[Scorpio]

So, my original plan was to use an A2 shark fin with a flip up rear sight on an M4gery flat top build, but my plans have gone awry. My original plans to use a 14.5"bbl with a linear comp changed to a 16" bbl with a thread protector. I could not find a 14.5" bbl with the features I wanted so I decided to go with a 16" that had everything I was looking for, except one thing.

I did not realize that the barrel needs to have two small dimples under the gas port for the A2 sight pins and the barrel I bought does not have them, so no A2 for me unless I want to use a clamp on, which I don't, or pay a smith to drill them in, which will cost too much in NJ dollars.

Now I'm looking at either a two piece Yankee Hill gas block with a flip up sight or a two piece picatinny gas block with an add on flip up sight. The reason for two piece is that I live in Newjerseystan and my muzzle device has to be pined and blind welded. Going with a two piece will make future changes easier.

The number of combinations of gas blocks and sights is a bit overwhelming. I think I have it figured out but I really can't be certain. If I go with the YHM gas block with the built in flip up sight, it would make selecting a rear sight a little easier I think, but it has been suggested that going with a picatinny gas block would be better. They seem to come in a variety of heights so I'm concerned that I'll mismatch the height for the front and rear sights.

I'm leaning towards Magpul Mbus, maybe the Mbus pro. The pro version appears to be taller than the regular old Mbus. If I get a rail height picatinny gas block it seems like some sights will be too high, or if I get the regular picatinny gas block the front sight may be too low. I do like the YHM with the built in flip up but if the sight goes wonky then I have to replace the whole thing.

Is there any easy way to figure out how to match gas blocks with front and rear sights?

 

[Neon Horse]

It can be a pain. It'd be easier to pick a block and then a sight. If you like the YHM flip up, get it. Worrying about the what-ifs ruins the fun. I have an AR with a gas block that is not rail heught. YHM makes sights for that.

Why not just throw a free float rail and a low profile block? Then you can use Magpul, Troy, or whatever you want without worry.

If you do get a railed block, be careful with polymer sights... there is potential for melting.

 

[Scorpio]

Okay, I have it figured out. Not! What the heck is the deal with railed gas blocks. Hardly any of them are on the same plane as the receiver. I do not like buying Chinese stuff but the only railed two piece block I've seen is MIC. <puke>

So, is there something I'm missing here, are the short blocks designed to line up with sights matched to the height, or will I have to buy a riser for the block, in addition to the front sight. Man, this is just getting stupid.