An Odd Characteristic of the SMLE

[Thunderbox]

The only known example of a SMLE Sniper having a point of impact that would coincide at 300 yards and then open out beyond that is with the Great War Sniping Weapons with the scope offset to the right. The point of zero of the WWI sniper weapons was set at 300 yards, ...

Is that actually noted in a drill book somewhere, or is that from accumulated sniper lore?

I ask, because my PPCo (admittedly of completely unverifiable provenance) has the scope parallel to the bore in the horizontal axis (or is that the vertical axis?!); hence the POI remains offset to the left by a fixed amount at all ranges. Given that the offset is only about 1 1/2", it would seem pointless trying to have a "converged zero" at a specific range plus correction factors for every other range - far easier simply to aim 1 1/2" to the right, whatever the range.


Getting back to the OP's anecdote, the answers must surely be; (1) no, No1s do not typically exhibit lateral spread; (2) any lateral spread reported by the sniper is most likely down to a fault in scope/ mount/ shooter on that particular rifle....

[Beerhunter]

The rear locking of the Lee-Enfield action is well known to "compensate" at longer ranges but up and down NOT laterally. Maybe the old boy was heard incorrectly or had got confused.

[Roger Payne]

I'm inclined to agree with Thunderbox. Simon, is there any chance (at your convenience of course) you might dig out this literature re all offset SMLE scoped snipers, as I'd have thought it more logical & consistent to mount the scope parallel to the bore so the amount the sniper had to aim off was constant? I have been getting repro's of many of these mounts made now for over ten years, & whilst I have no control over who has subsequently fitted them to rifles I know that several eminent gunsmiths known to these pages have done so. I would be interested to know if they were machined up to sit parallel or convergent.

Oh, & the scopes weren't offset to the right - it was to the left....I presume you'd had one over the eight when you typed that!

ATB

[Peter Laidler]

The old chestnut about No1's 'compensating' for, well, whatever it was, nobody really seems to have identified it was regularly aired during class discussions and especially later at academic level. As pointed out earlier and repeated by Patrick, once the bullet has left the bore, it has no memoiry so quite how it comensates is anyones guess.

Like T/box,I eagerly await any printed matter about offset telescopes or even open sights being zeroed without the offset being taken into account.

[Bruce_in_Oz]

I was always intrigued by full-bore shooters who used a SMLE or No4 for some distances and a P-14 for others: similar length barrels, generally the SAME sighting units.

I heard various stories about different rifles shooting "better groups" at oddly divergent ranges.

As Peter noted, once the bullet has left the muzzle, the barrel has NO more effect on it. (Irregular muzzle-blast dispersion aside). So, given that EVERYBODY was using the same, bog-standard Mk7 ammo, what, if anything, could be happening? (Apart from 20th Century Voodoo)

The waves that are generated in a barrel from the moment the trigger is pulled to the point of departure are immensely complex. The wave patterns are multi-mode: vertical, horizontal, axial and torsional; all at the same time. It is variations in these, from shot to shot, that cause the most grief after the ultimate insult of a dodgy crown. This is why proper bedding is supposed to produce CONSISTENCY in the wave patterns from shot to shot as it CANNOT eliminate them. If the muzzle is pointing up a squillionth of a degree EVERY time a bullet departs, that is consistency and you just go with it. What you end up with is a set of behaviours that suit your ammo. That is why, every time you fiddle with your ammo, either by changing brands of factory fodder or the balance of components in "home-brew" that you end up back at the range to re-zero.

