Ammunition Warning

Ammunition Warning

After extensive testing, we have found that only ammunition manufactured to SAAMI (Sporting Arms and Ammunition Manufacturers Institute) specifications is reliable in Calico Light Weapon Systems firearms. Calico Light Weapon Systems recommends the use of high quality, domestically produced ammunition for best results and highest accuracy. For plinking and practice, we recommend only domestic, commercially manufactured ammunition. Please note: the use of hand-loaded ammunition voids the factory warranty. The use of all ammunition listed below also voids the warranty.

We have incurred feeding problems with the following:

  • Israeli ammunition
  • Korean ammunition
  • Chilean ammunition
  • Portuguese ammunition

We have reviewed several reports, from several manufacturers’, regarding problems using this ammunition. The problem appears to be the bullet contour and the overall length of the cartridge, which is contacting the rifling before firing. This is creating a gas port pressure and chamber pressure higher than recommended, therefore causing feeding and extraction problems due to the increased bolt carrier velocity. In addition, there is accelerated fatigue on internal parts. There are also indications that brass may be out of spec, which could create an unsafe condition.

  • PMP
  • South African produced surplus

We have used this ammunition in the past for testing purposes and found the brass is extremely soft and can “flow” into microscopic pores and grooves in the chamber creating “sticky” extraction. This has been reported in many types of rifles, but is more prevalent in semi-automatic weapons.

  • Lacquer Coated Ammunition or Steel-cased, lacquer coated ammunition
  • Wolf
  • Norinco
  • Silver Bear
  • Any steel-cased (coated or non-coated) ammunition

The problem with this ammunition is that the lacquer coating on the case. As the barrel heats up, the lacquer turns to a soft, varnish substance and upon cool down, becomes very solid and difficult to remove. This effectively creates an undersized chamber and creates understandable problems.
Your rifle is an investment and it only makes sense to choose quality ammunition for a quality rifle!

Barrel Information

To achieve the best results for accuracy you should clean the chamber and bore after every round for the first 25 rounds and then every 10 rounds up to the 100 rounds. It usually takes about 300 to 600 rounds per barrel for optimum accuracy. Please keep in mind that our barrels are production barrels not custom barrels. Accuracy is dependent upon many factors such as bullet weight, powder load, rifling twist, rifling lands, operator technique, etc. Our production barrels have achieved anywhere from 1/8″ to 1 ½” M.O.A. Obviously, we would hope that every production barrel would shoot 1/8″ M.O.A., but with all of the above factors, we cannot guarantee a specific group size.