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melp
July 18, 2007, 21:09
Hi!

I have an L1A1 kit, with the barrel torch-cut into four pieces and only small parts of the upper receiver. I plan on using a DSA inch pattern receiver; DSA is promising a six-month wait for it. I want to resurrect the kit to be as close as possible to an original Lithgow-made rifle, at least in form. My major problem right now is the barrel. I have acquired what I believe is an excellent metric barrel (it has left-hand muzzle threading, is not chrome lined, and has none of the traditional Australian Lithgow proof marks).

I would like to use that new barrel, which was stripped bare of any components. I know that if I want to use something like the “New Guinea” flash hidder, the barrel muzzle needs to be rethreaded. First. is it possible to get the muzzle rethreaded over the left hand threads and still have sufficient metal left to firmly attach a right hand muzzle attachment? I do not want to cut the muzzle threads off.

Second, is it possible to use the gas block off the cut barrel and correctly placed on the metric barrel? If so, how do you get the gas block off the old barrel? I have pulled the barrel/gas block alignment pin, the gas/block to tube locking pin, and the front sling attachment. From what I can tell, the gas block should come off pushing it towards what would have been the barrel muzzle. All cutting torch irregularities have been ground off the diameter of the barrel. Yet using a hammer and brass punch on the backside of the junction between the sight block and gas tube hole on the back of the gas block doesn’t budge the block from its position on the barrel. Is it rusted on? No rust is evident. Does the gas block have to be “gently” heated before administering hammer and punch blows again?

BTW, does anyone know the source of the metric barrel? It has a set of crossed banners (similar to the Australian Lithgows) with the letter P above instead of a crown. It also has a tall letter U with an smaller upper-case M within the U on one of the barrel bosses and the lower case letter x above 66 in a shield.

Thanks for your patience with questions from a newbie. :)

Abominog
July 18, 2007, 21:20
The "MU" is a South African R1/ R3 barrel.

Yes, it can be re-X-threaded.

I'd suggest you swap your metric for a correct barrel.


BTW, the F1 flash hider you have is a POS and opens up the groups. You'll want a standard L1A1 FH.

Andy the Aussie
July 18, 2007, 21:28
Originally posted by Abominog
BTW, the F1 flash hider you have is a POS and opens up the groups. You'll want a standard L1A1 FH. ....... mmmmmmm......that was not everyones experience....... ;):beer:

melp
July 18, 2007, 22:39
Andy: Thanks for the input on the New Guinea FH. I saw that Skennerton documented the poorer accuracy of that piece. I do have a standard Aussie FH, so I'll probably use that. BTW, when I took the NG FH off the front barrel piece, I noted that a new keyway had to be cut in the barrel for that FH. The original keyway (still exists in the barrel piece, nearly touching the base of the muzzle threads. The rifle had been FTR'd in 1979. Original date of L1A1 manufacture is 1964-65.

melp
July 18, 2007, 22:43
Andy: Sorry, I got you rossed with Abominog. I will note your opinion. Abominog: I haven't found any inch barrels. Can you point me in the right direction? Thanks!

Andy the Aussie
July 19, 2007, 00:03
Originally posted by melp
Andy: Sorry, I got you rossed with Abominog. .....if you meet us both together you would not make that mistake again..... ;) I have looks, charm, personality and intelligence. He got what was left.... :rofl: :rofl::beer:

It sounds as though your rifle was an original PNG sale that went through the FTR "F1ing" process.

You could always get someone to turn you a "correct" profile L1A1 barrel from a blank and utilise the gas block that came with your kit. Externally no one will know the difference and you will end up with a great shooter (if you use a quality blank).

Andy:beer: :beer:

jaykden
July 19, 2007, 01:18
PNG FH's suck. bad.



:tongue:

jaykden
July 19, 2007, 01:21
Originally posted by Andy the Aussie
..... I have looks, charm, personality and intelligence...



BWAHAHAHAHAHHAHAHAAA

ahhh, that was hilarious (as i wipe away tears). havn't had a good laugh in awhile. heh heheh heh

Abominog
July 19, 2007, 15:11
Originally posted by Andy the Aussie
....... mmmmmmm......that was not everyones experience....... ;):beer:




Ahem. And, sir, exactly how long ago was it that you fired an L1A1?

