Headspacing gauge for a 243ai

[hunter243sgk]

I have been using a Hornady gauge for my other calibers but I cant find anything for the 243ai.What kind of gauge is everybody else using.I just need a accurate way to measure so I can set up my body die.Thanks!!

 

['Freak]

I like Sinclair’s. Instead of an orifice what’s supposed to be sized so it contacts the shoulder diameter very near the official datum line, Sinclair’s insert is shaped same as the entire shoulder area of the chamber.

 

[MrMajestic]

Larry Willis's gage.

 

[Patch700]

An easy way I have found that works on all cases that head space off the shoulder is to find out from the reamer print where it is that they classify the datum line and then make your own if you've the tools to do so.

For example , in the reamer print for 6.5x47 lapua you will see that the datum line is .3750" therefore if you had an insert for your tool that was .375" you would be measuring to the datum line.

Obviously not all inserts that you buy may not be precise to .001" (especially if they are aluminum) and as you probably know this is why one persons measurement is not gospel due to the variances possible between inserts .

Find out what the datum is and make your own , you'll find a lot of cases share a common datum depending on the angle of the shoulder so one insert can work with many others.

 

[hunter243sgk]

Thanks to everybody!!!I think I will see if I have what I need to make one first as I have the reamer print.If not I will try one of the other two.I have never heard of Larry willis gauges.Where can I find them?

 

[Patch700]

Here you go... scroll down some and it gives the AI dimensions along with datum line.

http://www.accurateshooter.com/cartridge-guides/243win/


I'd say if you were .367" you'd be good to go.

Good luck

 

[hunter243sgk]

Thank you sir!!

 

[MrMajestic]

I have never heard of Larry willis gauges.Where can I find them?

http://larrywillis.com/

 

[hunter243sgk]

Thanks MrMajastic!!

 

[Ackman]

I have been using a Hornady gauge for my other calibers but I cant find anything for the 243ai.What kind of gauge is everybody else using.I just need a accurate way to measure so I can set up my body die.Thanks!!

A headspace gauge to set the die? Why on earth would you use one of those? Setting a die is stupid simple. If you're wanting to make too-tight brass fit the chamber, it's just as stupid simple to set for a little bump. With an AI that should be very seldom - or never - necessary....just necksize. To see initially when the die is approaching the shoulder, a little caselube on the neck is all it takes. I use lead shot mixed with graphite and stick the caseneck into that......a graphite film is more visible.

 

[CatShooter]

I have been using a Hornady gauge for my other calibers but I cant find anything for the 243ai.What kind of gauge is everybody else using.I just need a accurate way to measure so I can set up my body die.Thanks!!

A headspace gauge to set the die? