How To Anneal

FIRST, make sure there is no gunpowder or live primer in the case. Then you want to heat the neck and shoulder with a hot, concentrated flame that delivers heat rapidly to all sides of the neck area ONLY. How you deliver that heat is the function of all the annealing models on this website. The neck needs to be heated hot enough to alter the grain structure, which requires both time and temperature. How hot? How long?

Changes start to occur in brass grain structure at 480 degrees fahrenheit. To properly anneal brass, the temperature needs to be at 650 degrees F. for several minutes--BUT this will transfer too-much heat to the lower case in that time. So we need more heat for a shorter time. We need to raise the neck temp to about 750 degrees F. only for a few seconds to anneal.

CAUTION: Do not anneal any other part of the case. An annealed base (head) does not have enough strength to support the high gas pressures of combustion and may rupture, resulting in injury, which is why you can't put the cases in the oven to anneal.

Annealing PhotoThere are several methods of determining when you have reached proper annealing temps: applying temperature-sensitive liquid (Tempilaq is recomended and available from McMaster-Carr or welding supply stores), or digital air-temp gauges, or watching for a specific color-change in the brass. Properly annealed brass necks and shoulders will be shiny light-blue or blue-grey. If you lose the shine, you got too hot. Do not let the case glow or get red-hot, that is too hot and you will be over-annealed.

Liquid Tempilaq

This picture shows liquid Tempilaq applied down the case and inside the neck. (We find the liquid superior to the crayons.) The Tempilaq has turned black on the neck, but not further down the case. It is not necessary to do every piece of brass, just on your test pieces when you are setting up the annealer. When it is applied inside the neck, you get a true reading on temperature reached, because the liquid is out of the direct flame.

 

Some older or dirty brass cases will not turn color, you can try polishing the case or using another method for determining the amount of heat necessary to anneal.

One popular method of determining when your case is at the right temperature, is to anneal at night in a darkened room. Apply heat to the necks until they just start to turn DULL MAROON and then leave the heat source. Remember, it is temperature and time that anneals, not highest temperature reached by your brass. That's why we normalize temps a few seconds before dumping in water or on the cooling tray.

Night AnnealingBUT, if you see dull maroon or red in a lighted room, you will be applying too much heat and be over-annealed. After heating, longer cartridges can be air-cooled, shorter cartridges should be dropped on a damp towel or in water to prevent too much heat from reaching the base. Use your personal preference for this cooling step for longer cases.

 

 

 

When first starting, most individuals will have a tendency to under-anneal, which causes no harm but does no good.

Over-annealing actually takes a good bit of heat, or the case has stayed much too-long in the flame.

How do you know if your neck is over-annealed? It will be dull. You can actually squeeze the neck opening from round to oval shaped with your fingers when the neck is overannealed.

Annealed Case

In the photo to the left, the .308 case on the left is properly annealed. The blue-grey color change runs down the case to just below the shoulder, and the brass neck is still shiny.

 

If the neck/ shoulder area is hardened, it is more prone to splitting or poor performance. This is what happens with repeated use.

As far as reloading sequence: You should deprime, then clean, then anneal, and then resize your case.