Sometimes you need to perfect your tools

Munkey1973

Munkey1973

CGN frequent flyer
Rating - 100%
79   0   0
Location
Regina, SK
Years ago when I began reloading for F Class (bump sizing in particular), I always though "wish they'd sell these rings with an indicator."
I used to dream of buying a Tormach 770 or 1100 and do some hobby machining.

But instead I got a commercial grade Fiber Laser last week, and have turned out my first, fun little project.... and hopefully it will be useful as well.


Going to try it out tonight.

ARpcBWy.jpg
 
Last edited:
G_Alan said:
Thats really awesome, good job look's great.
Click to expand...

Thanks friend, appreciate the compliment!

The very first one made didn't look as nice!
My measurements for the inner diameter were off by about 1.2 millimeters on my CAD which was just enough for the laser to engrave past the inner beveled edge... which lead to "serrated threads" half the way down since the tips of threads are of course very thin LOL.
 
Last edited:
Redding competition shell holders are 2 thou increment for a bump, what is brass spring back, 1 thou or more?
Just curious where this fits in?
 
freire said:
Very nice job I like it.
Click to expand...

Thank you.

call2arms said:
Great work! Sadly I use a permanent marker when doing similar reference marks
Click to expand...

Thanks as well..... don't be sad... bet you that if we took a poll on this forum that probably 80% (maybe more) have used a marker.

In fact, I will still have to use a marker on the threads of the die.
Only now, my ring should (mathematically/theoretically) provide a consistent means for gauging the incremental movement of the die up or down.
 
Hitzy said:
Redding competition shell holders are 2 thou increment for a bump, what is brass spring back, 1 thou or more?
Just curious where this fits in?
Click to expand...

I sold my Rockchucker 4 press and went with a Forster Co-Ax a few years ago.. so shell holders do not apply to me.

When I had the Rockchucker I thought of taking this route (Redding Shellholder).

Even if still had a traditional style press, I think I could still make possible use of this ring.
 
Last edited:
Years ago I bought the PMA micro sizing die adjustment ring. Have many of them and they work great. No marker for me....

The other thing I also have is a couple sets of die shims. Set the die up with some shims. Need a little more bump, take out a thou of shim. Work good to.
 
Very nice work.

I wonder though if with the full set of equipment and the subject of the sizing (the cartridge), if being able to adjust such small increments will consistently translate into the kind of accuracy you seek.

1. Is your press perfectly consistent? Play, etc.

2. Do you place a very consistent amount of lubricant on each cartridge?

3. Does lubricant build up in the die and affect the sizing?

4. Does all brass size precisely the same way? Springback, pull on the neck on the upstroke, etc.​

You might find after carefully measuring 100 sized cartridges that the brass is accurate to +/- 10 thou, so measuring to 2 thou is moot.

People weigh charges to .01 grs and even weigh primers, and beside peace of mind, can't demonstrate better results.

That said, a thoughful exercise and impressive results.
 
Andy said:
Very nice work.

I wonder though if with the full set of equipment and the subject of the sizing (the cartridge), if being able to adjust such small increments will consistently translate into the kind of accuracy you seek.

1. Is your press perfectly consistent? Play, etc.

2. Do you place a very consistent amount of lubricant on each cartridge?

3. Does lubricant build up in the die and affect the sizing?

4. Does all brass size precisely the same way? Springback, pull on the neck on the upstroke, etc.​

You might find after carefully measuring 100 sized cartridges that the brass is accurate to +/- 10 thou, so measuring to 2 thou is moot.

People weigh charges to .01 grs and even weigh primers, and beside peace of mind, can't demonstrate better results.

That said, a thoughful exercise and impressive results.
Click to expand...

They work. I’ve been doing something similar for years. But if you want consistency, properly annealed brass will do more to help than anything else.
 
cycbb486 said:
Years ago I bought the PMA micro sizing die adjustment ring. Have many of them and they work great. No marker for me....

The other thing I also have is a couple sets of die shims. Set the die up with some shims. Need a little more bump, take out a thou of shim. Work good to.
Click to expand...

I'm glad you posted this as I completely forgot the name of it (i.e. PMA micro sizing die adjustment ring).
I found a link once like 5 years ago on accurate shooter and this device was pretty much my inspiration for developing this ring.
But at $69.95 (USD probably) I let the idea go.

But even still, I would have much rather got the PMA instead of the Redding Shellholder set (probably the same price converted to CAD) because the Redding is predetermined increments versus the PMA which seems to offer whatever the user wants.

Tried the shim idea out on the Rockchucker.... was repeatable but I didn't care for having to reinstall the shims on die changes.
Never bothered with the shims on my Co-ax for obvious reasons.

Cheers,

Mike
 
They have been around six months or so. I bought a bunch when they first became available. The tick marks appear to be laser etched after anodizing.
 
chuck nelson said:
They work. I’ve been doing something similar for years. But if you want consistency, properly annealed brass will do more to help than anything else.
Click to expand...

Agreed!
They (similarly mine) do work very well.
The only real trick to consistently "walking the die down" is to maintain upward pressure on ring towards the top of the die as you tighten the cross bolt.
Die and ring threads have a lot of play, just have to consistently take out that play when its tightened up.

Tested mine out last night on my Redding 308 Type S F/L.

My fired case measured 1.6285 and I like to knock them back to 1.625.

Moved the die down until it kissed the co-ax plate then backed it off about 1/3 of a turn.....
Figured with was way more than necessary when I did it -and I was right way too much (table below).

Marked with a sharpie at 0 point on the die body and ran it through.
As expected, the headspace actually grew to 1.631 b/c the die had not yet come into contact with the shoulder.

I figure I could have done it with way less attempts if I had just backed the die off an 1/8 of turn instead of 1/3 on initial set up.
Gently walks in down without overshooting the mark...Wish I had other calibers to reload instead of just 308 Win.

aBjE8dl.png


IKaLK2J.jpg


2hLjOMt.jpg
 
There's a YouTube video with Erik Cortina discussing how he does this.

As I recall, he measures from the bottom of the lock nut to the bottom of the die.

The problem with that is unless you measure at the exact same spot on the nut every time, you won't get relevant measurements.

I prefer to do what you've done, which is move the lock nut in measurable increments.

And as Chuck said earlier, annealed brass makes the process much more repeatable. Hard brass springs back more than soft brass.
 
Munkey1973 said:
Years ago when I began reloading for F Class (bump sizing in particular), I always though "wish they'd sell these rings with an indicator."
I used to dream of buying a Tormach 770 or 1100 and do some hobby machining.

But instead I got a commercial grade Fiber Laser last week, and have turned out my first, fun little project.... and hopefully it will be useful as well.

If my math was right ... every 10 degrees of angle for a 14 TPI pitch ought to be 0.002 of an inch movement on the die.
1 revolution = 1/14 = 0.071429 = 360 degrees
Therefore, if one degree is 0.000198 .... then 10 degrees is pretty much 0.002 ... does this sound right?

Going to try it out tonight.
Click to expand...

Any chance you could share some info on the laser unit...? I'm window-shopping for one...

Thanks...
 
You must log in or register to reply here.
Back
Top Bottom