Rear sight adjustments when using reduced load .303

[nagantino]

I’m going to load some .303 using the Lee 158 cast lead bullet. Others have mentioned Titegroup as a good powder using 8 grains as a starting point. I’m guessing that, at 100yards, some adjustment to the rear sight would be needed. I’m thinking of raising it to 400 yards. Anyone tried a similar combination?

[Mk42gunner]

I haven't tried that particular combination, but do have two suggestions.

1. Use a big target.

2. Start closer. Like 25 yards.

Good luck

Robert

[Winger Ed.]

Try it.
You should at least be on paper with a large 100 yd. target.

[pworley1]

I usually start at 25 yards and work back from there.

[Bigslug]

Your sights are most likely calibrated for the MKVII 174 grain spitzer at around 2450 fps.

A lot of us replicate the older MKI-MKVI 215 grain / 2000 fps load with cast bullets like the 314 or 316299. With that load, I've found the battle sight peep on a No.4 (which should work out to 300 yards with MKVII) to work pretty well at 100 yards.

Ian McCollum of Forgotten Weapons recently posted a vid about a Soviet suppressor that was made for use with subsonic loads out of a Mosin-Nagant. The cool thing about it was that the suppressor was stamped with the sight settings you should use to compensate for the slower ammo. As I recall, it required cranking the rear sight up to 700 meters for a 100 meter zero, and it went up to the 1200 meter setting for 300 meters.

For such projects, I usually just take a SWAG and sight in on a milk jug, adjusting off of dirt splash until I impact. Then I go to paper to fine tune.

[gwpercle]

With reduced loads in a battle rifle ... start at 25 yards ... then 50 yards (this is about where I shoot these loads) next , if you are getting groups , not patterns ... move to 75 yards ...
Then if you are still getting good accuracy ... go for 100 yards !
It's easier to adjust the sights as you go ... shooting and making small adjustments ...trust me on this !
Good Luck ,
Gary

[BLAHUT]

Start close then move out 25 at a time to what ever yardage ??

[Hick]

I'm not sure which sights are on your 303-- mine is a Mk3* (1936 vintage). I shoot all sorts of bullets from 130 to 190 grains, using titegroup and HP-38, velocities from subsonic to around 1800 fps. I don't think of the sight in terms of yardage, but use it merely for the numbers. So, for example, at 100 yards the sight setting for my 170 grain spitzer at 1360 fps is 6.6 (the third little mark between 6 and 7 on the sight). This approach will work for just about any load.

[dverna]

With reduced loads in a battle rifle ... start at 25 yards ... then 50 yards (this is about where I shoot these loads) next , if you are getting groups , not patterns ... move to 75 yards ...
Then if you are still getting good accuracy ... go for 100 yards !
It's easier to adjust the sights as you go ... shooting and making small adjustments ...trust me on this !
Good Luck ,
Gary

Good advice

[Outpost75]

With my No.4 Mk1* Long Branch the NOE clone of #314299. loaded as-cast and unsized with no GC shoots on at 100 yards with the Mk2 battlesight flipped to 500 yards using a powder charge to reach 1300-1350 fps, about 12 grains of #2400 or 15 grains of 4227

[303Guy]

My 303 carbine is shooting way lower than the boolit velocity would account for for some reason. This at 25 yds. With a higher pressure load it shot fairly close to bore line. This rifle, like all of mine, has a free floating barrel. I have wondered how a full length fore-end clamped onto the barrel would influence it.

Anyway, as it is, different loads shoot to different heights. Another rifle I tried with subsonic loads shot very low, way lower than line of bore. That was a 210 gr boolit on top of 5grs Clays. That boolit may have been slow enough to account for the drop, not sure.

[samari46]

Don't know about the No.1 mark 3 but all the front sights on the No.4 series of rifles are stamped with the heights of the front sight. All the blades are the same size except the bases which vary in height. Never tried it myself, but swapping out the blade for one higher may help you lessen the adjustments on the rear sight. Depending on the height of your current front sight blade may have to go one or two more numbers. Liberty Tree has the front sight blades but they don't (as far as I know) separate them according to size. Frank

[Jack Stanley]

The advice of starting at twenty-five yards and working out from there is very good . Watching group size likewise excellent .

The gallery loads for my 1903 are perfect out to about forty yards , at a hundred I need more elevation , lots more .

Jack