303 british Mark VII cartridge loading problem

[Ganderite]

The OPs challenge is to duplicate the POI of the Winchester 180 gr ammo with handloads.

Thew issue won't be velocity, etc,. but barrel harmonics and the other rifle issues. The only way I know to do this is to load ammo and shoot it.

 

[bigedp51]

There are two ways to tune a rifle for accuracy, vary the powder charge or change the up pressure at the fore end tip of the rifle. Both methods will change how the barrel vibrates to find a accuracy node.

With issued military ammunition the No.4 Enfield rifle was to have 2 to 7 pounds of up pressure at the fore end tip for tuning accuracy. Once the best up pressure and smallest group was achieved the front sight blade was changed for the correct POI at 100 yards.


REME Precis No. SA/Rifles/3 (Zeroing of No.1, No.3, No.4, No.5 Rifles)
http://www.milsurps.com/content.php?r=331-REME-Precis-No.-SA-Rifles-3-%28Zeroing-of-No.1-No.3-No.4-No.5-Rifles%29

 

[jethunter]

The OPs challenge is to duplicate the POI of the Winchester 180 gr ammo with handloads.

Thew issue won't be velocity, etc,. but barrel harmonics and the other rifle issues. The only way I know to do this is to load ammo and shoot it.

yes again.

I've worked lots of loads to match fixed iron sights and there is no way except shooting. You can make an educated guess to get a ballpark idea but you have to shoot and adjust the load.

Most people are surprised to learn that at 100 yds:
- lowering the velocity will raise the poi
- raising the velocity will lower the poi

Don't make windage adjustments until you have the vertical zero dialed in. Adjust the powder charge to get vertical zero and then adjust windage if needed.