Cheap conversion to micrometer seater

[Nomad47]

Here is a way to convert a straight seating die to a "sort of" micrometer seating die.
Pictured is a wheel divided into 36 segments which is what the thread pitch is for a RCBS seating die. A friend created a drawing using a computer drawing program and emailed it to me. I have a screwdriver that has the blade bent 90 degrees (for tight places). It makes a great pointer.
For a Redding seater the wheel needs to be divided into 50 segments. And I don't know for other seaters.

 

[P1ZombieKiller]

genius???

 

[Dans40X]

You may want to re-count the thread pitch on your RCBS seater stem!!
#10-32tpi to .22
1/4-28tpi .25 & up

 

[Nomad47]

You may want to re-count the thread pitch on your RCBS seater stem!!
#10-32tpi to .22
1/4-28tpi .25 & up

And what is in between .22 and .25?

Every one of my RCBS dies has been 28 TPI and that includes 22-250, 223 wssm and 243 calibers.

 

[firearmdoc1]

I may be missing something, but if an RCBS seater is 28 tpi, why would you make a scale diviced by 36?

 

[Dans40X]

Exactly!!!!!!

 

[Nomad47]

I may be missing something, but if an RCBS seater is 28 tpi, why would you make a scale diviced by 36?

Well, when you have 28 threads per inch, each thread is .0357" long (divide 1 by 28). So that means one full turn moves the bullet seat up or down .0357" (let's round that off to .036" or 36 thousandths). 1/2 turn would be 18 thou, 1/4 turn would be 9 thou, and 1/36 turn would be 1 thousandth.

 

[Dans40X]

Yes,I know the math-

The class1 thread will be an issue.

I prefer straight line seaters w/ mic thimbles already attached!

 

[Nomad47]

Whatever. It sure didn't sound like you knew the math.

Prefer what you want, I was simply pointing out that there is a way to take some of the guesswork out of the cheaper dies.

 

[bsekf]

Great idea but wouldn't the tension of the lock nut influence the precise measurement? I use a similar system on my Forester BR seating dies, I just didn't make the dial. I just know 1/32 turn = about .001

Bill

 

[tdnichols651]

Redding sells an conversion for their dies...$35.00...cheaper than new mic dies..and can be purchased for regular or VLD bullets...

 

[SBS]

An ATTABOY for Nomad, who apparently wanted to share some good info. with those of us who still use only stems and locknuts on some calibers. Much appreciated.

 

[firearmdoc1]

Nomad,
Thanks for the explanation! Guess I just didnt think about it enough before I posted. May not be as good as a micrometer seater, but still good info for those of us who either can't afford one or don't need the accuracy of one.
Thanks

 

[Nomad47]

Great idea but wouldn't the tension of the lock nut influence the precise measurement? I use a similar system on my Forester BR seating dies, I just didn't make the dial. I just know 1/32 turn = about .001

Bill

Doesn't seem to, Bill. But I never loosen the locknut - just keep it snug enough that the screw can still be turned.

Thanks, SBS. Your comment is appreciated.