introduction

The Ural 4320 high mobility truck was introduced in 1976 as a diesel development of Ural 375. Being a replacement it took over all the roles its predecessor has been used for (and continued to be used concurrently in until completely worn out). One of the numerous versions was the BM-21 “Grad” (“Hail”) 122mm multiple rocket launcher with a traversing and elevating pack of 40 launching tubes in the back. It was directly transplanted from the 375.

Various derivatives of Ural 4320are still in production today.

The Trumpeter kit of the Grad MRL has been introduced earlier in 2013. It represents a pre-1993 vehicle with short “nose” for KamAZ-740 V8 diesel, revisions from 3 to 10. (In 1993 the KamAZ engine plant was completely destroyed by a massive fire. To avoid disruption of military vehicle production, the 4320 – amongst many other – was hastily re-engined with YaMZ-236 (V6) and YaMZ 238 (V8) diesel powerplants. This necessitated a longer engine bay, which remained in production even after the KamAZ plant was rebuilt.) You will also notice that the side mirrors are mounted on a single-point bent rod, rathen than the later U-shaped mount.

construction

Instructions consists of 30 construction steps and a painting guide. To this reviewer’s pleasure parts are clearly labeled, steps appear to be in logical order and almost lacking errors. Please make sure to observe the drive shaft orientation as shown in the booklet – details are molded in a way that allows their fit in one way ONLY.

Step 1 – assembling the chassis. You will notice that the radiator group is integrated with one of the spars and is glued here. Almost right behind it is part E41 – the notch in its middle should point to the rear and up. It’s one of the attachment points for the engine block. My advice: align and glue all the spars to one of the girders first, then attach the second one.

The small sub-assembly in the lower right of step 1’s diagram is the engine alternator, used in the next step.

In Step 2 you will assemble the engine and gearbox. They are both rather inaccurate depictions of the real deal, very under detailed and with mediocre fit – oh well. Also, on the real thing the gearbox is bolted directly to the engine block, so that short driveshaft is pure fantasy.

Step 3 – mounting the engine, gearbox, transfer case, front bumper and the rear spring packs. My recommendations:
- I would add part E25 in step 1,
- test fit the transfer case. Check the fit of its flywheel (parts E2 and E45) against the chassis (I had to trim E2 to have it fit).
- leave the engine, gearbox and transfer case off until step 5.
- simply push the spring packs in place without gluing them and don’t bother with aligning – adding the other suspension parts will do that for you.

Step 4 – assembling rear axles. These are NOT identical and I’d suggest you label each sub-assembly accordingly. Parts have aligning pins that will help you add the proper parts where they belong.

Step 5 – rear bogey and driveshafts. Start by adding the third axle (assembly D-D), then driveshaft E12 and finally, the second axle (assembly C-C). Next add driveshaft E9 to the second axle, then to the transfer case; set the transfer case in place on part E25. Now that you made sure there will be NO bent driveshafts, suspension and chassis, you can add the gearbox and engine, which are NOT structural assemblies and will be hidden from view anyway.

Parts E8 and E11 are placed asymmetrically – only on the right-hand side – and have the corresponding mounting notches.

Step 6 – battery box, fuel tank, front springs. The fuel tank requires some careful sanding to prevent losing detail – retaining straps are molded on. Check the fit of the sub-assembly against the girder – I had to shorten the locating pins for the tank to fit properly.

Step 7 – mounting the front axle. To fit the two shock absorbers (part E12) to the U-shaped parts E10 and E7 as shown – please cut a sector off the top of their circular mounting lugs.

Step 8 – front wheel assembly. Just like on the real thing the wheels can actually be turned if the modeler so desired. That would also affect the position of the steering rod – nice! Trumpeter switched the wheel assemblies for left and right (the only real mistake in the instructions).

Wheels and tires (steps 8 and 9). Observe the “direction of rotation” arrow on the tires – the “elochka” (herringbone) thread pattern should always point downwards when looked at from the front. Note that the tire material is resistant to modeling glue.

Step 10 – adding wheels, driver’s seat and rear bumper. The two PE details have NO markings to help you with bending. Simplest method for measuring where to bend the PE: mark about 0,5mm after the bolt heads, divide the rest of the parts’ length in 3 equal parts and bend at the marks.

Step 11 – cab floor and rear wall. The way you glue these two sub-assemblies together will determine the shape of the cab. If you just clamp them together the rear wall will be too inclined to the front.

Step 12 – dashboard. Two funny moments here:
- the instrument panel decal goes over the separate switches you just installed per instructions (parts A23, A24), so you can cut off the offending portion of the decal and just paint said switches.

- the launcher control box in the middle of the dashboard can be posed open without its lid (part G12) – there are details molded in the middle part (G19). Depending on the vehicle the box halves (part G12 and G19) can be black or camo color; control panel is black.

Step 13 – air intake, cab windows, doors and steps. The air intake assembly (parts B18, B19 and B20) should be mounted slightly angled forward. Amongst other things this allows for the right-hand mirror to be positioned properly. The circular detail below the intake is the grounding socket used when the machine will be fired.

Door halves are actually a pretty good fit. If you clamp them too tight they might bend so be gentle. The various handles have either too long or too large mounting pins –test fit before you add them to the doors. I painted mine chrome as they appear on new vehicles.