Abominog
July 19, 2007, 15:14
Originally posted by melp
Andy: Sorry, I got you rossed with Abominog. I will note your opinion. Abominog: I haven't found any inch barrels. Can you point me in the right direction? Thanks!


Marketplace on FAL Files. You could post a WTB, or wait patiently.

The best deals are the take-off barrels from old Century builds. They've been cut & re-crowned (w/o flash hider); you can get them at reasonable prices, send it out to be re-threaded, and the only difference is that yours is about 1.5" shorter than OEM (which is the goal of the PNG F1 anyway!)

Andy the Aussie
July 19, 2007, 18:22
Originally posted by Abominog
Ahem. And, sir, exactly how long ago was it that you fired an L1A1? .....bit under 12 months ago..... ;)

One of my two SLRs that I competed with was a factory built and marked L1A1F1 that shot as well or in some cases better than the other SLRs on the line at the time. The BCF barrelled rifles were the pick of he lot though.

Andy:angel: :angel:

melp
July 19, 2007, 21:30
In searching the FALFiles, I did confirm what Abominog said, that the barrel is South African (SA), and therefore metric. See http://www.saaaca.org.za/links/markings.htm

BTW, does anyone know the source of the metric barrel? It has a set of crossed banners (similar to the Australian Lithgows) with the letter P above instead of a crown. It also has a tall letter U with an smaller upper-case M within the U on one of the barrel bosses and the lower case letter x above 66 in a shield. So, that's taken care of. Now, for the other questions.

I have noted the differences of opinion on the F1 or PNG FH. I also note that Skennerton said accuracy suffered with the PNG FH. Luckily, I have both the Aussie and PNG FHs available. Abominog said I could rethread the muzzle to right handed to fit the Aussie flash hider (FH) from its present left handed 9/16"x24 TPI. A new FH keyway would have to be cut. None exists on the SA barrel. Any added comments or cautions on that?

My yet unanswered question is as follows: ...is it possible to use the gas block off the cut up inch barrel and correctly place it on the metric barrel? If so, how do you get the gas block off the old barrel? I have pulled the barrel/gas block alignment pin, the gas/block to tube locking pin, and the front sling attachment. From what I can tell, the gas block should come off pushing it towards what would have been the barrel muzzle. All cutting torch irregularities have been ground off the diameter of the barrel. Yet using a hammer and brass punch on the backside of the junction between the sight block and gas tube hole on the back of the gas block doesn’t budge the block from its position on the barrel. COLOR=blue]Is it rusted on? No rust is evident. Does the gas block have to be “gently” heated before administering hammer and punch blows again? [/COLOR] From what I've seen in the Boards here, you basically hammer the block forward off the barrel using a block of wood on the back of the GB. Any other suggestions?

Now that I know the good barrel's origin, how difficult would it be to get a Lithgow GB mounted correctly on the SA barrel? How close a fit would I get if I pressed the Lithgow GB on the SA barrel? I know that the gas hole in the SA barrel may have to be redrilled to match the GB gas hole, which is inclined about 45 degrees to the barrel axis. The SA barrel at the GB mics at 0.6923"-0.6926" diameter. What is the typical Lithgow GB barrel-bore diameter?

Again, Thank you for any added useful information. I shall continue searching the FAL files. Now that I know the good barrel's origin, how difficult would it be to get a Lithgow GB mounted correctly on the SA barrel? How close a fit would I get if I pressed the Lithgow GB on the SA barrel?

Radio
July 20, 2007, 12:41
Gas block: Yes, that will interchange. All FAL gas blocks have the same ID, all FAL barrels have the same GB OD. The only "adaptation" as you noted would be the gas port angle; no major deal.

