Introduction: SIG550 (StG90)

Picture of SIG550 (StG90)

Small Arms: Visual Encyclopedia by Martin J. Dougherty states this of the SIG550 (StG90): "Adopted by the Swiss Army as the StG90, the SIG 550 is in many ways a traditional design, but much careful thought wen into is 'usability.' It has spawned a family a variants including short-barreled carbine versions." I would say that is is pretty fair to say, as even the K'NEX version of this gun is highly "usable."

It is, on the whole, a handsome gun. With it's epic stock, nice mag length, and perfect handle degree,  I would say that it is a great gun. The sights are great, and the gun is very sturdy. At least one other attempt, to my knowledge, was made at this gun, and I would say that dr. richtofen did a fairly good job at modeling it. Mine is just one inch over the actually length, mine being 40 in., and the original being 39".

My reason for building this was simple...I could not decide what else to build. I was not in the mood to build another sniper rifle, as I just posted my M14/M21. I did not want to make another one of my trademark firearms, as I thought you guys might be getting bored of those. So, seeing this in my Small Arms: Visual Encyclopedia book, I built it.

Now, to the more interesting fact, it's range. This gun, shooting from a muzzle loaded round, pointing (almost) straight forwards, fired 52 ft. Pointing it 45 degrees into the air made it shoot 86 ft. I was quite happy, as you might imagine, to find this out. Now, it must be admitted that I was not firing a bullet from the mag, but I was out side, and since this gun shoots dark grey connecters with a green rod attached to it, I did not want to lose the round.

-Great range: (52 - 86 ft.)
-Great looks (IMO)
-Nice stock (credit to Blue Mullet 2's SIG552)
-Nice sights
-Kinda piece consuming
-Almost the same length

Well, there you have it, my SIG550 (StG90). What do you guys think?

-The Red Book of Westmarch


Senior Waffleman (author)2013-05-27

Looks great! Keep up the good work!

Thanks bro. =D

Sharir1701 (author)2013-07-28

Aww man that's really cool :) An updated version of one of my favorite guns, back from my MoH2 days :) Awesome, looks good, nice work. Keep it coming man!

Thanks bro. =D

TheAwesomestDude (author)2013-05-24

btw I redoing my SCAR for the last time (this is the 5th) as I just remembered how I did my third

Sounds great, does that mean that your other projects fell through?

no =P I have a lot of knex pump action shotgun is complete and so is a breech loading AR and about 1/3 of the way done with the SCAR

Good, good. I cant wait to see them. =D

and a handle mag removable mag gun =D

Cool. How is that coming along?

actually pretty good =D I also forgot to say that the breech loader is modeled after the BR from Halo 4 and I am working on a small ball machine- they always have fascinated me

Sweet! Common, post them. =D

in a week kinda busy because of finals but i only have 3 days of school left!

charlie-on-our-6 (author)2013-05-28


Johnhall14 (author)2013-05-25

Awesome, I see your enjoying the book =D

I'm not just enjoying it, I LIKE it! (since "love" and "like" don't mean the same thing)

lol =P Did you see the automatic Japanese anti tank rifle in the WWII part of the book, You should try making one.

YES, that would be awesome! XD, but kinda hard.

It would be awesome =D well I'm trying to update my mp5k and I know you mentioned something about the top row of connectors being to wide. I tried to make that area thinner but its not working so I'll be going back to the normal for that part. I'm going to be making the mag use green rod ammo to get a more realistic size and see if I can make the sights better,still trying to make it use a folding stock(nearly impossible with the pin)

You are seriously taking another whack at that MP5K? Have fun. =D Well, if you think that it is about the right length, that is the best you can do. I just made a remark that I think it looks a little wide, but it is not really THAT big of a deal.

AUG-5OM3 (author)2013-05-26

Wow dude looks great! What are you btw a knex gun machine? you keep posting about every two days =D

Thanks bro. =D Well, I have had some little time, and this gun was rather easy.

Okay =D

Thanks man, I would have to agree that it is not perfect.

TheAwesomestDude (author)2013-05-24

really nice!

Thanks bro. =D

your welcome =P

dr. richtofen (author)2013-05-25

Looks great, again ;P Only thing I think is a bit less, is the front sight. Still looks fantastic overall, and a lot better than my old SIG

Thanks for the complement, it is good to hear it. Yeah, I can never get the front sight how I want it. I would not say it is better than yours, just different.

You're welcome :D

JonnyBGood (author)2013-05-25

Nice! Looks hefty and long, but it looks just like the picture. Good looking gun though.

Yeah, it is rather hefty and long, but that is what the original looks like. Thanks man. =D

No prob. =)

didexo (author)2013-05-24

Cool :P

Thanks bro. =D

No problem.

sandroknexmaster (author)2013-05-25

Nice! I like the stock.

Thanks bro, yeah, me too. =D

Vaetheon (author)2013-05-25


Thanks bro. =D What are you working on ATM?

Knex.X (author)2013-05-25


If I were to do that, I would have to mess up all the mech and internals, so I just chose not to. Thanks, I am glad you like it. =D

FlyingFish10 (author)2013-05-25

If you were an inch off, why didn't you take a connector off of the fake barrel? Anyway awesome as always.

Well, you see, if I took off a length off of the barrel, it would look disproportionate, so I chose just to leave it a inch long.

About This Instructable




Bio: K'NEX gun builder here at Instructables. More or less retired from the community, but I still pop in now and again.
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