No1 Mk3 up pressures?

[RJW NZ]

Am I correct in thinking that the barrel up pressure on a No1 mk3 is established entirely by the stud and spring under the nosecap, and that no bedding at the barrel tip is involved as on the No4?
thanks

Information

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[Thunderbox]

Yes, it seems that the barrel was intended lie along the barrel channel everywhere except the portion between the chamber shoulder and 1/2" before the inner band. The tension or spring in the barrel caused by the inner band at one end and the stud/nosecap at the other is quite mild compared to the forend bedding of a No4. On a No1 the band, stud and nosecap seem to be designed to re-centre the barrel after movement during firing.

[Bruce_in_Oz]

The trick seems to be "multi-point" bedding.

There is the inner band, which acts as a sort-of damper with some downward pressure aplied as well.

There is the spring-loaded stud under the nose cap which applies considerable upward pressure.

And finally there is the barrel hole in the front of the nose cap. This one is interesting, as the hole is not just a a simple round job, but has an additional section cut away at the top of the barrel hole. The muzzle end of the barrel is supposed to bear against the two small points where the main hole is relieved by the secondary cut. The upward pressure to do this is provided by the spring and plunger hidden under the rear of the nose cap.

All of this was done to "regulate" the barrel to the service ammo specified. Has anyone got more data on the bedding and "loading" of a Mk1 SMLE barrel? The key is the difference in barrel vibration patterns of the Mk6 (round-nosed, "medium velocity" bullet and the Mk7 "high velocity" job.

The "range boys" did all manner of “interesting” things to the bedding of SMLEs in order to persuade them to shoot better groups at longer ranges and with the standard issued Mk7 ball ammo. I suspect a great deal of the "results" were, in part, psychological.

My very first No1 Mk111*, circa 1971, ($5 Aust.), and whilst still at school, was a Lithgow that had been "rangified" by the installation of a heavy barrel and a couple of other mods. One of these was that the barrel hole in the nose cap had been enlarged with a coarse rat-tail file, and it seemed to be less than round and concentric. The muzzle was now “supported” in the modified nose cap by a small section of rubber hose. The barrel channel in the fore end and hand guard had been “enlarged” to clear the barrel.

I wanted to have it in “original” configuration so, by way of “restoration” it was fitted with a “proper” sight on a suitably reamed bed and the rubber-hose “muzzle bearing” was replaced with a squeeze of black-coloured silicon rubber.
How did it shoot? Probably better than me. I used it for years both for hunting and target shooting. Then, quite some years later, I went mad and sold it to pay for a nice No4. Good shooter though it was, it just did not quite have the same “vibe”. (Boom, Tish).

Dropping in one of the Lithgow heavy barrels would have the effect of resetting the game. Note that the Australian SMLE sniper rifles do not use the inner band and the hole in the fore-end is plugged. Thus, the rifle was re-regulated for same old ammo but with a different barrel.

[RJW NZ]

Really interesting thanks, Bruce and others. I'm doing this research to expand my knowledge base as I complete my book on enfield accurizing techniques for home handy shooters (coming soon, fully illustrated etc etc). I took my Lithgow down yesterday and found considerable up pressure exerted by the wood, so at least in this case the spring is making extra pressure.

Any ideas if the enfield No1, the model with the sight ears turned in over the front sight circa 1905, has the same nose cap set up as the mk3 with the spring and stud? The No1 I have here has an EFD repro fore end and an H barrel, so the fore end is drilled for a stud but I've got no indication what would have been used with a stock barrel, stud yes or no in 1905?

[Son]

The foreend should take between four and seven pounds of pull to get it away from the barrel at the muzzle, without the trigger guard fitted, the inner band done up or the barrel centering stud fitted.

Both the inner band and the barrel centering stud were add-ons to help "average out" the bedding so that a slightly warped foreend wouldn't cause the rifle to fail the accuracy test, therefore needing to be sent back and re-worked by armourers.

Both locations were found to be neutral nodal points on heavy barrels, that's why the inner band and centering stud were omitted from H rifles.

]This pic shows very clearly the contact areas. The rifle is a '55 FTR and was unfired from proof at the time of stripping.

[Patrick Chadwick]

This multi-point business has irritated me with my No1 MkV. Has anyone else tried firing their No. 1 with a "blank" barrel - i.e. no nosecap, springs etc? And if so, how was the grouping (the POI was probably shifted a long way)?

[Thunderbox]

The foreend should take between four and seven pounds of pull to get it away from the barrel at the muzzle, without the trigger guard fitted, the inner band done up or the barrel centering stud fitted.

Are you sure about that, or have you seen this written in an EMER somewhere? I ask, because all of the completely original rifles I have ever examined have the barrel lying flat along the barrel channel with only a very slight down pressure at the muzzle (inner band unscrewed and nosecap removed to release stud). Since those particular rifle were presumably "built to specification" at the factory, I've always taken them as a template.

[jmoore]

Both locations were found to be neutral nodal points on heavy barrels, that's why the inner band...

I noticed that the inner band on early SMLEs is centered under the outer band- was it moved when the Mk.VII ammo was adopted, or was it to strengthen the handguard and fore stock?

[5thBatt]

I noticed that the inner band on early SMLEs is centered under the outer band- was it moved when the Mk.VII ammo was adopted, or was it to strengthen the handguard and fore stock?

The band was moved with the introduction of the MkIII in 1907, MkVII ammo was 1910.
The early Mk1 SMLEs didn't have the stud & spring under the nosecap & when introduced had a longer spring which was changed iirc during MkIII production to a shorter spring.

[Son]

Are you sure about that, or have you seen this written in an EMER somewhere? I ask, because all of the completely original rifles I have ever examined have the barrel lying flat along the barrel channel with only a very slight down pressure at the muzzle (inner band unscrewed and nosecap removed to release stud). Since those particular rifle were presumably "built to specification" at the factory, I've always taken them as a template.

The key would be... how long ago were they built to specification at the factory, and what sort of treatment have they endured since in the way of use and environmental. I would suggest that if they still passed accuracy testing, they were good examples of the inner band and barrel stud doing their job as the original bedding "faded". Four pounds isn't much to start with. But over the years the foreend probably eased under that weight, reducing it further.

Still looking for more references- first one is from the LES, P164, in an extract taken from armourers instructions. The paragraph is titled "Fitting a new foreend" and part (c) reads....... "....Assemble the foreend. Replace the trigger guard and screw. Test for springing and adjust the foreend as necessary."

Ok, from this, what I wrote above is incorrect in that the test is conducted with the trigger guard fitted....

Next reference from "The Armourers Handbook", Gale and Polden Limited, Page 13 "Barrel Bearings"
1) There must be hard bearing at the draw, which transmits the shock to the stock.
2) A distance of one inch back from the front end of the body.
3) The reinforce or bearing of the barrel.
4) The inner band, half an inch either side.
5) There should be a light bearing from the inner band to the top when fitting.

I'm reading 5) "light bearing" to say it's a bit more than just touching... once again, four pounds at the end of the foreend isn't a hell of a lot. Same weight as a medium trigger setting. Having messed with more than a few range bedded rifles, the trick is to make them shoot from cold through to max required operating temp (which would be governed by the required rate of fire for the practice) without the POI moving as they heat up.

The inner band issue, Mk1 vs MkIII. The band was moved so the handguard could be made stronger. It too is noted somewhere... I'll keep an eye open for it as I go...

More to follow eventually...