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Just curious, in as much as the MKVII cartridges velocity is approx 2500 fps and considerable more then the 2000 fps the Long Lee Enfield was designed for. What impact would a MKVII rd have on the point of aim of a Long Lee Enfield that was sighed in at 100 yrds with the older rd?. Would the MKVII shoot higher or lower and would it change windage like shooting more left or right of center because of the faster bullet? Ray
rayg, When the Mk.VII was in the process of selection there was also found that the forcing cone needed to be modified slightly to improve accuracy.
I have no idea how badly it'll shoot, maybe there'll be no difference, but I'd expect some accuracy degradation. Let us know.
Brad
What's a forcing cone? Oh, OK, I looked it up. Never mind.
Hi Brad, not so interested in accuracy but the difference in bullet impact between the two cartridges. As I understand, a slower heavier bullet would impact higher at 100 yrds then a lighter faster bullet. So a MKVII bullet would shoot/strike lower then a rifle sighted in at 100 yrds with the older heavier bullet. Now what about windage. The Enfields have a right hand rifling twist. Would a faster bullet effect bullet impact/strike more left or more right then the slower heavier bullet, or would there be no change? Ray.
Ray, In that context, a very interesting question regarding the windage aspect. I can't wait for the ballistic guru's responses.
Brad
Enfields have a left hand twist. Higher velocity ammo from my experience will hit higher.Quote:
Originally Posted by rayg
Oops you're right Fred, got it mixed up, Ray
:D Well, I got something right today!
Ok, I shot my unmodified 1896 Long Lee MkI with MKVII ammo and the bullet impact was low and about 3-4" to the right. The other day I had shot my other Long Lee with the same ammo and the impact was point of aim center.
I looked at the front sights and noticed that on the one that shot center, the blade was centered in the sight and the blade on the un-modified rifle was offset to the left and not in the center. There was a star type stamp on the side of the sight of the one with the centered blade indicating a modification. So apparently the front blades were moved to compenstate for bullet drift between the older rd and the MKVII rd.
Which must mean there is a difference in windage impact between the two cartridges. Ray
Ray, it was a case of when the Metford barrels were replaced with Enfield barrels, and the newer rifles came out with Enfield rifling, the soldiers noticed that the rifles were shooting to the left. These sighting problems were encountered during the Boer War. This was remedied per LoC (list of changes) paragrahs 10393, 10439 & 10798 by fitting removeable foresights, pinned to the block and altering the "V" notch in rearsight leaves and slides. The rifle Without the star on the front sight base has the front sight Base set .02" off to the Left of the center line of the barrel and the barley corn front sight blade set .05" to the left of the center of the barrel. The rear sight slide notch is cut .03" to the left of the center of the barrel. as is the rear sight battle sight notch at the top of the rear sight leaf, also set .03" to the left of center line. The rifle that has the barley corn front sight blade, is it a MkI* that was made without provision for a clearing rod? The star on the right of the front sight block or base indicates that the rifle's barley corn sight is set only .02" to the left of center. Since the front sight base, like on the other rifle is also set off .02" from the center of the barrel, the barleycorn blade is actually centered on the base. That rifle has a * punched on the right side of the base. This difference in the position of the two front sights I believe was caused by a difference in the ammo which brought the front sight .03" closer to the right again. How the rifles shoot with Mk VII ammo is anybody's guess since they weren't designed to shoot it. If your rifle is shooting dead center of aim, you're fortunate. My CLLE's have adjustable rear sights that were put on them to remedy this very problem and get them to shoot dead on with whatever ammo they were using. Fred
Thanks Fred, interesting. My rifle with the * on the sight shoots dead center with the MKVII ammo. It has no provsion for the cleaning rod so it was upgraded. My other all matching one with the blade offset to the left, shoots 3-4" right of center. It looks like if that blade was moved to the center like the one with the star, it would shoot more center also with the MKVII ammo. That sight has no * so I'm assuming it was not modified and was still sighted in for the heavier slower bullet? Ray
Ray, what is the year of manufacture of the Mk I* rifle whose front sight has the * ? If it has no provision for the rod and has a solid stock and was made after May of 1899, then it has no upgrades. It was made like it is at the armory. The rifle was suitable for the ammo that they were using at the time of the rifle's manufacture. The other rifle was never upgraded and was probably not used with the later ammo. I wonder if my Mk I* would shoot accurately with Mk VII ammo too? It being made in 1900 was also made without any provision for a rod and the sights are accordingly suited for the later ammo. The star on its front sight base is not an * but is actually a six pointed star.
https://www.milsurps.com/images/impo...ronsight-1.jpg
Fred, the rifle with the starred sight is dated 1896 but has been upgraded. If the front blade on your rifle is centered, it probably should shoot center.
Apparently the blades on the front sights were originally offset to the left to compensate/allow for bullet drift to the left. I assume that's why the blade on my un-modified on is set to the left which in turn makes you shoot more right at close distance but the bullet would drift closer to center at a further distance.
I wonder at what distance would the bullet shoot center if the rifle is shooting 3-4" right at 100 yrd, Ray
I seem to remember (a long time ago) that there was a discussion on another forum about long distance shooting and the correolis effect.
This being that once the bullet has left the rifle it is in free-space but the Earth continues to rotate, at distances around 1000 yards the target is 'nowhere' near where it was.
This applies if Shooting Due North or Due South.
If shooting Northwards the bullet will impact to the East and if shooting Soutwards the bullet impacts to the West.
