Is the No4Mk1 Lee Enfield "more accurate" at long range? FACT OR FICTION?
FACT (BUT WITH A TWIST): I can tell you with absolute confidence that starting at 500m the CNo4Mk1* really starts to shine in the accuracy department. Nope, I`m not on any medication. I’ll attempt to explain why the No4 enfield shoots better at long range.
I have chronographed variability in muzzle velocity within some IVI lots of +/- 120 fps with 175 grain Ball (FMJBT - full metal jacket boat tail) Mk8Z ammunition . That is a severe velocity spread (or standard deviation) and indicates possible issues with Quality Control with some ammo manufacturers. Having said that these were older lots from the early 1990’s. The good news is that IVI is now owned by General Dynamics Canada whom has significantly increased ammunition quality since then .
The way this works is as follows. Only caveat is that you keep an open mind . This might not be the answer you’re expecting.
Fast bullets exit the barrel sooner than slower bullets. There is normally some degree of standard deviation in cartridge formulation (powder charge, crimp strength, primer quality, etc) .
The relationship is as such: "The longer it takes for a bullet to exit the muzzle the higher the point of impact will be at shorter distances". “Why" ? you ask... As the slower bullet proceeds down the barrel the muzzle continues to rise due to recoil and barrel harmonics. This actually starts at the rear bolt lugs, through the action and continues on through the barrel. The No4 rifle is especially subject to this internal ballistics phenomenon – where-as the No1Mk3 SMLE is less prone to it because the forestock and nose cap play a limiting factor in barrel rise (where it doesn't in the No4Mk1).
Remember the No4 require 5 to 7 lbs of downwards foretip pressure for a few reasons, partially as a result of this and for shooting with bayonette attached.At short distances this translates why we can expect bigger group sizes when using poor quality ammunition. Slower bullets impact high and faster bullets impact low (vertical relationship not horizontal).
There is an exception though and this occurs at longer ranges.... Starting at about 500m the slower and faster bullets start to impact at the same point. Groups start to get smaller at long distance in relation to the shorter distances to target. Mind blowing stuff eh!
So in summary - YES the lee enfield is more accurate at long ranges when shooting low quality ammunition. It`s all in the ammunition! This phenomenon would not come into play if you had ready access to match grade ammunition.
Stay tuned and Maple Leaf Up
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