L39 & L42 Barrels - An open offer to forum members

[newcastle]

That may be true but sadly the man at the top is very much a stooge of the UN and thus we wait for korean garands and 7.62 barrels in vain.

[Peter Laidler]

Regarding the remaining tolerances and material...... Maybe Ensci can give us the exact material spec that I couldn't get when I was writing about it. But it was certainly a good quality material and cut like a dream. As for the breech thread spec, then without any doubt, this will be a bog standard BSI (British Standard) 1" 12 (or is it 14?) TPI whitworth 55 degree form to the same BSI tolerances. I'll gauge a few barrels up to get a ball park chamber depth with a 1.635 CHS gauge.

The machinist/barrel maker could experiment a bit by 7.62mm chambering a few scrap No4 barrels. (He only needs to chamber ream as far as the 7.62mm neck and there's sufficient meat in a .303" chamber to form a 7.62mm neck sufficient to make a few depth calculations.......).

The muzzle crown is what it is. The foresight block band is a different matter. The early ones that were not accepted for service use had the bog standard No4 foresight block band but the service standard had a larger diameter, But this varied wildly ( I mean wildly in engineering terms.......) The bored out L42 block band wasn't available as a spare part because of this. If you needed to replace it, the rifle was sentenced to a Field Workshop and an existing No4 block band was machined to suit and re-sweated on

To be honest, with a barrel blank of sufficient length and diameter and a decent set of drawings, anyone half decent turner with a decent lathe could turn one up - or down - in a few hours

[bouletbill]

Much of Europe and also (I believe) Australia, have lived with anti military calibre regulations for many years. One of the cheaper solutions is to modify the chambering a small amount and call it something else (re-proofing of course), using same bullets and almost identical performance i.e; 7.7x54 instead of .303". This may not satisfy the purist collector but these dumb regulations could breath some fresh life into a variety of old wildcats.

[Brian Dick]

The BATF&E banned all imports of surplus military barrels to the USA in July 2005. It is being litigated but with the current political climate, chances are slim to none that things will change. The interesting part is that identical barrels manufactured overseas for commercial sale can be imported.

---------- Post added at 07:49 PM ---------- Previous post was at 07:40 PM ----------

I forgot to mention that Alan de Enfield is exactly right about the State Department denying approval of export licenses for firearms and barrels in caliber 5.56, 7.62 and .50 M2 destined for end users other than the police or military.

[Bruce_in_Oz]

Standard No4 barrel data:

Thread is 1.001" x 14TPI Whitworth (55deg.) form. (NOTE SMLE and Martini thread is 49deg. 40min included angle, NOT 55 and DEFINITELY NOT 60deg.)
Crests flattened to min 0.996" dia.
Pitch dia. 0.9553"; 0.9523" min.
Max allowable eccentricity of thread to bore: 0.004" (radial) or, 0.008" "clock" (diameter) reading.

VERY IMPORTANT:
Headspace on the L-42 is different!!

As per page 111 of the excellent book on the No4 T and variants, by some chap called Laidler (and Skennerton):

GO gauge is 1.628"
NO GO gauge is 1.635"

These are different from the sort of gauges that you whack into an L1A1 or M-14, let alone .308" Win gauges.

From p.110 of said tome: The material is EN 19AT steel.

[bigduke6]

BSI (British Standard) 1" 12 (or is it 14?)

Must be a sign of the Alzheimer's setting in ? 14 TPI ,

To be honest, with a barrel blank of sufficient length and diameter and a decent set of drawings, anyone half decent turner with a decent lathe could turn one up - or down - in a few hours

The important thing is a Taper turning attachment, one of these and your in business, but to be honest, most barrel blank suppliers will contour any blank for little cost and I know Lothar Walther charge approx $65, 41 pounds (pound sign not working on laptop) for the ammount of time setting everthing up, and your own time on the machine etc, more cost effective to let them do the contour including the Tenion, the finish is excellent, so you will have a blank with correct contour and a machined tenion ready for the thread and chamber.

