VICKERS MK6B's resto

[Tony Smith]

Originally Posted by David Dunlop

Hi Lynn.

Not to deflect Colin’s Thread for too long, you are correct up until about 1944/45 .303 Grenade Launching Rounds.

Prior to that date, sorting out these rounds is a complete PITA, particularly if dealing with spent casings. Brass cases were standard Ball Cartridges with no special Head Stamps, or crimping. Some iterations had fully blackened, or partially blackened cases and were described in great detail in written documentation, but rarely, it seems, were the differences ever deemed important enough to make the rounds readily obvious to the end user in the field, or at sea. Most of the earlier cartridges were a slightly heavier load of standard powder with a small insert of guncotton fore and aft with a lacquered plug and no crimping. Ballistite and Cordite loads did not gain prominence until the 2nd War when Rifle Grenades, Anti-Tank Grenades and Smoke Grenade usage really evolved, along with Line Throwing equipment for the Navy. I think the Cordite loads were a tropical thing where they stood up better in high humidity to Ballistite.

David

I have a fair collection of .303 Blank and Ballistite, and it seems to contradict what you say.

Pictured below are British, Australian and NZ manufactured Ballistite grenade launching rounds. All are marked on the container and headstamped as H Mk1z. The British and Australin cases are half chemically blackened, while the NZ cases are half Violet resin.

The British rounds are dated Oct 1940.
The Aust rounds are dated Sep 41.
The New Zealand rounds are Apr 42.

The "z" in the name indicates that Ballistite is a Nitrocellulose powder, not Cordite. The Ballistite is not only more stable in tropical conditions, but also provides more energy than Cordite can provide in the case volume.

[Tony Smith]

Originally Posted by Tony Smith

Pictured below are .. Ballistite grenade launching rounds. All are marked on the container and headstamped as H Mk1z.

The "z" in the name indicates that Ballistite is a Nitrocellulose powder, not Cordite. The Ballistite is not only more stable in tropical conditions, but also provides more energy than Cordite can provide in the case volume.

Originally Posted by Tony Smith

.303 Blank cases can be either long or short nosed and are ALWAYS crimped to differentiate them in the dark from Grenade rounds,.....

And what would happen "In the dark" if you used the wrong round?

A Ballistite Grenade launching round used with a Cup Discharger will propel a No36 grenade between 50 to 200 Yards (it has the means to adjust the range). A .303 Blank (which uses Cordite) will only propel a No36 10 yards! This is within the wounding range of the No36. The firing position used when firing grenades means that the firer would not feel the difference in recoil, and in the dark would not see the "flight" of the grenade.

[Tony Smith]

I can't help it!

Geoff Winnington-Ball, when he created this Forum, included some sneaky software called THREADJACKER2000(TM). It causes threads to veer off in random but interesting directions. Do a search for it using the search button to see the results. In a nod to Geoff ( ), it remains an integral part of MLU's program.

We now return you to your regular viewing. Thank you Colin.

[colin jones]

Thankyou everyone for the spent cartridge definition, identification and different types

I am working on the traversing gearboxes and bought some standard gears that are of similar size. Fortunately I have the drawing that is really well descripted and easy to scale.

[colin jones]

Obviously the original was cast but the design is as such that it is relatively easy to reproduce by fabrication.

[colin jones]

The handle on the bottom releases a set of brake shoes which I will find a small set from a motorcycle or similar. It is quite a large reduction of gears so traversing will be very easy. In the manual it says that one revolution of the handle will rotate the turret 3 deg.

[colin jones]

I did quite a bit of searching to find some brake shoes the size I wanted but just couldn't seem to find what I wanted so I decided to make some. As they are very low pressure on little to no speed I thought it would they would be ok.