This replacement barrel from RB Model joins the long list of M2 cal.50 machine gun barrel sets already available with this set containing one M2 cal.50 HB barrel as well as additional parts for the M2 receiver such as the rear firing handles, cocking handle and rear top sights. The parts break down and detail on this barrel set is very similar to that released by armorscale (Set #B35072) a while back. There are some detail differences between the brass parts and etched parts in the RB Model set are not as refined as in the armorscale set.

The set consists of 7 machined brass parts and a small etched fret with 7 etched parts that provide you with a turned brass barrel with drilled out muzzle, the perforated cooling jacket with two small locating grommets either end, the two rear firing handles and cocking handle in brass, as well as the etched barrel changing handle. As with all RB Model barrel sets it comes in a small zip lock plastic bag without any instructions or fancy packaging, just a simple B&W label.


Barrel parts with close up of cooling jacket parts
note raised edges around the holes requiring filing

There is some cleanup needed on the cooling jacket in particular to remove the last of the fine brass burs inside the holes which it easy enough to do as they just fall away using the point of a #11 blade plus there is small raised ridges around the jacket holes which will need to be smoothed with a fine file. The base of the barrel and tips of the firing handles may need a quick file to remove the small bur.

Detail wise the cooling jacket unfortunately is a little undersized in diameter and length when compared to available 1:35 plans and photos and also lacks the two indentations on either side but does have the taper after the cleanup mentioned above.

The front mounting grommet that fits inside the cooling jacket for fitting the barrel also lacks the series of notches around the fitting which are quite prominent on the real barrel and the barrel length is about 1mm short than indicated on most plans.

At the business end the muzzle bore hole is about twice the size it should be and this is quite off putting for those familiar with the M2 barrel.

View of the front of the cooling jacket (left) which is similar to the armorscale without the notches required.

View of RB Model bore hole which is way oversized

Image showing difference in cooling jacket size between the LionMarc (top)
and RB Model (bottom) parts


Assemble is straightforward with the fit of the two grommets to the cooling jacket and the fit of the barrel through these being very precise making for easy assembly of the main barrel/cooling jacket assembly but the lack of details as above is most evident when comparing to photos of the actual gun.

The firing handles fit neatly between the etched brackets with small holes in the etched part and small pins on the ends of the handles for easy location and its best to solder these in place for a robust assembly. A notable omission from the etched handle bracket is the two small thumb firing levers which are on the etched bracket in the armorscale set.

I have fitted the parts to the Dragon M2 cal.50 that comes with most of their current Allied kits and you will need to cut off the plastic firing levers as the etched handle bracket in this set will not fit with these still in place.

The side cocking handle uses that third handle provided but you will need to file off the locating pin from one end for a better appearance and this fits to the etched handle bracket that in turn is glued to the side of the receiver once you have cut away the moulded on detail.

Adding the barrel changing handle will require careful bending around the barrel as this has to extend down from the barrel centre line but the main issue here is the handle and bracket are in flat etched metal and lack any 3D effect that is a common issue with this sort of etched detail.

The rear top sight has to be carefully bent to shape and once the moulded on sight is removed this is glued in place the a separate small etched brass ranging sight this will need care in fitting due to the small size, this small ranging sight incidentally is not included in the armorscale set.

Similar alterations will be needed to fit the parts to other cal.50 kit guns depending on the kit gun being used?

Fitting the barrel to any kit cal.50 MG is easy by cutting off the plastic kit barrel, drill a small 1mm locating hole for the barrel pin and fit in place, all very easy.

Two views of the assembled RB Model barrel and (Dragon) receiver
Note the lack of side recesses and mounting boss on the cooling jacket
the same as with the armorscale cooling jacket.

Comparison views of the armorscale barrel parts,
Note the changing handle has had additional plastic rod added for a better 3D appearance.

Image showing the etched and brass firing and cocking handles
and comparison with the armorscale parts (left)
While this set has additional parts for the firing handles, cocking handle and barrel changing handle the barrel lacks many details such as the correct size bore hole, the notches around the front cooling jacket bracket and the cooling jacket is undersized and lacks the side indentations which are included on most other brass cal.50 barrel sets available.

Despite the extra parts the lack of detail definition on the barrel and cooling jacket puts this set at the bottom rung compared to the others available unfortunately but will improve the look of most plastic cal.50 MGs if this is the only set you have access to.

Recommended with reservations

See a comparison of the available M2 Cal.50 metal barrels

Thanks to Leo at LionMarc Model Designs who now carry the full range of RB Models barrels for the review set.