Forster micrometer vs brass

[Wapiti1]

For annealing a bunch of brass, I do what Wrench suggests, but in a baking pan. Stand up 30 or so cases, fill with water to 1/4" or a bit less below the shoulder, and heat each case with a torch. Dump them all out, do it again.

The Lee collet dies are the way to go for simple and consistent.

I'm curious when a variation of 0.002" matters.

Jeremy

 

[steffen707]

For annealing a bunch of brass, I do what Wrench suggests, but in a baking pan. Stand up 30 or so cases, fill with water to 1/4" or a bit less below the shoulder, and heat each case with a torch. Dump them all out, do it again.

The Lee collet dies are the way to go for simple and consistent.

I'm curious when a variation of 0.002" matters.

Jeremy

What is tolerance stacking or stack-up?​

Tolerance stack-up is the process of adding tolerances together before manufacturing in order to understand their cumulative effect on part production. Final results from a tolerance stack are compared to tolerancing standards, regulations, and other limits in order to ensure the part design will produce high-quality components. This tells you the total amount a part can differ from specified dimensions.

 

[steffen707]

For annealing a bunch of brass, I do what Wrench suggests, but in a baking pan. Stand up 30 or so cases, fill with water to 1/4" or a bit less below the shoulder, and heat each case with a torch. Dump them all out, do it again.

How long do you heat up the case, or any particular surface temp you're looking to achieve?

 

[Wapiti1]

What is tolerance stacking or stack-up?​

Tolerance stack-up is the process of adding tolerances together before manufacturing in order to understand their cumulative effect on part production. Final results from a tolerance stack are compared to tolerancing standards, regulations, and other limits in order to ensure the part design will produce high-quality components. This tells you the total amount a part can differ from specified dimensions.

I'm an engineer and well aware of tolerance stack. It also doesn't answer the question. I understand trying to minimize variation with anything you can control, but does one cartridge being slightly off out of 100 have a measurable effect at the target?

Full annealing for cartridge brass occurs at about 800F. Many annealers target 750F and assume there will be some thermal increase to near 800 when the power is cut.

An easy method is to go into a dim room, and hit the brass with a torch until you just see it start to glow red. That is right about the 800F mark. Count out the time it takes for that, and you have a pretty consistent method. Brass is pretty forgiving when fully annealed, and overannealing is actually kind of difficult. The strength loss curve flattens when fully annealed. Most folks don't anneal it enough, and get inconsistent results.
Another way is tempilaq sticks or heat tapes that give you the exact moment it gets to the temp the stick or tape is calibrated to.

Jeremy

 

[steffen707]

I'm an engineer and well aware of tolerance stack. It also doesn't answer the question. I understand trying to minimize variation with anything you can control, but does one cartridge being slightly off out of 100 have a measurable effect at the target?

I doubt if everything else is identical that a 0.001" change in seating depth will be measurable at 100 yards.

I'm just trying to minimize as much as I can without breaking the bank.

I know i'm probably weakest link in my accuracy, but if the cartridge is as good as I can make it, I should do better and have more fun while learning to be a better shooter.

 

[wapitibob]

Stick the brass in the fully opened jaws of a portable drill, hold the case 90 deg to the torch flame, slowly rotate the case till the neck just turns orangish and drop the case on a semi wet dish towel. When done fold the towel over the cases and finish the cooling process and you're done. Heat can't increase once the flame is moved away from the case neck, nor can it increase and travel down the case body.

 

[Harvey_NW]

Your initial setup is the exact process I go through every time I set up a seating die. I always just figured there was some weird physics explanation that I don't care about because the results are consistent.

 

[steffen707]

Stick the brass in the fully opened jaws of a portable drill, hold the case 90 deg to the torch flame, slowly rotate the case till the neck just turns orangish and drop the case on a semi wet dish towel. When done fold the towel over the cases and finish the cooling process and you're done. Heat can't increase once the flame is moved away from the case neck, nor can it increase and travel down the case body.

I've watched an Erik Cortina video on his old annealer where he also said, "once it turns orngish he rotated to the next case. He used that nice dual torch spinning tool. I'm only doing 10-20 pieces of brass a week until I get my load dialed in.

I'll watch the video you posted and give it a shot.