HA2 11.1 – Heretic Way of Annealing

Once they managed to re-size 500 pieces of used-cartridge, Hide took Takeo and Shizuka to annealing step. He opened the class by taking a piece of 1 mm thick steel wire and held it with both hands in front of Takeo and Shizuka.

“Watch this,” Hide said as he bent and then straightening the steel wire repeatedly. “Tell me what will happen if I keep bending and straightening this steel wire.”

“You will break it,” Shizuka hesitantly replied. “I think.”

“And why is that happened?”

“It’s because the motion from bending and straightening change the molecular structure of the steel wire, and the steel wire becomes brittle,” Takeo firmly replied.

“Correct,” Hide stopped his hand as he continued his explanation, “And one of the methods to put the molecular structure of metal back into its original form, free of stress, is by giving it a heat treatment, and we call this heat treatment annealing.”

“So, after we re-size it, we will give the cartridge annealing,” Shizuka asked.

“Correct,” Hide firmly replied.

“How many times we can anneal a used-cartridge?” Shizuka asked another question.

“Similar to how many we can re-size a cartridge, it depends on the cartridge’s quality. For example, Joe Entrekin, one of best score shooter on earth, he has 40 plus reloads on his regularly-annealed brass. In short, as long as a cartridge passes the re-size step, we can anneal it.”

As question mark appeared in his forehead Takeo asked, “Don’t the manufactures worry their sales will drop if people can reload their cartridge?”

“Well, every ammo manufacture follows its own philosophy. Some will treat the reloading as unforgivable heresy, while some other will support it as a healthy hobby.”

“Wait a second,” Takeo’s eyes widened as he continued, “some ammo manufacture actually supports it?”

“Like I said, they have their own philosophy. For example is Norma, they love to repeat a quote from Rudyard Kipling, ‘A man can’t never have too much red wine, too many books, or too much ammo.’

And so, they produce cartridge that strong enough to withstand high pressure, but flexible enough to be re-drawn to its original size so the reloader can fire it as many as possible.”

This text was taken from Royal Road. Help the author by reading the original version there.

“That’s really a weird business conduct,” Takeo said in puzzlement.

“Norma even takes the pride that reloader can expect more reloading from their cartridge compare to equivalent product from other manufacture.”

“I see,” Takeo calmly said.

“Well,” Hide casually said, “Let’s start the annealing.”

When annealing used-cartridges, people usually used a combination of blow torch and holder that had a shape like revolver. The holder would rotate clock wise and put the cartridge right under the blow torch for certain amount of time. The user then took the cartridge that had been exposed to the heat and replaced it with other cartridge. This method was very popular because it was affordable.

In the firearm workshop, Hide also found this type of annealing equipment. However, he chose to use fancier equipment. It was electric furnace that could be used to anneal used-cartridge in bigger number for each batch.

Swiftly, Hide arranged the used-cartridge into an annealing tray. It had 100 slots and he put the used-cartridge into each slot standing upward facing the heating element. After pre-heating the furnace, he then inserted the annealing tray and ensured so the tip of the cartridges only 0.5 cm below the heating element.

“Any question?” Hide asked as he closed the furnace’s door.

Takeo immediately lifted his right arm before asking, “How high the temperature we use and for how long?”

“It depends on the alloy that being used to produce the cartridge. As far as I know, it ranges from 150 to 800 degree Celsius, with minimum duration of three seconds. To know the correct temperature and duration, we have to look the reloading manual and do some trial and error.

Fortunately, this workshop has reloading manual issued by Norma, Remington, Hornady, Lapua, and some other manufacture. Other than that, lot of reloader in Americ shares their experience in internet.

For our 9 mm round, I find a reference that 200 degree Celsius for 3-4 seconds is the best recipe.”

“I see,” Takeo calmly said.

“There is also an old school annealing that doesn’t employ technical approach. It only suggests the re-loader to expose the cartridges until its neck slightly glowing red before taking it out of the fire.”

“Is it okay to use such method?” Takeo curiously asked.

“When we don’t have equipment capable of highly-precise measurement, we will use that old school method. In my experience I find it work good enough. Lot of seasoned gunsmith in Americ also employs this method.”

“I see.”

“Well, let’s set the temperature and duration.”

Without delay Hide set the electric furnace at 200 degree Celsius for 3.5 seconds. A moment later the heating element on the furnace’s ceiling turned into glowing red, and just as the tip of the cartridges slightly turned red, the heating element suddenly dimmed before returning into its original gray color.

“Is it done?” Shizuka curiously asked.

“Yup,” Hide calmly replied as he opened the furnace’s doors.

“Is it okay to only harden the cartridge’s neck to the heating element? Don’t we should flip it?”

“First, we are not cooking the cartridge,” Hide calmly replied. “Second, the neck and the shoulder is the part that received the most stress both when the ammo is being fired and when the cartridge being re-sized. Therefore, those two sections become the area with highest brittle level.

Also, the main purpose of brass annealing is not to harden its molecular structure. Unlike steel, brass is not hard but elastic metal. We use the heat to melt the brittleness and put the molecular structure back to its original form and elasticity level.”

“Wait a second!” Shizuka said as puzzlement filled her eyes. “In short, the annealing is not to re-harden the brass?”

“Yup,” Hide casually replied, “and actually you can’t produce a cartridge that too hard. If a cartridge is too hard it will definitely split or crack when being hit by high pressure. What you need is a cartridge that resilient enough to withstand high pressure as high as 60.000 pounds per square inch at minimum, and high heat that can melt most steel.”

“I see,” Shizuka said as if she just received enlightenment.

Hide then calmly took out the annealing tray and moved the cartridges into a stainless steel tray to allow it cooling down. After that, he turned his gaze to Takeo and Shizuka.

“Give it a try. Wear your heat-proof gloves. It will protect your hand and ensure you don’t leave your fingerprints,” Hide calmly said

“Okay,” Takeo confidently replied.

At the same time, Shizuka dejectedly looked at Hide while taking a deep breath. “Hide, honestly, I don’t fully understand your explanation, but I think I can repeat the annealing step you just show me.”

“That’s more than enough and have no worry,” Hide assuredly said, “I will prevent you go astray from the Heretic Way of Annealing.”

“Okay,” Shizuka replied in tone full of relief.

Without delay Takeo and Shizuka then repeat the annealing step for the rest of the cartridge.

*****