I’ve previously used the “cleaning rod down the barrel” method of measuring the overall cartridge length, with the bullet’s ogive just touching the lands. I found the major weakness to this system was the fact that having a recessed muzzle crown limited the ability to accurately draw, and measure the precise distance between, the relevant lines on the rod. Consequently, I would greatly appreciate any advice or opinions from the readers in relation to the following alternative method :
Method used for seating a bullet off the lands :
1. Partially insert a bullet into the slit neck of a properly sized, unprimed case.
2. Insert the dummy cartridge into the chamber and exert light pressure with a finger against the base of the case so that the bullet’s tapered nose or ogive makes contact with the barrel rifling grooves or lands.
3. Then, fully insert the case into the chamber.
4. Carefully extract the cartridge from the chamber – use wire hook in primer hole.
5. Measure the length of the cartridge, from the bullet’s tip to the base of the case.
Note : This measurement should be the maximum cartridge length for that bullet in that rifle, with the bullet’s ogive just touching the lands of the barrel.
6. Seat the bullet in a properly sized, primed case to a depth that results in a cartridge with an overall length 0.5 mm shorter than the maximum cartridge length – resulting in the bullet’s ogive being 0.5 mm short of the lands.
7. Test fire several cartridges – check the PRIMER pressure levels etc and overall grouping size – further reduce the cartridge’s overall length if required.
Note : 1. Use a fine hack saw to cut the slits and remember to remove any burrs. The slits reduce the frictional force on the bullet, allowing it to easily slide into and out of the neck. There is also less chance of the bullet being tightly jammed in the lands when the case is fully inserted into the chamber.
2. Drill the case’s primer hole out to about 3mm.
3. Shape a small hook at one end of a thin, stiff piece of wire – to be inserted into the enlarged primer hole and gently pulled to extract the cartridge from the chamber - rather than using a rifle’s more forceful ejection system which will possibly change the bullet’s precise position resting against the lands.
4. Using the above method, I recently loaded a batch of Hornady 65 Gr V-Max bullets for my beautiful old Browning B 78 High Wall .243 Win single shot rifle – resulting in a very respectful tight group. In the process, I’ve seated the bullet 0.6 mm short of the lands, resulting in only 2 mm of the parallel sides of this boat tail bullet making direct contact with the case’s neck. Could someone possibly inform me if there is any absolute minimum length for seating a bullet inside the neck of a case, and if there are any associated safety & performance issues. I’m conscious of the fact that, with such a small contact area, any rough handling might easily put the bullet out of alignment in the case’s neck. I’m new to reloading and often search such forums on the internet for helpful advice, one being the suggested starting point of seating a bullet about 0.5 mm short of the lands. My sincere thanks for any feed back.