Is the 516 barrel proprietary? Can I use regular AR barrels? I need a 16 inch not the 14 with a pinned flashider. Any gunsmiths in the Marietta area that can pin my silencerco qd mount for cheaper than buying a new barrel?
Help please
Philip

Its a piston gun. so everything in the barrel area is proprietary.

I presume Marietta, Ga. Try Deercreek Gun Shop on Fairground St.

barrel is a standard AR barrel, it's the barrel nut & piston system that is proprietary.

I've not really followed this, but how you can use a std. AR barrel? How does one attach the SIG piston system and gas block?

quote:

Originally posted by hrcjon:
I've not really followed this, but how you can use a std. AR barrel? How does one attach the SIG piston system and gas block?

the system (block) is pressed on and pinned to the barrel

It might be semantics, but I would not consider it a "standard ar barrel" if you have to (find)/use a proprietary SIG gas block and then machine the barrel to pin it.

It's a standard AR15 barrel, it is not proprietary. You don't have to machine the barrel. The gas block is not the barrel, it's a gas block, and can be re-used when replacing the barrel.

OK again semantics. BUT if you have to pin a gas block you have to machine the barrel, in some form. but whatever.

This message has been edited. Last edited by: hrcjon,

quote:

Originally posted by hrcjon:
OK again semantics. BUT if you have to pin a gas block you have to machine the barrel, in some form. but whatever.

I agree with the above.

Just because you have to drill for the gas block doesn't make the barrel proprietary. If your AR-15 uses a fixed front sight base and you change the barrel and you want to use the front sight base on the new barrel you still need to drill, taper ream, and install the taper pins to attach it to your new barrel. No semantics there, it is still a standard AR-15 barrel, just how the gas block/front sight base is attached.

I guess in some sense it all comes down to do you consider the gas block part of the barrel? The official military answer is yes. You may not feel that way. But having to pin a proprietary gas block to a barrel to make something work in my mind makes the whole thing "proprietary". But in any case at this point we have told the OP that he has to solve the issue by getting an AR barrel and the unique Sig gas block and getting it pinned to the barrel. QED.

quote:

Originally posted by hrcjon:
I guess in some sense it all comes down to do you consider the gas block part of the barrel? The official military answer is yes. You may not feel that way. But having to pin a proprietary gas block to a barrel to make something work in my mind makes the whole thing "proprietary".

Now you are just making stuff up.

The 516 gas-piston system, including the gas block, is of course proprietary. Everybody knows that. But the barrel is not the gas block. They are distinctly different parts. Just like a barrel nut is not a barrel, and a gas tube is not a barrel. The Sig 516 uses a standard non-proprietary AR15 barrel. Period.

Here is an early M16 MIL-SPEC drawing for a barrel. There is no gas block in this drawing because this is a barrel drawing and the gas block is a different part. Your assertion about "the official military answer" is wrong.



You are confused about the difference between a part and an assembly. A barrel assembly may include a proprietary gas block, but that does not mean that the barrel part itself is proprietary, which is exactly what the OP was asking about.

By your definition this Daniel Defense barrel is proprietary because it uses a proprietary low profile pinned gas block that is not the original A2 FSB. Obviously that’s a silly argument to try and make because DD is using a standard M4 spec barrel.

https://www.primaryarms.com/da...-nato-carbine-length

Look, I’ve read enough of your posts to know that you have a strong hatred for Sig, and I agree with several of the points that you have made regarding their past mistakes. But maybe in this case it’s ok to admit that Sig may have done something right by using a standard barrel which can in fact be replaced with another standard AR15 barrel if you manage to shoot one out. All you have to do is retain the original gas block that was removed from the old barrel, and then reinstall it on the new barrel. Just like any other DI rifle that is using a proprietary low-profile gas block.

At this point I think the OP has the answer to his question. I can agree with you that you can start with a standard AR barrel and make a usable barrel assembly for a 516 by adding the SIG proprietary gas block. But that misses my point totally.
1. I have no idea if the OP considers the project of moving the SIG gas block over to another barrel 'using a regular AR barrel'. I wouldn't. If you haven't done it moving a pinned gas block is potentially an annoying project taking real tools and maybe outside help depending on your skill. I have never done a 516 but I have done lots of other ones and it involves punches, fixtures, a milling machine, drilling, reaming and potentially new pins (which who knows if they are available).
2. I wouldn't consider your example of the DD barrel equivalent to this because I can get delivered to my door from a zillion vendors a ready to go barrel with a lo pro gas block already pinned and installed. If SIG or the aftermarket did that I think the OP would be pretty happy. But they don't. That's the difference between 'industry standard' and proprietary. It's for the very same reason that when you head right on over to the official Army TM for the gun you will find that the field replaceable part when you need to change the barrel (that's what the OP wants) it includes the gas block/FSB. No concept of doing a gas block change.
3. Yes I have been vocal about the sig rifle situation, as you would be if you had a huge investment in sig rifles and on many of them they had stranded you without any obvious reason. But I have not made one comment on that issue for this question. And I don't hate 'sig'. that's ridiculous, personal and uncalled for. I own an example (and in many cases multiple examples) of literally everything pistol and rifle they have made and enjoy many of them. That's not hate.
As I said above the OP knows where he stands. Maybe you can offer to swap his gas block for him and all will be good.

This message has been edited. Last edited by: hrcjon,

quote:

Originally posted by hrcjon:
At this point I think the OP has the answer to his question. I can agree with you that you can start with a standard AR barrel and make a usable barrel assembly for a 516 by adding the SIG proprietary gas block. But that misses my point totally.
<snip>

hrcjon ... has anyone ever drawn a parallel between you and a bulldog?

I absolutely get your point, and have gone through the hassle of pinning a front sight base to a barrel ... twice. First time I went to a machinist acquaintance and although his fee was about 3 times what I expected, it was perfect. What I found on the next one was on a used barrel that already had been drilled once for a pinned gas bock/sight. Not all bases are drilled in the exact same place on every barrel, while I'm sure there is/was it's like there isn't a standard spec, maybe just different contractors, equipment age wear, tolerance etc. So the second time I got lucky and one of the barrel cuts lined up perfectly with one of the sight base and the gas port, an I drilled the second myself.

Unless you have equipment to align your block/piston it isn't something recommend to the "average joe" ... even if the gas block isn't also your sight base, you still need to have it properly aligned.