I spoke to Maxim this morning on chat, via their website. They said, "any brace fits the (P556) pistol if you purchase a compatible buffer tube."

Since the P556 doesn't utilize a "buffer tube" (at least not like an AR), how does this work? I've searched and searched and can't find anyone that's done this. I apologize for my ignorance in this matter.

Anyone know where I'd find a compatible buffer tube for the P556?

Thanks.

- LZ

Fullmann brought up a good point I forgot about the 2 styles of 556. We need to know which model 556 you have.

Which end cap does your gun have?

Early model 556s utilized an AR style buffer tube.
It has been a long while since I have seen one in person so my memory may be a little fuzzy. But those pistols I believe had a pretty flat endplate with a button like cap that unthreads and a buffertube threads on there.

There is also the 556 model that I have that has a thicker endplate and a little wing on the side with a pin holiding it in place.
If you have this style you will need a 556 to buffer tube adapter like this.
https://ddles.com

Of course using a folding buffer tube adapter with the PDW style brace you will not be able to fold it.

Okay, here's a few pictures of my P556 . . . . . . .




I believe mine is one of the older models as I waited quite awhile before eventually purchasing it.

- LZ

Pretty sure you just unscrew that cap there on the end and you can thread on a buffer tube.
No adapter needed for your model.

Correct,unless you have a need for a 1913-picatinny interface. If so, check out my post above. 1913 gives one a lot of options, especially if one owns several rifles &/or pistols with that interface including other platforms.

BTW, my cap did not come easyly. Your cap may end up as scrap.

Good luck,

yeah, either the KNS or the SB folding adapter should work. then any brace that fits an AR tube or picatinny are available to use.

ill reinforce what ambush stated. i believe mine had thread locker on it. needed a heat gun and some patience.

also keep in mind about thread locker; constant pressure is not your friend. Put a spanner in the holes and smack with a hammer. It will crack the thread locker. If you try to torque it off, it will fight you.

Man!! You guys aren't kidding. This cap is a PAIN to get off indeed.

- LZ

Now you tell us... Actually PGT, thank for that piece of knowledge, for next time. BTW, I have been using Vibra-Tite VC-3, when I think I may need to make adjustments. This is what America Defense Manufacturing requires to maintain their warranty.

SIG customer service dude said he did believe there was thread locker, so I believed him. I ended up using a big vise-grip with curved jaws. That and my manly 185 lb frame took it down. My wimpy spanner did nothing but help the TL resist and deform the holes.

threadlocker needs to hit 500F before it will be overcome by heat. If you don't have a laser thermometer, you can sometimes see the threadlocker "smoke" or even hear it crackle.

I only use heat as a last resort especially on alloy items.

Check these guys out.

https://star15.com/parts-acces...-receiver-block-arrb

https://star15.com/parts-acces...-fsm-ar-without-boss

quote:

Originally posted by LZ_226:
Thanks for the suggestions so far.

"PGT" Do they make a folding variation of the pistol brace?

"Black92LX" you have me intrigued. You're saying that with some sort of adapter I can use the SB MPX Brace



on my Sig P556? How would the receiver accommodate the MP-5 style rails that are used on this brace?

I would love it if there were a way to do this. But, I can't imagine it working since the receiver hasn't any groves in it for the rails to slide in and out of.

Oh it works ... beautifully.



Mine has gone through evolution many many times ... It was an early one, I brought it home looking like this



at one point it used the ACE hinge



Then I bought a "Classic" lower for it, at first with an M4 stock adapter from DDLES. At some point it got a SiCo mount to replace the SWAT muzzle break and later the Xi lower and the last noticeable modification was the MCX adapter and stock and a SWAT hand-guard. Lastly and finally I came across a gas valve with a suppressor and not drilled at all for a single shot setting and I think I'm finally done.

I think if I were to ever get another I'd use the Ace hinge with a tail hook brace.