As the steps on either side of the cab are attached using only a single surface, I would recommend test fitting the steps with the front cab and against the corresponding fenders (no earlier than step 15).

Note all windows have black rubber seals, which Trumpeter has conveniently molded as raised detail – this will greatly simplify masking. Clear parts are flat just like on the real thing, distortion-free, and fit pretty well in their recesses.

Step 14 – adding the doors. Trumpeter actually has the hinges in the right place and raised enough so you can mount your doors open. I did manage to shave the hinges in the kit off, so they were rebuild using round styrene stock.

I glued pieces B2, B3 and B4 together and to the cab front at this time, using thicker glue (Humbrol Poly Cement). As there are NO locating tabs to align them – I used the bare chassis as a jig to put them together properly. Remove the locating stub on part C39 – it is about 1,5mm too far forward and will lift the rear end of the cab if you didn’t.

Even if you glued the engine and transmission you can still maneuver the whole cab assembly around them and set it in place (positive effect of the lack of detail on the engine block).

Step 15 – fenders. What I did was gluing parts B16 and B17 directly to the sides of the engine compartment, before adding the B23/24 and B22/25 assemblies. The locating tabs on parts B24 and B25 had to be removed – the corresponding mounting slots on the fenders were about 0,8mm too far back.

A few words about the lights: depressions for the headlights’ reflectors are too shallow. The parking lights/turn signals above them have a clear (white) lower half and clear orange upper half. Turn signal repeaters on fenders are clear orange. Roof lights (switched on when the vehicle has something on tow) can be transparent or clear orange.

Windshield wipers: their locating pins are way too short. You need at least 2mm extensions to get the wipers to sit flat against the glass panels as on the actual truck.

Step 16 – mounting the cab. The kit needs 10 more copies of part PE9 to replace the barely-molded ones on each side of the hood/bonnet.

Step 17 – exhaust. I omitted part G10 altogether. Instead I cut off the locating pin and drilled out the cone on part G38. This provided a much more realistic finish of the part.

Step 18 – spare wheel assembly. Part PE6 is too short, so you can use the spare part PE3 instead (there are six PE3s on the fret and only 5 are used as per instructions).

Step 19 – I’d recommend installing the spare wheel frame after the toolkit assembly is attached to the chassis (step 23).

The odd-looking details on both sides of the cab are control light blocks (top to bottom: blue, green and red). These were used to visually indicate the vehicle’s readiness to fire to the battery commander.

Steps 20, 21 and 22 – toolkit. Pretty straightforward if you follow instructions. The two cylinders at the top of the assembly were actually boxes as well, not pressurized tanks.

Step 23 – mounting the toolboxes and mirrors. Both mirrors have a black rubber seal around the edge – it can be seen on both the front and back. The non-mirror reverse could be black plastic, painted camo color or left natural metal.

Step 24 – launch pack turntable. If you’d like to set your launcher at a different angle – this is the moment to do it.

Step 25 and 26 – additional details on the turntable plus building up the rocket pack. What you will undoubtedly notice is that the clever engineering employed by Trumpeter minimizes seam exposure here. On the tube exterior there are subtle hints of the grooves that help the rockets spin and thus be more stable in flight. The joints between the three plates on the missile pack rear (K13, K14 and K15) required a bit if putty on my example.

I left the rear caps (parts M14) off for easier painting. However, when trying to mount them at the last step of construction I discovered they interfered with the electric starting socket (parts M12), so if you want your caps on – following instructions. The caps themselves are of an early type, these are no longer in production or use, and are replaced with a much thinner, flatter design with 6-spoked raised detail.

Step 27 – aiming device. Neither separate parts diagram, not the image of the complete assembly gives enough information on actual part placement and color, so pictorial reference is a must.

Step 28 – launcher base, mud flaps and tail lights. The base is a pretty simple affair, and it lacks the bolts that attach it to the chassis. Mud flaps: the wide flat areas on parts H14 and H15 are actually rubber, so you need to paint it the respective color. Tail lights: outer 40% is clear orange, the rest is clear red (there are actually lines on part GP4 you can use as guides). Part GP11 must only be present on the left mudflap – it’s the light illuminating the license plate. It’s either camo color or natural metal. The reverse gear light on the right fender should be square-shaped and at least twice as big.

Step 29 and 30 – attaching sub-assemblies. The launcher can be glued in the firing position – rotated to the left side of the vehicle. As noted earlier the engine is not quire the real thing, and the characteristic hinges on the inside of the hood are missing, so it is best left closed.

conclusion

To this modeler Trumpeter’s BM-21 on Ural 4320 chassis is a welcome release. It certainly is up to contemporary standards for building an out-of-the-box model that does pretty closely represent the real thing without modifications, and does not require a lot of expertise to build. Clever parts breakdown eases assembly, fit is good to very good. I am particularly fond of the fine representation of the OI-25 tires.

My expectations of future Ural 4320-based vehicle releases from Trumpeter: a proper engine with exhaust plumbing, gearbox, and a compressor. The lack of compressed air tanks, a few prominent valves, pumps and other details on the chassis is hidden because of the Grad’s particular details, but would stick like a sore thumb on the cargo version. A version of the chassis with winch and the long nose would also be nice.

Highly recommended.