LM6 dust cover & barrel thread

**Bushie** · 05-05-2013, 18:16

Do any of you guys know where I can get a dust cover for my LM6 or even better a dust cover that has a picatiny rail on it. Another question, do any of you guys know what thread is cut on a LM6 barrel where the flash hider screws on, is it a 13/1 by any chance? I hope there are some fundis on this site that can help me, Thanks.

**A-R** · 05-05-2013, 21:47

The barrel thread is M13 x 1.

If you want to fit an optical sight, consider the other options as well. The dustcover is really too flimsy to retain zero with a scope attached. The one we used in the army, with "MNV" attached, was heavily reinforced, with grub screws to tension it. Even so, we never carried the rifle with scope attached. It was only mounted, once in position (at OP or whatever).

Even with only the peep sights, the dust cover moves. I always bent mine slightly, to tension it. That way it returns to the same position after every bump.

My LM is equipped with a rail from RHT. The FAB defence and UTG systems also look sturdy. They might be pricey, but worth it.

**ady** · 05-05-2013, 21:55

I agree with what A-R says. I have gone the FAB Defence route from RHT and can highly recommend it. I also have a side mount for a scope that the bisley shooters used in defence force shoots with a Lynx M4x20 scope.

The FAB Defence pistol grip is also very nice.

http://www.rhtechnologies.co.za/pFAB...nse-AG-47.aspx

http://www.rhtechnologies.co.za/pFAB...nse-PRG-L.aspx

**JS4** · 05-05-2013, 22:35

Speak to Paul at TacSHAC.

**Bushie** · 06-05-2013, 08:50

Thanks for the advice.

**Dick** · 22-05-2013, 23:11

I assume you mean 13 x 1 metric. No such thread exists as far as I know. 14 x 1 is standard metric fine, not sure about 12 x 1. It could be the half inch x 20TPI that is common for suppressors. If you have exposed the thread it is easy to measure.

**A-R** · 23-05-2013, 10:07

Originally Posted by Dick

I assume you mean 13 x 1 metric. No such thread exists as far as I know. 14 x 1 is standard metric fine, not sure about 12 x 1. It could be the half inch x 20TPI that is common for suppressors. If you have exposed the thread it is easy to measure.

Sorry to burst your bubble. 13mm x 1(pitch) does actually exist. I know you won't buy a tap for it at your local hardware, but that is what the treads on all LM/R 4/5/6 muzzles are.

Just for interest's sake, the older FN-FAL's, with slotted flash hider, have a standard M14 x 1 thread. The later models (R1 and lookalike) have Left Hand tread.

1/2"-20TPI is indeed the standard for most .22 rimfire rifles. There are some exeptions, like a S&W 15-22 for example. They use 28TPI iirc.

**Dick** · 26-05-2013, 22:56

[QUOTE=A-R;440311]Sorry to burst your bubble. 13mm x 1(pitch) does actually exist. QUOTE]

Doesn't burst my bubble at all - I'm very interest to learn that. I've cut enough threads by tap, die and lathe to know them fairly intimately, and I'm surprised that 13 x 1 exists. But if you can see the thread, it must surely be easy to measure ?

**atunguyd** · 27-05-2013, 00:01

yep the LM is 13x1. In reality there is no such thing as a thread that does not exist just one that is not standard or even defined. just look at the threads that are used in things like telescopes. you can cut just about any thread on a lathe as long as you can swing the stock.

I recently ran into the LM thread while making a part to fit onto the barrel. I was also thrown off by the measurement of 13x1. I couldn't even find it in my copy of the machinery handbook.