Thread: .303 iron sights, Sporterized Long Tom.

So the idea is to sort Dads Long Tom for the lad down south.

It was plurry wet and slippery up the track, so only had a play at 100yds. I’m happy with the windage but it’s 19” high at 100.

When it’s drier I’ll go back to 200. The rear sight can’t go any lower, it seems to me I have to raise the front blade which sits in a lateral dovetail.

I have a Broad Arrow marked .060” front blade, but the dovetail is too small for the dovetail in the ramp.

I was thinking of building the blade up with Devcon and filing it down to get a 200yd zero. Then measure it with the Vernier and getting it built up with weld.

POA was lower dot.





Thoughts ?

B

My No 4 Mk 1* was shooting about 6” high at 100, as from memory they were/are meant to. I swapped my foresight for a +90 that brought the zero down to (near enough) 100. Trouble then was that ladder site calibrations didn’t match other distances. I understand the three oh is meant to produce approx 4 moa at 100 and if so, it not accurate enough for me. I flicked mine for Swedish 6.5x55.

nah mate...I think we have all made this mistake...the first notch was aim at belt buckle ...deer cullers held below brisket its how sights were meant to be used... our resident author will be along soon hopefully and chime in...he did a speil about how these origonal battle sights are meant to be used some time back.....
now heathens like me took to back sight with V file and made a deep V in it....ruined its authenticness but worked to some degree.

Originally Posted by Ingrid 51

My No 4 Mk 1* was shooting about 6” high at 100, as from memory they were/are meant to. I swapped my foresight for a +90 that brought the zero down to (near enough) 100. Trouble then was that ladder site calibrations didn’t match other distances. I understand the three oh is meant to produce approx 4 moa at 100 and if so, it not accurate enough for me. I flicked mine for Swedish 6.5x55.

Yes. From what I’ve read and looking at the marking on the rear ramp it’s a 200 yd zero.

It was Dad’s, so it’s not going anywhere, it has to be usable.

B

Originally Posted by Micky Duck

nah mate...I think we have all made this mistake...the first notch was aim at belt buckle ...deer cullers held below brisket its how sights were meant to be used... our resident author will be along soon hopefully and chime in...he did a speil about how these origonal battle sights are meant to be used some time back.....
now heathens like me took to back sight with V file and made a deep V in it....ruined its authenticness but worked to some degree.

Yes, deepening the V was a consideration, but a bit rangi bro…..

I’ll see what’s like at 200 then reconsider.

B

I set mine at 600yds to get a 100m zero with cast 215gn boolits doing around 1500fps.

Originally Posted by shift14

Yes, deepening the V was a consideration, but a bit rangi bro…..

I’ll see what’s like at 200 then reconsider.

B

Devcon on foresight could be the way to go rather than deep-notching rear sight. Consider building up the shoulders of front sight with Devon before making it taller. Once dry and hard, file to desired shape/height rather than butcher original steel.

Originally Posted by Ingrid 51

Devcon on foresight could be the way to go rather than deep-notching rear sight. Consider building up the shoulders of front sight with Devon before making it taller. Once dry and hard, file to desired shape/height rather than butcher original steel.

Those were my thoughts, though can’t see it being robust enough for hunting. Hence my thought of measuring total height from the base of the dovetail and building the blade up with weld, or brazing on a piece of fine rod for a bead on top of the blade, which is flat topped.

B

A low hold for open iron sights is less of a disadvantage because your sights then obscure less of the target.

40cm high is pushing it though.... Making the sight a bit taller with some Araldite (stronger, lead solder - just remove the bluing where you want the solder to stick to at the top of the post, heat to a sweat and apply a blob, file to desired shape) is a neat intervention that doesn't make any permanent change to a fine gun. These skinny money-strapped guys in the video paid a lot of taxes to manufacture it, so respect it.

What ammo are you using? The old longtoms were sighted in with the older 215gr pills, not the mk7 174gr military ammo, my long lees shoot quite high with 1950s mk7 174 ammo.

Greetings @shift14,
Lee Enfield rifles are notorious for shooting different loads to vastly different poi. If the rifle is a No1 rather than an earlier Long Tom it would have been regulated for 174 grain spitzer flat base projectiles at 2,440 fps at 300 yards. You are a lot higher than this but the rifle seems to shoot reasonably well. If you handload reduced loads with heavy projectiles may bring the poi down but the rifle will probably need to be sighted in for a specific load. A picture of the rifle and some details of the ammo would help.
Regards Grandpamac.

@grangpamac, thanks for your reply.

Pictures as requested







B

Originally Posted by shift14

@grangpamac, thanks for your reply.

Pictures as requested

Attachment 212526

Attachment 212527

Attachment 212528

B

That is an old one with that rear sight. It would have originally been regulated for 215 grain projectiles at a little over 2,000 fps so it is not surprising that it shoots high. A higher front sight would be the best option or an adjustable aperture sight if one can be found (unlikely). You can calculate how much higher the sight needs to be easily enough or I can calculate it for you (I just need the distance between the front and rear sights). Then it is a matter of finding a suitable replacement foresight or even filing a new one out of a block of steel. A milling machine would be faster.
A rifle similar to yours would have been used in South Afrika or early in WW1 by NZ troops. Troops at Gallipoli had rifles sighted for Mk VI ammo with 215 grain projectiles but were only supplied with Mk VII ammo with 174 grain projectiles which shot high. Probably made FA difference due to the ranges involved in the fighting. Nice looking rifle, deserves to be taken hunting. Might be best to find something else for the boy and keep it yourself.
Regards Grandpamac.

@grandpamac, sage advice thankyou.

Too many memories for me to use it. The grandfather he never knew, probably isn’t the father I did.

He’ll look after it well, and has ample opportunity to use it down south on Canterbury porkers if not reds, instead of his Sako 300WSM.

When things dry out up here, I’ll get back to 200yds and measure the drop on the plate with this ammunition.

FYI I measure 16 5/8” from the back of the vee to the back of the front blade.



B

Greetings again,
The ratio from the sight radius to the range to target is 1:218 (0.420:91.4) so to drop the POI say 450mm on target requires raising the foresight by a little over 2 mm (450/218). Others might like to check this for you.
GPM.