GB Removal: No, there's nothing keeping your current GB on the destroyed barrel other than sheer stubbornness. It's a bitch to remove, but once you've "pulled the pin" that's the only restriction. (The gas tube pin has NOTHING to do with retention of the GB on the barrel, but it doesn't hurt to be thorough :wink: ) Since you are working with a barrel stub, may I suggest you use some wood or brass to protect the GB and press it off? Otherwise the traditional approach is wood/brass protection, a length of angle iron, and a BFH. Heat sometimes helps, of course. Eat some Wheaties (or spinach like PopEye does) and develop your muscles. And patience. And vocabulary of swear words.

Threading: Not only can the muzzle device threads be cross-threaded to accept either a RH or LH threaded flash hider (which is done more often than you may think), your machinist/gunsmith can also cut a keyway into your Metric barrel.

Barrel: I notice you are blowing off a lot of steam regarding barrel markings and whatnot. Respectfully, not trying to be an ass, but what the hell do you care? Unless you strip off the handguards at the drop of a hat to show everybody your proof marks, nobody's going to see and nobody's going to know and nobody's going to care. My recommendation is the same as Abominog's, get a correct Commonwealth barrel. First, it will probably already have the GB you want. Second, it will have the correct threading and keyway for your flash hider. Third, it will have the correct markings you are concerned about. Fourth, it will have the correct six-land rifling NOT found in a Metric barrel. Not that this is vitally important... but... you DID say you wanted "as close as possible to an original Lithgow-made rifle".

--Radio

melp
July 20, 2007, 20:33
GB Removal: No, there's nothing keeping your current GB on the destroyed barrel other than sheer stubbornness. It's a bitch to remove, but once you've "pulled the pin" that's the only restriction. (The gas tube pin has NOTHING to do with retention of the GB on the barrel, but it doesn't hurt to be thorough ) Since you are working with a barrel stub, may I suggest you use some wood or brass to protect the GB and press it off? Otherwise the traditional approach is wood/brass protection, a length of angle iron, and a BFH. Heat sometimes helps, of course. Eat some Wheaties (or spinach like PopEye does) and develop your muscles. And patience. And vocabulary of swear words.

Radio: Thanks for the answers. I guess I haven't eaten my share of Wheaties (but I have had spinach) for a while :o . I used a piece of 1/4" aluminum sheet at the back of the GB, between the gas tube and barrel, and wood block on the floor for the forward part of the stub. After application of propane torch and a 2 pound hammer over a 30 minute interval, I managed to get the GB moved forward about 1/8", and it's still holding onto the barrel. Unfortunately, the administering of the beating led to the handguard screw hole in the GB becoming a bit ellipsoidal:sad:, so I'm bagging it for tonight. I guess I should have put solid partial pins in the outside part of the screwhole to prevent that damage. I wonder if that irreperable, or can I just pass a drill through that hole to allow the screw to pass through:confused: ? I really must have a stubborn GB. I'm going to have to find a shop in this area that has a press.

Again, Thanks for the info to all that responded. Any additional comments would be appreciated.

Melp

NHBandit
July 21, 2007, 11:16
Originally posted by melp
Unfortunately, the administering of the beating led to the handguard screw hole in the GB becoming a bit ellipsoidal:sad:, so I'm bagging it for tonight. I guess I should have put solid partial pins in the outside part of the screwhole to prevent that damage. I wonder if that irreperable, or can I just pass a drill through that hole to allow the screw to pass through:confused: ? I really must have a stubborn GB. I'm going to have to find a shop in this area that has a press. [/COLOR]

Again, Thanks for the info to all that responded. Any additional comments would be appreciated.

Melp Step 1... contact James at http://www.gunpartsguy.com/ and buy a new gasblock. While you're there get some inch pattern flash hider indexing washers. Choose the right combination of washers to allow the FH to be tightened onto the barrel & index properly and don't spend money on having the cut made in the barrel for the indexing washer. Instead grind a flat on the bottom of the washer so it fits the slot in the FH and install it so it looks like it's actually serving a purpose. Metric flash hiders don't use an indexing washer and I've never seen one come loose that was properly torqued on. Option 2.. as others have said post a WTB in the marketplace and find a good inch pattern barrel. Save all the parts you've managed to FUBAR like the gasblock and when you have enough weld them all together into a cool sculpture. If you bleed take pictures. You'll need them later when you apply for WECSOG points. :beer: