*Disclaimer: To avoid any confusion, this is a replica prop for the purpose of cosplaying and displays only. It does not fire any form of ammunition and cannot be modified to do so. I do not condone the creation of working firearms as it is dangerous and in most places an illegal practice. When cosplaying with replica firearms at conventions, including ones with fictional designs, ensure it is within the rules of both the convention and your local district, and you have taken the necessary precautions to identify it as a replica (Such as fluorescent tape around the muzzle).*
In this tutorial I will list the steps I took to create the anti-materiel sniper rifle that features in Halo Reach. While it will be unable to fire anything, a simple trigger mechanism will provide a tactile feel for realism, the bipod and stock will be adjustable, the magazine will be removable, and the charging handle can be moved back and forth.
- 45mm x 145mm Timber (Approx 2.5m)
- 20mm wood (Approx 70cm x 10cm)
- 10mm wood (Approx 2m x 20cm)
- 3mm MDF (Approx 50cm x 10cm)
- 25-35mm Diameter aluminium tube
- 20mm Diameter aluminium Tube
- 38mm wide cabinet hinges (9 used)
- M14 Socket cap bolt
- Wood glue
Step 1: Wooden Blocks
To measure the dimensions of each section and determine the positions of each surface feature relative to the edge of each wooden block, I downloaded a PDO file of the rifle and opened it in Pepakura Designer, where I could use the "Measure distance between two points" tool to sketch out some rough blueprints.
The dimensions I used for the lower body of the rifle were:
- Lower body: Length = 903mm, Width = 45mm, Height = 150mm
- Middle body: Length = 582mm, Width = 78mm, Height = 40mm
- Upper body: Length = 582mm, Width = 70mm, Height = 38mm
- Stock: Length = 35mm, Width = 70mm, Height = 222mm
- Barrel shroud: Length = 65mm, Width = 65mm, Height = 328mm
- Barrel join: Length = 65mm, Width = 58mm, Height = 144mm
- Muzzle brake: Length = 158mm, Width = 94mm, Height = 73mm
For clarification, the lower body is the part including the forestock, grip and butte. The upper body is what the scope is mounted on, and the middle body fits between the two. The barrel join (Couldn't think of the right name) connects the barrel to the tube below it.
The barrel shroud and join both had dimensions exceeding the 45mm width I was using for most pieces, so I glued some 20mm thick wood to them to reach the necessary 65mm and filed them down after waiting for the wood glue to set. The muzzle brake also exceeds the 45mm minimum dimension, but I had a 95mm x 95mm post which I cut a chunk out of instead. If you have wood with larger dimensions you can cut it down to size for any of these pieces.
The timber I used had been outside for over a decade, so it wasn't in optimal condition, although it was fine just below the surface in most areas.
Step 2: Trigger Mechanism
This doesn't have to be too neat, since most of it will be concealed anyway. I used some scrap aluminium with a hole drilled in the top to act as a pivot point, then epoxied a nut between the two sides where the hole was located and a small backward facing bolt to act as a guide for the spring.
When a bolt is threaded through to act as an axle, the nut prevents the trigger sliding or twisting, and provides a smooth oscillating movement. A clothes peg spring should provide just the right amount of opposing force when you pull the trigger; roughly 3-4x more than an Xbox controller's trigger, although you can increase this by using a stronger spring, or moving it further from the pivot.
The holes for the spring and trigger to fit in were carved out using a rotary cutting tool.
Step 3: Aesthetic Side Panels
I used a combination of plywood (12mm) to produce the side details above the foregrip, and stacked layers of laminate MDF floor boards (3mm) to create the angled panels on the stock. To save time, I held them in place with panel pins and wood glue, as they don't require the same strength that screwing the other sections together needed.
For the deeper details I used a router, although most of the cosmetic grooves can be engraved with a high speed rotary tool (E.g. on the butt of the rifle).
Step 4: Barrel Attachments
The muzzle brake, joining block, vented shroud and the area above the magazine all require a hole the same diameter as the barrel. You can use a short screwdriver-bit extender to drill the 33cm hole through the shroud from each end, although the barrel must extend about 12cm behind the ejector slot to allow the charging rod to slide all the way back. Since this can only be drilled from one end, the spade drill bit will have to reach 40cm, so a 30cm screwdriver bit is recommended (See intro page for link).
When drilling these holes, it's important to avoid allowing the drill to twist or change angle. After about 10cm, it's easier to verify you are drilling in a straight line by aligning the shaft of the drill bit with the centre of the hole, but initially you should try using a 2-axis spirit level to verify the drill is horizontal while looking at it from above, jury rig a laser pointer to it, get someone to check one angle while you check from another, or use a mirror to check both at once.
Use pilot holes to guide the spade bit, as standard drill bits require less force behind the drill, and so are easier to control. Another benefit to drilling the hole part way from either end is that even if they don't meet perfectly in the middle and you have to file some of the centre away, it will still be straight, as the opening and exit holes determine its angle in relation to the barrel. If you were to drill it all from one side and it was off centre, you would have to file away much more material, and you'd be left with an oval shape hole on one end.
Step 5: Telescopic Scope
Although buying a scope doesn't actually save much time compared with making it from scratch (It's only the front that's visible), it adds even more functionality to the rifle, and eliminates the need for LEDs to produce the illumination effect. The other bonus is that when coupled with a Picatinny rail, it makes mounting much easier, although you could just buy the rail and a pair of brackets for under £10, and make a cosmetic scope from scratch.
Step 6: Cartridge Loading Chamber / Ejector
With the barrel inserted into the body of the rifle, mark a dot on the barrel as far forward as the charging handle can slide, and then another dot approximately an inch behind the back end of the magazine slot and draw a line between them. They should be about 16cm apart. Cut a section of tubing that is another inch longer than this (18.5cm).
