This blog is not instruction.
Before beginning any reloading, take a class! This material only highlights areas that may be of interest for those considering reloading rifle ammo and all sections require training, further research and practice. This is NOT a step by step tutorial and do not use it as such. KJD Firearms Training offers reloading classes. Go to: http://www.nrainstructors.org/searchcourse.aspx to find the schedule and prices.
Sizing
Headspace
For rifle (bottleneck) shells, the term headspace refers to the distance from the breech face (bottom of shell) to the datum diameter of the shoulder . This is called the Datum Length (DL). Since the amount of shoulder bump is under the control of the reloader, the “DL” dimension can be matched to any chamber by proper adjustment of the sizing die. Redding’s Instant Indicator is one tool that facilitates this adjustment ensuring maximum case life and accuracy from handloads.
Headspace is critical. When setting up a resizing die, the final adjustment should be made using a chamber type headspace gage such as the RCBS Precision Mic or Redding’s Instant Indicator. The regular use of these gages will help to eliminate critical errors. Taking time to use these gages for initial setup and periodic quality control is time well spent. Additional details on the Redding Instant Indicator can be found in a separate post.
Dies
Note: Before resizing a case apply a lubricant to the case. Imperial Sizing Wax from Redding and Forster’s High Pressure Case Sizing Lubricant are two I found effective.
Two types of sizing dies can be used to size shell cases - Full Length or Neck sizing.
General guidelines are: Full length sizing die is used for reloading when: 1. reloads are used in a semi-auto or lever action. 2. used in more than one rifle. Neck sizing would be used if the rifle is a bolt action and the reloads will be used in the same rifle.
For semi-autos, the case needs to be Full sized - resized to the point that it will enter the chamber freely, completely and with absolutely no hint of resistance. The most common problem is the failure to fully chamber the round. Considering the force with which the bolt slams home, it can wedge the round tightly enough in the chamber that it is very difficult to extract without damaging the rifle.
With Neck sizing only the neck portion of the case is sized leaving the remainder of the shoulder and body untouched. Chambering a neck sized cartridge normally gives some slight resistance to closing the bolt. This is normal and while a minor problem with the camming forces of a bolt-action, this can be a serious problem with a semi-auto. It can cause a failure to fully seat and chamber the round and so jam the rifle. If the lugs have partially engaged, this is a very difficult stoppage to clear. So don’t Neck size for semi-autos.
Check primer pockets after de-priming. Inspect the web area and the flash hole for any burrs or obstructions. Clean, smooth primer pockets facilitates re-priming.
Neck Tension
With Semi-Autos, the abrupt stop the cartridge makes when the shoulder slams to a halt in the chamber, inertia will cause the bullet to slightly move forward. There are two options to counteract this force – applying a crimp or increasing neck tension. There are various crimp dies and the taper crimp fits the bill for my semi-auto rounds. Lee makes a “Factory Crimp” die and I have had some success with this die as well.
The other option is to increase neck tension – get a tighter grip on the bullet. Redding makes a bushing die (Type S Bushing Style Die). A bushing is inserted into the neck of the die. These bushings (usually made of Titanium Nitride) come in .001” increments. To obtain the correct size bushing, measure the neck diameter of several loaded cartridges with a caliper or micrometer. Subtract .001”-.002” from the smallest average neck diameter. This diameter bushing will generally size case necks to create the proper press fit for the bullet. Tension can be increased or decreased by simply changing the bushing size.
Select your dies carefully. As with all reloading equipment, the more research done, the better your selection will be. Various on-line stores such as MidwayUSA.com publish product reviews. Reading these reviews will save both time and money.
Note: There is reloading equipment for sale in many on-line stores such as E-Bay, Craig's list, etc. As always, the burden is on the buyer; read carefully and ask questions before purchasing used equipment. That being said, there are some bargains available for the persistent.
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