DT Light Machine Gun

**GasMasksUK** · 09-14-2010, 09:20 PM

Thanks for that Ade, I've just had a look through some old photographs and video's of me and some other guys at cadets and it does fire from an open bolt

And I've seen that exact picture a few times before, even at a presentation we were shown before going on a training exercise with the army involving higher calibre ammuniton

Thanks

Danny

**HARRY THE MOLE** · 09-15-2010, 10:14 AM

Hi Danny,
The Bofor's was a great weapon to fire. We had Hawker Sea Fury's towing the target, and the planes belonged to a woman by the name of Baroness Reibnitz von Thyssen - all the pilots were women as well. Our Battery (9 Plassey Battery) later changed to the Rapier missile system. We were the first unit to have these weapons, and were in effect the 'trials unit'.

We went to the Hebridese for a live fire exercise. The target was towed by a Canberra bomber about a mile out to sea. On the target was a device called a R.A.M.D.I (radio active miss distance indicator). I was sat on the sand dunes waiting my turn at the controls and just watching the shoot. A friend of mine sent his missile towards the target, these things flew at mach 0.9 and were a little under 5ft long. The missile shot out to sea and then went in a steep dive. There used to be a button on the control box for destroying the missile in the event of any mishaps, but there seemed little point with this one - as it went straight into the sea.

Moments later, there was a roar as the missile came back out and headed straight for the firing point. We all scattered, but fortunately (for us) the rocket fell back into the sea. Back to the subject of closed bolt and open bolt systems though. I think that you will find that any weapon that has a burst-fire capability will operate on the open bolt system because of the inherent danger in the closed bolt with overheating and rounds cooking off. Semi-auto weapons usually operate on the closed bolt - as they are more accurate. A bolt moving forward as you fire does not lend itself to accuracy in a single-shot weapon. I suppose there are always exceptions to this rule though!

**m3bobby** · 09-15-2010, 08:13 PM

A good exception would be the .30 Browning (Original version, not the L3) and I suppose the .5 M2.

I did some reading and the Steyr Aug LMG version fires from the open bolt, as does some version of the M16/AR15 family. I hadn't realised that the Aug uses the same Stoner locking system as the AR15 Family and the SA80 series.

Harry, do you know if the L2A1 Aussie and C2(?) Canadian heavy barrel SLR fired from an open bolt? I've only got a few BSA L1A1s and a Lithgow.

**HARRY THE MOLE** · 09-16-2010, 10:34 AM

I never gave a thought to the Browning. But when you think about it, the model 1919 is only the model 1917 without the water cooling jacket and having a heavier barrel. And the model 1917 works on a similar principle to the Maxim - which is closed bolt (lock). It is interesting to note that the Maxims (and .30 Browning) withdraw the round to be chambered on the rearward stroke of the lock. On the same stroke the empty case is withdrawn from the breech. These guns have to be cocked twice to load. The first stroke of the crank (Maxim) or handle (M1917) only positions the extractor around the base of the cartridge, it is the second stroke which withdraws the cartridge from the belt and chambers it as the lock (or bolt) returns to battery. I have to admit that I have never studied the Browning guns - even though I have all the information on their system of operation. I suppose it is just another example of a very old design soldiering on.

As for the L2A1, I have no information. But my reference book refers to the Canadian C2 as... 'The C2 is the heavy barreled selective-fire version of the Canadian semi-automatic FN rifle C1. The method of operation and field-strip of the C2 are similar to that of the C1.' I would assume though that both weapons would operate on a closed bolt, as to have two differing systems in the same body would probably be an engineers nightmare. I have an SLR, but it is the Australian L1A1 with the old-style wooden furniture. It was the only one I could find anywhere which had the same woodwork as the one I carried around in NI back in the early 70's. The forestock is of the rounded section instead of the later triangular section. Another selective fire weapon that uses the closed bolt is the Mauser C96 model 1932. There must be many more examples as well. I get far more pleasure out of studying weapons these days than I ever did firing them. It was many moons ago that I tired of punching holes in bits of paper.

Harry.

**banksy** · 05-27-2011, 01:58 PM

Very nice gun ! Great choice ! Never seen one befor though !

**GasMasksUK** · 05-27-2011, 02:29 PM

I hadnt heard of them either until chance to buy it, and just incase anyone is wondering where the natural light photos are, I'm unable to take any as my garden doesnt have any blind spots, and I have the most nosey neighbours to have ever existed and they would more than likely call the police even if i explained that they're deactivated......and I'm not joking either

Thanks

Danny

**banksy** · 05-27-2011, 02:52 PM

Lol the more I look at it the more I love it ! It kind of grows on you ! I want one ! Lol and about the next door I had keeped my collection under tabs until one neabiour received a miss delivered gun ! And they opened it ! ALS the other saw me walking past with a HUDGE shell

all took some explaining !

**lithgow** · 05-27-2011, 08:45 PM

Hello-Harry the Mole-the heavy support L2A1 auto version of the SLR fires from a closed bolt-this is because the basic FN FAL/SLR design fires from a closed bolt, a definite disadvantage as cook offs do occur with auto fire-many newer designs like the M16/AR 15 use a closed bolt for single shots and open for auto as prev stated-the mechanical action of the working parts makes single shots less accurate from open bolts, but for auto the open bolt allows cooling through the barrel as well as not having a round in a hot chamber. As to the SLR forestock the triangular wood with 2 slots is the earlier type-should have a turned wood carry handle-later rifles had the oval section wood lined with metal with plastic moulded carry handle.