Mk3* SMLEs and No4s were build around Mk7 ammo, end of story. (Lets just gloss over the odd allowance for Mk 6 ammo in the throating of SMLEs for a minute). If you "free-float" a No4, it MIGHT shoot with a handload that you come up with eventually, but it is almost impossible that it will both group the same AND to the same point of impact with said Mk7 ball. If you wind a Lithgow heavy barrel into your SMLE action, it will NOT perform the same as the original barrel. After you have cheerfully removed a lot of wood and deleted sundry bedding gizmos that were used on the standard barrel, one could hardly expect it to. It may be better; it may be not. Most of any improvement will possibly come from the simple fact that said heavy barrel is (hopefully) NEW and has not yet had its throat burned out by cordite or its crown blasted away. As for the interesting practice of opening out the muzzle hole in the nosecap with a hand-held rat-tail file and bashing in a bit of rubber hose as a "bearing"...........

Back in the days before Oz lost its sense of humour about such things, I worked on a lot of M-14 / M1A rifles. One regular job was to give them the AMTU match rifle treatment (minus the NM barrel, of course). This worked well in MOST cases. However, the improved groups were generally NOT terribly close to the original MPI. Re-zero and carry on! One chap insisted on having his “free floated”, i.e., there was no “pull-down’ of the barrel by the cap behind the gas cylinder. This rifle shot F4 and M80 ball all over the place; but with hot-loaded 125gn Speers, it was a screamer.

[Simon]

[QUOTEOh, & the scopes weren't offset to the right - it was to the left....I presume you'd had one over the eight when you typed that![/QUOTE]

Doh "Stupid Boy Pike"

Roger,

I'm not saying that mounting system was machined to collimate at 300 yards, far from it. There is only one way the mounting systems can be installed and that is by carefully machining / installing them to be parallel to the bore of the weapon.

What I am saying is that I have read somewhere, unless I'm losing my bloody marbles, that the pointer of the grat was zeroed to coincide with the point of aim at 300 yards. I'm not disputing the point that if the scope is offset 1 1/5" to the left of the bore then all that Tommy Atkins has to do is simply aim off by the same amount at any given distance. Lets step back a minute and way a few things up, the weapon / scope combo's where set up by PP Co, Whitehead Bros, Wm Evans, Holland & Holland, Purdey, Watts, Bartle, Atkin etc etc. So each manufacturers mounting system would be offset to a different degree and machining and installation tolerances would also result in a difference in offset, can you see where I'm going with this?

Tommy Atkins is issued with his, for arguments sake PP Co / PP Co SMLE, who tells him what the offset of his scope is? Lets assume, again for arguments sake, that he's at the Sniping School and the Sergeant Armourer informs him of his offset and he proceeds to zero the weapon on a KD range. At what range does he zero the weapon? Yes it does matter because because if he sets up at 100 yards and is only 1/8" out the weapon would be 1/2" out at 200 and so on and so on. And that would be setting up the weapon under nice controlled conditions where no bugger is likely to be shooting back at you.

The next step is that Tommy is off into the front line to "have a bash at Fritz". He spots said "Fritz" about 250 yards away and takes aim, as he's been taught, 1 1/2" to the right of said German Bonce and lo and behold misses because the small error in zeroing is exagerated as the distance to target increases. Lets be honest here too, you've got a 2 1/4x scope with a grat that as good as obscures the target and we're expecting Tommy to somehow manage to aim 1 1/2" inches off? God forbid he ever has to adjust deflection in or near the front line when the aiming point might be a distant tin can or some or piece of Battlefield debris.

So lets examine the point of impact zero at 300 yards theory. Under the controlled conditions of the Sniping School he sets his POI and off he pops to the front line. Now we pick up the same scenario as above except we know that the weapon is on at 300, there's no need for him to even remotely consider aiming off. He places the pointer on the bridge of the nose of his intended victim and pulls the trigger, result? A hit. Albeit 1/2" to the right of his point of aim. Should the need arise to adjust the telescope he doesn't have to make sure his hits are consistently 1 1/2" to the left of his point of aim he merely picks his tin can and tries to hit the bloody thing, no mean feat in itself when the target is likely obscured by the Grat pointer anyway.

I can see the logic in both theories but be honest with yourself, ignoring the fact that the offset scope idea is ridiculous anyway, which zero set up would find the simplest to maintain?

