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Re: Lee Enfield No4 Mk2 - point of impact vs point of aim.
Posted: Sun Jan 24, 2016 6:15 pm
by dromia
Never a problem for me, just transfer the scribe marks and tap in the new one windage as before.
Re: Lee Enfield No4 Mk2 - point of impact vs point of aim.
Posted: Sun Jan 24, 2016 6:26 pm
by Explosive
dromia wrote:Never a problem for me, just transfer the scribe marks and tap in the new one windage as before.
That's OK if you know exactly what blade to install. I would not know, and doubt anyone else would either, it would just be a guess. Filing the blade a little at a time until spot on guarantees perfection.
Re: Lee Enfield No4 Mk2 - point of impact vs point of aim.
Posted: Sun Jan 24, 2016 6:31 pm
by dromia
Easy enough to do plenty of information out there on how to calculate blade height, really very useful. It will even tell you how much to file off your foresight.
Re: Lee Enfield No4 Mk2 - point of impact vs point of aim.
Posted: Sun Jan 24, 2016 8:44 pm
by TomEnfield
Thanks for the advice. Does any one know what the correct point of impact should be at 100m range with sights set to 200m?
Re: Lee Enfield No4 Mk2 - point of impact vs point of aim.
Posted: Sun Jan 24, 2016 9:24 pm
by TomEnfield
TomEnfield wrote:Thanks for the advice. Does any one know what the correct point of impact should be at 100m range with sights set to 200m?
Found out that PoI should be 3" above PoA at 100m
(Correction at Target X Sight Radius)/Range = Correction on Sights.
Correction @ Target =9"
Sight Radius = 28 1/2"
Range = 100yds = 3600"
Correction on sights = (9x28.5)/3600
Correction on sights = 0.07125
Blade fitted +.03
.03-.071 = -.041
Closest blade produced to -.041 is -.03
But before I change anything I need to get some groups with factory ammunition both PPU and S&B and maybe some of this new kynoch stuff...
Re: Lee Enfield No4 Mk2 - point of impact vs point of aim.
Posted: Sun Jan 24, 2016 9:39 pm
by Explosive
TomEnfield wrote:Thanks for the advice. Does any one know what the correct point of impact should be at 100m range with sights set to 200m?
That all depends on your load.
Re: Lee Enfield No4 Mk2 - point of impact vs point of aim.
Posted: Mon Jan 25, 2016 10:35 am
by nickb834
Explosive wrote:TomEnfield wrote:Thanks for the advice. Does any one know what the correct point of impact should be at 100m range with sights set to 200m?
That all depends on your load.
It does - but if the OP is using a repro load to match that generally issued then there's a specific answer.
I bought the full set of 9 blades - IIRC they're 15 thou different each, got em from this firm but looks out of stock:
http://www.ds-solutions.co.uk/ Perhaps worth a prod? They were dirt cheap as I recall.
Have a read through of this if you've not already seen it (Zeroing instructions - and probably the source of the formula to calculate which blade required):
http://www.milsurps.com/enfield.php?pg=ti15.htm
Don't bother with the site adjusting clamp - not necessary, drift the blade out - surprising how little force actually required.
TomEnfield wrote:Closest blade produced to -.041 is -.03
.041 isn't the closest - a .045 foresight suit you better if your correction is .041 - they're definately available as I have one in my set?
Lastly - if you have access to a 25 yard barrack range (or any other opportunity to shoot at 25 yards) then you may find the following useful also:
Siting targets
http://www.milsurps.com/enfield.php?pg=ti16.htm
EDIT: Just re-read your corrections and you need to come down not up - doh, my bad!
Re: Lee Enfield No4 Mk2 - point of impact vs point of aim.
Posted: Mon Jan 25, 2016 12:11 pm
by WelshShooter
I was just about to mention DS-Solutions but someone beat me to it.
I bought the full set of foresights for £15 so very cheap in my opinion. As a rough and ready approach, to find out what height you would need you can use simple trigonometry to adjust the height. You know the distance to the target, and you know the distance at which you want to move the bullets up by. You must calculate the angle subtended for this, then using the distance between the rear and front sight you can calculate the height of the blade required. Science!
Or you can, you know, just work your POI up by testing a shorter blade each time....
I would recommend making witness marks on your current front blade. You can measure this distance from the front post position and make the same adjustment on new front blades, that way you should be smack bang on for the windage.
Re: Lee Enfield No4 Mk2 - point of impact vs point of aim.
Posted: Wed Jan 27, 2016 8:52 am
by Maggot
A p*** easy way to measure your windage before you start drifting etc is to set the depth part of a vernier caliper on the foresight base and measure off of the foresight protector.
Just make sure you do it from the same side each time
Ovenpaa made me up a block that indexes into the protector with a flat ended machine screw that sits against the base of the blade (Flat bit that sticks out), just screw it in until it touches and unscrew the locking screw. You can easilly go back to where you want or elswehere in the range, no drifting, no hammers, simples.
Bolt out, adjust, bolt in, a few seconds, shoot again.
The screw is graduated (Im sure we worked out an actual move in moa but its not that accurate, simply marking both with a marker and locking the thread with an o ring works well).