Reloading - Looking After The Brass Cartridge Case
Some older case designs will stretch quite quickly if fired using near maximum loads. There are tables available that show maximum and trim lengths. For many reasons these should be adhered to.
It is necessary to continually check case length.
If the case exceeds the maximum length, it may not chamber. This could be very inconvenient, and could cost you a trophy animal. It is also possible that if it fits in the chamber you may be faced with greatly increased pressures.
Once loaded, cartridges should be kept in suitable containers for transport and then if necessary transferred to a cartridge belt or other device if you have to do a lot of walking after game. As long as the rounds are protected from outside influences and are separated from one another, just about any type of case will do. Plastic, cardboard or combinations thereof seem to be most popular. At this point, we come to a parting of the ways as to whether we treat brass any further, and if in fact it achieves any useful purpose.
Brass should be stored in plastic or cardboard containers.
There are two distinct schools of thought. The first says that to do so is a waste of time, particularly if the rifle concerned is a stock standard factory offering. The second path relates to a rifle custom built to benchrest standards. In this case there is no argument. Brass HAS to be further treated if you wish to obtain the best results.
We left our cartridge case that had the primer pocket reamed, the neck chamfered inside and out, its length checked and a run through the normal sizing die.
Run new brass through the reloading die.
For some factory rifles it is possible that the next steps may assist in improving accuracy. The types of rifles that I am referring to are those factory rifles that are used for varmint shooting. We are looking at the various .22 calibre offerings and .243 calibre also.
With custom rifles built to benchrest standards, the turning of case necks to specified thicknesses is a requirement. This situation applies to pure benchrest rifles, as well as some rifles built to target live game at long distances.
Normal cases will not chamber in rifles that have tight necks.
The argument is that to carry out this procedure on a factory rifle is a waste of time as the greater tolerances within the rifles chamber will negate the advantages of this step. I am not so sure that this is totally correct. The accuracy buffs will claim that if the neck is not totally concentric, the bullet will tend towards the thin side of the case when the rifle is fired. Some recent experiments in the US indicate that even partial neck turning is beneficial to accuracy in a variety of calibres.
The requirement is to remove just enough brass to ensure that the case necks are as concentric as possible. For my .243 cases, the neck turning tool was set with a feeler gauge at .015 inches. It would not remove brass anywhere along the neck, and at .014 it started to cut. Every case left some uncut areas, usually at the neck mouth, the worst for a distance of 2 mm. Some cases were oval in shape and left uncut areas on either side.
Neck turning tool and feeler gauge.
You have to be careful and ensure that when you set the tool up you do not cut into the shoulder of the case.
During the manufacturing process the primer pocket flash hole is punched in the base of the cartridge case. It should be in the centre of the pocket. If not, discard the case. This process can also leave a small amount of brass protruding into the case surrounding the flash hole. This may have an effect on powder ignition. A small tool will remove this excess brass, leaving a small inner bevel.