Most expensive part is the Chamber, If you buy your own reamer easy enough to do, Think in the USA you can rent them? that leaves the thread, no need to worry about the thread start, just machine thread and add knox form on completion of the final CHS.

One cheaper way of doing it, is to look out for any old target rifles based on the No4 action, plenty still about with hammer forged barrels, still may need to make a spacer etc for correct CHS and still need a reamer.

[Surpmil]

The BATF&E banned all imports of surplus military barrels to the USA in July 2005. It is being litigated but with the current political climate, chances are slim to none that things will change. The interesting part is that identical barrels manufactured overseas for commercial sale can be imported.

---------- Post added at 07:49 PM ---------- Previous post was at 07:40 PM ----------

I forgot to mention that Alan de Enfield is exactly right about the State Department denying approval of export licenses for firearms and barrels in caliber 5.56, 7.62 and .50 M2 destined for end users other than the police or military.

That's interesting Brian. So that L42 you were posting about exporting earlier this year(?) and how it remained in some sense the liability of the previous owner/exporter even after the buyer in Canada (?) got it; that would no longer be exportable now?

There were plenty of hammer-forged Enfield barrels sold direct to the civilian market, why would these be banned? I have one here that has no markings, not even UK proofs, except "CR1470 D69* SRM2" (*Enfield "D") Why should a barrel like this be blocked from import to the US?

[Peter Laidler]

Sorry about the duff gen re the TPI Big Duke and others. It's caused by thinking on your feet and remembering your 6th form science lessons where Mr Percy always told us that in order to save brain space, to never deliberately remember anything you could easily look up in reference book. Good job we have Machinerys handbooks!

On a similar subject to the thread, my pal and I machined a 7.62mm L4 Bren barrel down to fit his No5 rifle. While we didn't have to ream a chamber, we still faced the CHS problem so we took the breeching up shoulder against the breech face against the breech end and calculated everything mathematically - and it worked. Like Big Duke suggested, we cut the extractor slot approximately but had to finally hand correct it by a tad to get it correct. The breeching up flat was also out of true but what the hell! It still breeched up, he's still got it and is still shooting it! After it had been through the workshop system it looked like new.

Regarding the UN and their embargo's...... In Bosnia my friend Maj Alistair XXXX thought that UN stood for Useless fxxxxxg Numpties

[Brian Dick]

Hi Surpmil,

You're exactly correct. Even the L39A1 is banned from export. The State Dept. caliber policy was put in effect in November 2009 if I remember correctly. I managed a couple to a collector in Canada a year ago and was lucky to get them approved. The Chief of the DDTC made the exception but then told me not to ask again. It's only because the buyer and myself are well known to him that he allowed them to go.

There are supporting documents required. I must have an invoice from the manufacturer to prove that it's new and for commercial use/resale. Many think that the examiners and Chiefs are stupid and ignorant or both. It's simply not the case. I have great respect for the Chief of DDTC, US Dept. of State and many of the examiners. I also have respect for many of the examiners at BATFE Imports Branch. They are doing a job, treat me with respect and I've actually forged a good working relationship with them over many years. Most are retired or former military and some are enthusiasts themselves. I've helped them out a bit in the past. I've been involved in the hopeful retransfer of the M1 Rifles and Carbines from Korea, (it's not over yet), and they help me as much as they can in return.

Brian

---------- Post added at 11:11 AM ---------- Previous post was at 11:07 AM ----------

Hey Peter, the sun's out! I'll be in the workshop shortly!!

[jmoore]

The important thing is a Taper turning attachment, one of these and your in business, but to be honest, most barrel blank suppliers will contour any blank for little cost and I know Lothar Walther charge approx $65, 41 pounds (pound sign not working on laptop) for the ammount of time setting everthing up, and your own time on the machine etc, more cost effective to let them do the contour including the Tenion, the finish is excellent, so you will have a blank with correct contour and a machined tenion ready for the thread and chamber.

Talked "ftf" with a Lothar Walther man today (purely by chance). He indicated that doing a barrel complete with the hammer forged "scale" finish would likely be very cost prohibitive for a short run, as the set up is far more involved than doing a net near shape with a finish turn. Oh, well...