MistWolf]

Why bother to remove the front sight base, pay for a replacement gas block and install it when a trim job will be a simple and more durable solution?

[wylie won]

Mistwolf, I agree it would be cost effective, but I worry about the aesthetics of the "trim job." So, you didn't remove the front sight when you trimmed it? Do you have pics on how it turned out?

[MistWolf]

I have not trimmed mine, but when I do, I won't remove the FSB from the barrel. I want the pins firmly in place.

Before anyone says anything about my not having actually trimmed one yet, I've been cutting metal professionally as an aviation technician for decades and this little trim job is simple and straight forward.

You can do a search on the internet and find photos of trim jobs. If you're worried about looks, either do a neat job or plan on getting a free float handguard long enough to cover the gas block

[cyphertext]

Originally Posted by MistWolf

If you're worried about looks, either do a neat job or plan on getting a free float handguard long enough to cover the gas block

The only reason I would remove the A2 FSB would be to put on an extended free float rail, and at that point, the rail would cover the chop job. Shave it and hit it with hi temp paint... done.

Not my pic, but...

[Kadonny]

Originally Posted by cyphertext

The only reason I would remove the A2 FSB would be to put on an extended free float rail, and at that point, the rail would cover the chop job. Shave it and hit it with hi temp paint... done.

Not my pic, but...

If you plan to install a free float rail with any type of proprietary barrel nut, the FSB has to come off anyway, that's why I chose just to put a low profile on and I still have my stock FSB in tact.

[cyphertext]

Originally Posted by Kadonny

If you plan to install a free float rail with any type of proprietary barrel nut, the FSB has to come off anyway, that's why I chose just to put a low profile on and I still have my stock FSB in tact.

Shave it and pin it back on... If you remove it, you are not very likely to use it later down the road for anything and if you decide you want the A2 back, cheap enough to buy a new one at that point.

Not a big deal either way, but I wouldn't spend any more money than I had too...

[ChattanoogaPhil]

Cutting off the front sight is so rookie....
You don't want to look like a newbie at the range, do you?

Get a torch and heat up the front sight. Then bend it over 45 degrees. It will be out of sight picture. If you ever want to go with offset sights all you'll need is the rear sight. Of course if you later change your mind you can always bend it back. Thinking ahead is the key to tacticalness.

[cyphertext]

Originally Posted by ChattanoogaPhil

Cutting off the front sight is so rookie....
You don't want to look like a newbie at the range, do you?

Get a torch and heat up the front sight. Then bend it over 45 degrees. It will be out of sight picture. If you ever want to go with offset sights all you'll need is the rear sight. Of course if you later change your mind you can always bend it back. Thinking ahead is the key to tacticalness.

No fair recycling your humorous posts on this subject!

[MichiganScott]

Am I the only one that likes the look of an A2 front sight tower when using regular non-railed handguards? I mean low profile with a free floating guard is one thing, but..........

[wylie won]

Ok... I took off the A2 frontsight. Two of the pins were no problem. That last pin was a nightmare. Now, I'm just waiting for UPS to deliver my new gas block

[Kadonny]

Originally Posted by wylie won

Ok... I took off the A2 frontsight. Two of the pins were no problem. That last pin was a nightmare. Now, I'm just waiting for UPS to deliver my new gas block

Umm, there are only 2 pins that pin the sight to the barrel, unless you count the roll pin for the gas tube which is easy to get out.

[wylie won]

Yes, I'm counting the roll pin also. That one was easy.

[Crubs]

This is my sport with shaved A2 FSB.

[RDFabsRep]

For what it's worth...

I recently changed out a factory 2-piece handguard (carbine) to the Troy Battle Rail, which uses the factory barrel nut. Initially I was going to remove the FSB and install a low profile gas block. But then I got to thinking: I'd have to dimple the barrel, pay $XX.XX for the block, probably snag a new gas tube... Then I'd have to buy a good thread locker, test it for function, make sure the set screws didn't back out... On the flip side, the FSB was already pinned to the barrel and had proven reliable over the course of hundreds of rounds. Plus, it'd be completely covered by the rail. I'm no stranger to a side grinder, so the choice seemed simple:











I could've smoothed the block out more, to make the lines perfect--it was actually hard not to. But it's under a rail and you can't see it; I figured it was good enough. Flat black grill paint was a damn close match to everything. Hope this helps.