Cheers,

Simon.

P.S. Its worth keeping in mind that the vast majority of the trench lines were anything from 50 to 350 yards apart.

P.P.S. Yes it sounds ludicrous to zero for offset scopes etc but the thinking of the time wasn't exactly enlightened was it? Mass Human wave assaults, using shrapnel shells to cut barbed wire, one last big push and we'll send in the cavalry, offsetting the scope in the first place so you can clip load the weapon, and lets not forget that as late as 1915 a considerable number of the officer class still considered Sniping to unsporting. The list goes on and on

[Roger Payne]

Simon,
Thanks for clarifying. I get your drift, & in fact your point is probably another variation of what was done in practice. However, I am going by what it says in pam SS 195 Scouting & Patrolling (December 1917), page 50, viz:

'Offset - With the telescopic sight fitted to the left side of the rifle, it is necessary to allow for ''offset'' when zeroing deflection. The sight should be adjusted so that at 100yds range the shots strike one & a half inches to the right of the point of aim. A rifle so zeroed may be taken as shooting straight for all sniping ranges. Only when shooting at a small mark, such as a loophole at 100yds should this one & a half inches be allowed in aiming.'

After reading the various postings I thought I might have seen something on the matter in SS195 at some point in the dim & distant past, so I dug it out.
I may be interpreting it wrongly but it suggests to me that the pointer on the scope is zeroed to be pretty much parallel to the line of the bore - I know there were various scope & mount manufacturers, but one & a half inches is probably a reasonable approximation to the average offset of most scope/rifle combo's; & it is the also the amount of offset at 100yds. Having said that, I would agree there is clearly a degree of compromise implicit in these instructions, which have to be applied to a variety of scopes & scope mounting systems.

My brain's starting to hurt now....

ATB

[newcastle]

Correct me if I'm wrong. but a scope offset by 1 1/2 inches to teh left, and zero'ed at 300 yards, would hit 1 1/2 inches to teh left at 600 yards assuming the bullet didn't swerve due to rotation a la shane warne. Given the date I woudl think this would be an acceptable compromise for the sniper, though probably not the CORRECT way of doing things.

[Beerhunter]

The old chestnut about No1's 'compensating' for, well, whatever it was, nobody really seems to have identified it was regularly aired during class discussions and especially later at academic level. As pointed out earlier and repeated by Patrick, once the bullet has left the bore, it has no memoiry so quite how it comensates is anyones guess.

Not an old chestnut at all Peter. It may not have been discussed in class but it was regularly discussed in Guns Review in the days before purpose-built 7.62mm rifles like the Swing.

The result, based on the experience of the contributors was: was P14s for Century and No.4s for Stickledown.

As to the the bullet having no memory, are you sure? That memory being based on what the barrel/action was doing during it journey up it and just as it left it. For example the rifling in a barrel causes a bullet to spin during the whole course of its subsequent journey.

[Peter Laidler]

Er........... No Simon, the amount of offset (within the bounds of reason of course) between each manufacturer is pretty well academic to the sniper, as is the distance between trenches and anything else. The only thing he's concerned with is distance. There is no earthly logic in the zeroing at 300 yards theory........ it is doomed to failure at any other distance, near or far. Better to zero in exactly as taught, by the book as detailed by DRP in thread 27 and be sure that you'd hit the man at any (?) distance, albeit 1.5" to the right.

After reading 'the book.....' in thread 27, I cannot imagine for the life of me, some budding sniper telling the sniping school staff that he's had a brainwave and he's got a theory that it'd be better to zero his rifle at... and.......... Nope, it wouldn't work. Like I said. Better to hit 1.5" off or slap bang on if you aim off a tad than miss totally for want of remembering some mathematical formula. To be honest, some of them couldn't even remember the range scale clicks up the scale, knowing that it would be one of the end of course exam questions!