Shaving front sight vs. lo-pro gas block

[PoliMetal]

Are there any benefits to replacing the front sight with a low profile gas block? I'm looking to put a longer ff rail on and will already need a front sight too. So is spending a little more cash on a lo-pro gas block worth it? Or am I ok with just shaving down the front sight and slapping on my rail over it. Thanks

 

[Rastoff]

I have done it both ways. There is absolutely no benefit of one over the other. However, I've found that the low profile gas blocks are so inexpensive and easy to install, it's not worth the effort to modify an A2 style sight.

In the future I will always just replace the gas block.

In this picture you can see the one draw back to the replacement option:

Just to the right of the gas block you can see a hole in the bottom of the barrel. This is where the front pin went in the A2 sight. There are gas blocks made to cover this hole, but it is only cosmetic and the blocks cost more. Since I don't care about the look, and it doesn't affect function, I got the less expensive block.

 

[PoliMetal]

Thanks Rastoff. The rail I'm looking at is 13" and going on a 16" barrel so I think it will cover the pin hole, but if it doesn't I'll be ok with it.

 

[cyphertext]

I would shave it... advantage is that you are not spending more money. If you mess it up, then go buy a new low profile block. The pinned FSB is going to be more secure than a clamp on type.

 

[shawnfergie]

Same here, shaved down in about an hour. Both pins covered and very secure.

 

[PoliMetal]

Thanks for the replies guys. Still haven't quite decided yet, if I do decide to go lo pro would I need the .750 size for the m&p sport? Mine has the 1 in 9 barrel, and I can't find anything right offhand by googling to be positive this is the right size. I don't have a set of mics handy either or I would just check myself to verify.

 

[sgtsandman]

I would replace the gas block but that is just me. I look at it as having spare parts for a future build or if I choose to go back for some reason. Options are always good.

 

[Rastoff]

...if I do decide to go lo pro would I need the .750 size for the m&p sport?

Exactly correct.

 

[BIGmuddyBRONCO]

Yep .750 is the size you need. IMO if you are covering the block with a free float guard then I would just shave it since it won't really be visible anyways. If your block will be visible then I would replace it.

 

[PoliMetal]

thanks for all the help, think i will be going with a BCM gas block to go under my new 13" KMR.

 

[BIGmuddyBRONCO]

I love BCM stuff however I have some kind of weird infatuation with Yankee Hill machinery products so I usually end up with their stuff instead... lol

 

[JaPes]

I love BCM stuff however I have some kind of weird infatuation with Yankee Hill machinery products so I usually end up with their stuff instead... lol

YHM gas blocks are good to go.

 

[dullh]

I would just replace the front sight with a YHM lo-pro gas block.

I shaved my A2 front sight off and then wish I hadn't...I ended up going with this gas block:

Yankee Hill Machine Low Profile Gas Block Assembly - YHM-9381A - Primary Arms

I wanted to reuse my A2 FSB on a different rifle after all but...I shaved it so I couldn't!. The gas block shown above covers up both the pin channels in the barrel so you don't see them anymore.

 

[dullh]

thanks for all the help, think i will be going with a BCM gas block to go under my new 13" KMR.

My KMR is a 10" on an 11.5" barrel:

 

[Argonnakid]

Shaving the site down might be a better choice. I had a bear of time getting my taper pins out. Heat, cold, and finally a 5lb. hammer.

 

[PoliMetal]

Just a quick update, got it all put together and the EOTech xps2 thrown on there. Ill work on getting some pics up in the next day or so.

 

[kujiin]

Removing the front sight post and replacing it with a YH gas block with the front sight built. Will the front still be in line with the rear flip up sight? M&P 15 sport.

 

[MrG5122]

Should line up fine.

 

[sgtsandman]

As long as the block is lined up with the gas port on the barrel properly, the sights should line up fine.

 

[AreWeNotMen?]

FWIW I had the same conundrum, and because I was bored and impatient I shaved the existing gas block sight rather than buy something. It took a bit of time to do the final shaping, paint, etc, but it was really fun to do (my first).