[wylie won]

Very nice RDFabsRep! I decided to take off the A2 Front Sight and replace it. I also replaced my 1-4X24 with a Vortex Spitfire. I'm pretty happy with the results. I took it to the range last weekend and shot a couple of hundred rounds through her. She performed like a champ.

Here's a before and after pic...

[Kadonny]

Originally Posted by RDFabsRep

For what it's worth...

I recently changed out a factory 2-piece handguard (carbine) to the Troy Battle Rail, which uses the factory barrel nut. Initially I was going to remove the FSB and install a low profile gas block. But then I got to thinking: I'd have to dimple the barrel, pay $XX.XX for the block, probably snag a new gas tube... Then I'd have to buy a good thread locker, test it for function, make sure the set screws didn't back out... On the flip side, the FSB was already pinned to the barrel and had proven reliable over the course of hundreds of rounds. Plus, it'd be completely covered by the rail. I'm no stranger to a side grinder, so the choice seemed simple:



I could've smoothed the block out more, to make the lines perfect--it was actually hard not to. But it's under a rail and you can't see it; I figured it was good enough. Flat black grill paint was a damn close match to everything. Hope this helps.

Good enough? It looks great and you did an awesome job.

I chose a rail that had a proprietary barrel nut, so the post had to come off my rifle anyway, but a shaved post is a great way to do it if you use the factory nut.

[RDFabsRep]

Originally Posted by Kadonny

Good enough? It looks great and you did an awesome job.

I chose a rail that had a proprietary barrel nut, so the post had to come off my rifle anyway, but a shaved post is a great way to do it if you use the factory nut.

Thanks for the compliment, man. And sorry...I worked in a custom fab shop for 7 years. My attention to detail had to be top-notch. That gas block to me is "super rough." When I would normally grind/scotch brite a part, welds would disappear and there would be no harsh lines.

[Rastoff]

Originally Posted by RDFabsRep

Thanks for the compliment, man. And sorry...I worked in a custom fab shop for 7 years.

For someone who worked in a custom fab shop, yes, it is rough. However, for the rest of us, it's fantastic.

I did the same thing with one of mine, but I stopped at pic 3. I was all about function and cared not for how it looked. Dude, you can modify my A2 into a gas block anytime.

[mini14jac]

Originally Posted by RDFabsRep

For what it's worth...

I recently changed out a factory 2-piece handguard (carbine) to the Troy Battle Rail, which uses the factory barrel nut. Initially I was going to remove the FSB and install a low profile gas block. But then I got to thinking: I'd have to dimple the barrel, pay $XX.XX for the block, probably snag a new gas tube... Then I'd have to buy a good thread locker, test it for function, make sure the set screws didn't back out... On the flip side, the FSB was already pinned to the barrel and had proven reliable over the course of hundreds of rounds. Plus, it'd be completely covered by the rail. I'm no stranger to a side grinder, so the choice seemed simple:











I could've smoothed the block out more, to make the lines perfect--it was actually hard not to. But it's under a rail and you can't see it; I figured it was good enough. Flat black grill paint was a damn close match to everything. Hope this helps.

Top notch!
So what rail is that, and did you have to remove the FSB to install it, or were you able to leave it in place?

[RDFabsRep]

Sorry...just noticed your post. The rail is a Troy VTAC Alpha--top notch in terms of fit and finish.

No--the FSB never technically came off. From picture 2, I hacked off the top of it, making it look like picture 3. Then I re-shaped it, which gives you picture 4. At that point, the rail fits right over both it and the existing FH/muzzle brake.

[therapture]

I also cut my A2 off. I shaped it (roughly) and put some perma blue on the bare metal. Looks decent and man, I really like the open FOV with my EXPS2.

I also installed magpul folding backups, as I fully intend to keep decent aiming skills with both sights.