Hi guys,

It is my first time posting on this forum and I look forward to using this valuable resource. I'm from New Zealand and experienced gunsmiths with AR-15's or people knowledgeable with the platform are difficult to find.
I purchased my first Windham Weaponry SRC 16" (M4). It has a picatinny gas block.

http://www.windhamweaponry.com/pdf/NewTechSeets/SRC%2012-17-12%20MSRP.pdf

I am a service rifle shooter so the rifle has to be as close to as issued condition as possible. Hence, I purchased an A2 front sight and removed the picatinny gas block. However, the A2 front sight doesn't line up with the holes (detents?) in the barrel. I have purchased a detachable carry handle with a 6/8 marking on it so I hope this is compatible as well.

The A2 sight I purchased has a square front post and 4 detents for adjustment.

Woud anyone be able to shed any light as to what component I need, and maybe why this doesn't fit? I may have to order from the USA as parts here in NZ are hard to come by. I am regretting removing the original gas block!

Thanks so much guys,

Dominic

Front sights are pinned to the barrel and end up very strong.  If yours is connected by set screws they will not likely  line up with the old set screws, they are not a standard connection method with a universal fit.   Drill new holes if needed.

Can you find someone to mill some flats on the barrel for the screws to dog on?

That's normally how that's set up on a Service Rifle barrel.