Tromix .458 SOCOM Sig 556 (pics)

Way cool.

Would shooting that with your gas system on the emergency setting shred the receiver like an m80 in a pop can?

Actually the opposite. With a .458 diameter sewer pipe bore coupled with low 35,000 pressure, actually requires quite a bit more gas flow to cycle compared to a .556 round.

That gives new meaning to the phrase hogging out your barrel....

Interesting how you would hardly notice it, unless you're staring down that bigazz borehole, or worse, on the business end of that barrel.

Your warranty is probably toast, I would conjecture...but maybe worth it anyway once you light that bigbore off! WOOPOW!

Crazy cool, dude.

Tony, How about a range report when you get it finished?

Yeah, I'll post up a range report in the next week or so.

One thing I wanted to mention is the .458 barrel weighs 1.36 pounds, whereas the .556 barrel weighs in a bit fatter at 1.56 pounds, even though the .458 has a larger outside diameter. (.750) The sewer pipe bore really helps to cut the weight.

Tony

Better keep an eye on that, some SOCOM dudes would love to swipe that thing. Sweet!

Badass. 'Nuff said.

Let us know

Tony, be sure to let us know how it shoots.

Any chance this is a conversion you might do for others? I have an extra 556, and a wantin' for a .458.

L.E.E.
www.SwissRifles.com

If all goes well with shooting, which I am very confident that it will, I will then consider making some more. I will probably build a couple more one-offs to make sure I can repeat the job with some sort of speed. It can't take all day to make one, or the price would be through the roof.

I also want to test this 1:14 twist Adams & Bennett barrel and see what kind of accuracy it will do. When I was building the .458 AR's, I used 1:18 Pac-Nor Super Match barrel blanks that run $280 versus $80 for the A&B barrel.

The conversion is actually no more difficult to do on the Sig than it is to do on an AR. The AK and Mini-14 take a pile more work.

Tony Rumore
Tromix Corp

I am constantly amazed at the skilled folks on this site and their willingness to share with others. Great job Tony and hope everything functions well.

By the way, how do you think the stock will hold up to the increased recoil? I hear your .458 round packs quite a punch.

That's a good point about the stock. The old CAR stocks had a bad habit of auto collapsing when subjected to the .458.

I guess we'll see about the Sig Clasic shortly. If it fails, I can always swap it out with one of my other Sig lowers that takes the AR stock interface.

Tony

That looks pretty slick Tony, will you post a range report on it?


Maybe it's just the angle of the picture you took but that BC looks like the milling is lop-sided. :?

TonyRumore said:

That's a good point about the stock. The old CAR stocks had a bad habit of auto collapsing when subjected to the .458.

I guess we'll see about the Sig Clasic shortly. If it fails, I can always swap it out with one of my other Sig lowers that takes the AR stock interface.

Tony

Click to expand...

You can also swap the stock for an OEM 550 SAN stock.

The bolt just looks that way in the pic. I indexed it dead nuts on the money using a four jaw chuck.

Tony

I have to tell ya, that is the coolest thing I have ever seen. I went to an RA XCR because I wanted a 6.8 SPC. Had I known something like this was possible with my sig, I wouldn't have sold it. I loved it, just not the cartridge. Nice work.

Time to get another 556 rogue and have Tony hook you up

I knew he was going to do something that would cause the Swiss to say "those #*@*ing Americans" :lol:. Tony, I think your being bit of a teasing ass clown by posting pics without the videos :lol:. You guys should take a moment and look at his "project guns" page, you'll see why I was expecting "American kick ass ingenuity". Seriously, I want vids, like now, please.

Any more news on this?

Range report? When do you start taking orders

Holy Crap! Big Bad WANT!!!!

That is the coolest! Yes I'll buy an extra 556 if you decide to do this for others!