Glue a wooden dowel into the 18.5cm tube to provide stability for the bolt; the dowel doesn't need to reach the ends, just ensure it's at least 5cm long and sits flush with the front of the tube. Insert this tube into the back of the barrel so that the ends of each are aligned, then drill a hole about 6mm from the end of the line you drew using a 12mm drill bit, so the edge of the hole meets the end of the line. This should also drill through the inner tube and dowel, although make sure you stop drilling as soon as you touch the opposite side of the tube.
Remove the inner tube. and continue to drill holes along the line then file the gaps away, and after some work you'll have a 16cm long oval hole. A milling machine would cut a cleaner slot, but I was limited to just drills and files. Clean out all the metal shavings, re-insert the inner tube, and thread the bolt into the hole you made in the inner tube, and the chambering mechanism should be complete.
The left hand side should only have a narrow opening to allow the bolt to slide back and forth. I used a small section of aluminium sheet to cover the gap, and used bent over tabs and hot glue to hold it in place. On the other side I used a mirror image of the left side but without tabs or a slot, and added two of the 38mm hinges to allow it to be opened and closed.
Step 7: Magazine
I intended for the magazine to be very rigid but also hollow, so it could be used to store things like bullets, or even be retrofitted with a sound system for audio effects. I constructed it from 1.5mm aluminium sheet after creating a test template from card.
Cutting the overall shape out was easy using a pair of cheap tin snips. I left 3 tabs to fold against the wood to provide a strong fixture point for the wooden base. The trickiest part was bending it: The first few bends went without a hitch, I'd sandwiched the sheet between two blocks of wood in two separate vices, and applied force close to the base of the sheet to produce very sharp bends. The parts that almost defeated me were the bits that needed an offset bend, with two 45° bends in opposite directions about 5mm apart.
I eventually managed by clamping additional thin metal rods in with the wooden blocks so I could clamp it without compressing and unfolding the bends I'd already made. I'd recommend just leaving the front half flat and instead gluing a wide strip of MDF against the metal to simulate the protrusion. The final bend where the metal wrapped around on itself was at the front of the magazine, and I glued in a block of wood so I could pass two screws through both sheets and pin them against the wood.
I'd managed to match the shape of the metal with the profile of the wooden base pretty well, but to fill in any gaps I just used plenty of wood glue.
Step 8: Bipod
The bipod comprises almost entirely of MDF, although I later added some metal parts for strength. It hinges around a "C" shaped metal rod taken from a fold out washing rack, which I'd bent into four 90° corners, and slotted into a hole I'd drilled into both sides of the rifle just in front of the fore grip. The two ends meet at the top, and are prevented from pulling apart by a plastic sleeve that I'd heated and threaded over them (After threading the bipod halves over each end).
The bipod legs are made up of the pivot, the leg and the foot. The pivot is practically two identical layers of MDF on top of each other with a hole cut in one end. The legs are similar, but the top layer is about 5mm narrower on each side, and a channel running down the middle for a metal strengthening rod to be glued in place. The feet are a single layer with two prongs facing forwards. They were all adhered with wood glue, and fixed to each other using 38mm butte hinges.
Where the hinges are bolted to the leg, I added a small strip of metal to hold the reinforcing rod down in case the glue started to fail. On the side of the hinges attached to the pivot section I added a simple metal bracket to stop them splaying outwards along with the legs, but in the centre of the legs I added a folding hinge to prevent them opening to more than a 90° angle, which acted as the perfect spot to mount a clip to hold it in a retracted position.
Step 9: Scope Shroud
The complexity of the shape made it easier to follow a Pepakura template and cut out parts accordingly,
I reinforced the card with wood pillars, additional card layers, aluminium "ribs" and eventually expanding foam. The end result was very strong, but still not a perfect fit.
It's be more effective to customise a scope shroud from scratch based on the scope you have, or make a non-functioning scope so you can just fit a coffee tin over the end to use as the front lens.
Step 10: Painting
Painting such a large object means you can afford to make mistakes without them showing up from a distance, so it's relatively easy for even novice painters.
Give everything a couple of coats with grey primer, and spray the magazine separately. The rifle uses about 5 different shades of grey which can be achieved using only combinations of black and white, and one which needs a fair amount of blue adding. The other colours you'll need are yellow, red and silver (Red for the "FIRE" selector and to add to the yellow band to make the colour more orange).
Use masking tape or a narrow brush to finish straight edges, and water your paint down to about a 1:4 acrylic/water ratio. If you're using an airbrush this will help reduce the viscosity and improve the flow rate, and if you're using a paint brush it'll prevent bristle streaks forming.
For the grime wash, use almost double the ratio of water to black or brown acrylic, paint a line along any recesses or grooves and wipe it around with a sponge or wad of dry tissue to diffuse the edges. Repeat if necessary. or use an airbrush with very low flow rate of paint.
For the silver dry brushing, just make sure you have minimal amounts of silver acrylic on the brush, and add it more heavily to corners and the edges near the corners. The more easily the corner could be knocked or abraded, the more silver you should add.
Once finished, give everything light misting of clear coat to seal it in and protect the paint work, particularly if you painted onto areas that might easily flake off (Like the thin laminate panels I used for MDF).
Step 11: Completed Pictures!
Voila! Here is the final product!
It's pretty heavy at around 8 or 9kg, so I'll be making a much more manoeuvrable costume to accompany it in place of my Mjolnir armour. Otherwise, it's one of my most successful replica props yet!
Feel free to comment if there are any details I've missed out, or if a particular step needs clarifying.
Thanks for checking out my instructable!