Stupid Bitz Tricks #2: Sentry Gun


I’ve wanted a couple of the Forge World Space Marine Tarantula sentry guns for a while now, because I’ve had a thing for sentry guns ever since watching the director’s cut of Aliens. In that movie, there were a couple of scenes in which the Marines deployed some UA 571-C sentry guns and used them to fend off the xenomorph onslaught. However, I have some problems with the Forge World Tarantula models, namely the facts that they’re too expensive at the current GBP-USD exchange rate, Forge World doesn’t deduct the 15.5% VAT for overseas customers, and I’d actually like something a bit smaller anyway. So, I decided to check my bitz box and see if I could make my own.

The Prototype

I found enough of the right bitz, and this is the result:

It’s small, looks the part, is surprisingly easy to make, and can be made solely from leftover Cadian and Space Marine bitz.


The next two photos illustrate the bitz used and where they go. (Click on the pictures to see them at full size.)

The Design

I chose to use Cadian heavy weapon bitz because I wanted the sentry gun to be plastic and fit in seamlessly with my GW plastic figures. The main body of the sentry gun is a lascannon with the entire barrel removed, and mounted on a tripod. The front half of the sentry gun is a heavy bolter with everything behind the ammo feed/ejection ports removed. I took a Cadian grenade launcher arm and removed everything except the drum, then cleaned it up to serve as the ammunition drum for the sentry gun. The drum was glued to the feed port of the heavy bolter.

At this point, the sentry gun looked a little unbalanced, so I added the muzzle brake from an autocannon to lengthen the barrel. I also sliced off the carrying handle from an autocannon ammunition drum and glued it to the top of the lascannon body. Next, I needed some sort of sensor cluster on the left hand side of the sentry gun in order to balance out the drum and make it look more like a sentry gun, so I rescued the grenade launcher’s barrel and shaved it down to serve as a large sensor housing. The rail along the bottom of the grenade launcher barrel makes a nice mounting point, so I applied glue to the bottom of the rail and attached it to the side of the lascannon body. The targeter from the heavy weapon sprue was glued above it, along the angled portion of the lascannon body.

I liked the way it looked, but it still didn’t quite say “sentry gun” to me yet. I decided it needed two more elements: some sort of control box that would make it look like a remote weapon system, and the sensor I made from the grenade launcher barrel really needed a lens in front. I went through my bitz box again, and found a Space Marine targeter and a baggie full of spare voxcaster backpacks. I sliced off and glued the front of the Space Marine targeter to the grenade launcher barrel, and it finally looked like a proper sensor. I cut off the bottom half of a voxcaster backpack and removed the long antenna from the top. To form the control box, the bottom half of the voxcaster was glued to the right side of the lascannon body, behind the ammo drum, and the antenna was glued to the control box to finish it off.


You can make a sentry gun out of one $13 heavy weapon team box and leftover bitz from a box of Cadians, and still have enough bitz left to make a missile launcher team and a mortar team. Use the kneeling legs for the mortar team, and the missile launcher bitz work with regular standing Cadians pretty nicely. You’ll use the included 60mm base for the mortar team, and the sentry gun will need a spare 40mm base. If you buy the $35 heavy weapon squad box, you’ll get 3 sentry guns, 3 missile launchers, and 3 mortar teams out of it.

I’m thinking about using the leftover sandbags and stuff to set up a sentry gun control station, with some sort of scratchbuilt command display, a communications unit, and a couple of kneeling guys on a 60mm base. One of those could control multiple sentry guns, and it’d look pretty cool on the tabletop.

Looking at the completed sentry gun model the next day, I think I’ll do it a bit differently next time. The heavy weapons sprue has two autocannon drum carrying handles, so the next sentry gun will have two carrying handles on the top of the body, along the angled bits of the lascannon body, which would make the sentry gun look like it could be carried by a couple of guys. The smaller targeter from the heavy weapons sprue would be moved up top, between the carrying handles and close to the front. I’ll probably leave the larger sensor on the left side of the sentry gun exactly where it is to visually balance out the drum on the right side.

5 thoughts on “Stupid Bitz Tricks #2: Sentry Gun

  1. rustynail456

    Those look great…I hope you magnitized the weapons so you can mount it on vehicles too!
    I magnitized all my heavy weapons so I could mount them on half tracks and tank ect…

  2. Mel Ebbles

    Thanks! I didn’t magnetize it, since it was a prototype. I might magnetize them in the future so they can be swiveled, though.


  3. Anonymous

    The only problem I can see with them is that the ejected casings would hit or obscure the sensors, other than that they're fantastic!

Leave a Reply

Your email address will not be published.