The correolis effect is calculated as
Y = 2wVsin (latitude)
W = Earths rotaion (0.0000729 degrees per second)
V = Bullet speed
Example at 45 degrees North and a bullet speed of 2800 fps the equation gives 0.3fp second per second
At 350 yards you'll get about 1/2" displacement
As a rough guide for longer distances use 1" correction for each second of flight time.
Throw in the wind effect over 1000 yards and it becomes a tad more tricky to calculate.
Hunter's Guide to Long-Range Shooting - Google Books
I thought that only applied to artillery. Holy Crap! :eek: I allways figured that it was the direction of the rifling that made the bullet veer left or right. The 1903 Springfield twists one RIGHT turn every 10" and will drift to the right. The Enfield one LEFT turn every 10" and will drift to the left. The bullet is dropping as it flies and at 2700 FPS or so, I thought the spin of the bullet actually rolled the bullet in the direction of the spin because the greater preasure against the bullet, besides the tip, was to the bottom where the bullet was starting to fall while still maintaining it's original line of axis when it left the muzzle. Kind of like rolling on the surface of water. Whew! It's all very complicated to me! :runaway:
There are two effects. Coreolis effect is the movement of the earth while the bullet is in free flight. Magnus effect is the rotational effect of the bullet acting on the fluid ( air ) it is traveling in and depending on the deflection of the bullet nose and center of rotational mass causes the bullet drift not attributed to wind or air movement.
Yep. the 1903 Springfield sight and the Krag's 1901 sight automaticly adjusted for this "lateral drift" as the range increased. The Enfield's rear sight did not.
From SEAL Sniper Training Program 1992
Temperature differences between the rifle and target have an effect as well.
"Mirage also has a density in addition to direction :
Thick density
High temperature or
High Humidity or
Bright light
Thin Density
Low temperature or
Low light
At 1000 metres (1100 yards) a 10 degree change in temperature necessitates a +1 minute of angle adjustment (thats 11" at 1100 yards)
Elevation above sea level also has an important effect on bullet trajectories. At higher elevations, both air density and temperature decreases, and air drag decreases. At higher elevations the sniper tends to shoot high".
Summary - before taking the shot you need to know :
Direction of shot (North, South, East, West) (Coreolis effect)
Direction of bullet rotation (Magnus effect)
Wind strength & Mirage effect
Elevation
Temperature
Or if one is using minute of Duce and a Half ( 2.5 ton truck ) Kentucky windage and elevation will work. :lol:
Boy lots of things effect the bullet in flight, temp, air, earth rotation, and bullet spin.Quote:
Originally Posted by JBS
During the last wars, it was found that most shots were taken under 300 yrs, even for snipers. So a lot of those effects are not really relevent today except for long range snipers and target shooters.
Back to my original question as I'm really curious. If my rifle shoots 3-4" right at 100 yrds, how far out would the
Magnus effect effect bring it center target. I'm thinking maybe 500 yrds? I'm only saying that because that's what the longist yard position that the base sight in the down position can be adjusted to. Ray
If the Coriolis effect has any measurable influence on a bullet, then it will depend on the direction in which you shoot!
Beat Kneubuehl, in his two books on ballistics and projectiles mentions the Magnus effect, but not Coriolis. So I supect that the effect is for practical purposes undetectable, or, as a friend used to put it: "A difference that makes no difference is no difference.
Patrick
Darn it, sorry I meant Magnus effect. I'm slipping.
If my rifle shoots 3-4" right at 100 yrds, how far out would the
Magnus effect bring it center target. I'm thinking maybe 500 yrds? I'm only saying that because that's what the longist yard position that the base sight in the down position can be adjusted to. Ray
Hi there,
just come across this query about the long lee enfield, it seems there are few around so heres hoping someone can help.
I recently acquired 1902 long lee but it doesnt like modern ammo. I was given 215gr round nose heads which after resizing the cases some were loose or fell into the case. I bought a new LEE deluxe set and the same is happening again some fine whilst others loose, although 174gr sierrra have no problems. measured the bullets and both seem to be the same size. the 215 does have a cannelure which not sure makes a difference.
Anyway almost giving up on the 215gr (lucky i had a bullet puller or 100 cases would be used up to no avail.
anyone who shoots the long lee is there any other bullets thay they would advise to try?, I have had the bore measured with cerrosafe which almost ended in a deact!!!!! and tried to slug with lead shots but not a true measurement was made.
interested in the 215g KYNOCH ones shown in a previous thrad but cant open the site.
any help very much appreciated
douglass
Here is the link again :
kynoch nitro express cartridge range from .240 to .700
If that doesnt work try putting Kynamco into google and it should bring it up.
i thought that the mkvII ammo would destroy the rifling in the barrel of that older rifle
The old original ammo was loaded with a 215 and Cordite Mark I, which was really hot stuff. MV was 2060 ft/sec in the Mark VI version.
When the Mark VII came in, they started using Cordite MDT 5-2, the 174-grain triplex composite bullet and the MV increased to 2440 ft/sec.
Cordite MDT burns a LOT cooler than the original Cordite Mark I and so the effect is to prolong your barrel life.
BTW, you should be gaining about 100 ft/sec over the official speed with that Mark VII ammo in the old rifles; that extra 6 inches of barrel does make a difference. My 2250 ft/sec handloads for the SMLE clock at 2335 in a Ross with a 30-inch barrel.
Is there a current manufacturer for a 215-grain RN .312" bullet? Now that I actually HAVE a very nice Long Lee with a good bore (although factory-sportered about 90 years ago), it would be nice to try it with 'correct' ammunition. Be good for the LM Mark II commercial as well..... get a comparison of II, VI and VII loads and do it all the same day.
thankyou,i just thought that the higher muzzle velocity would wear down the barrel faster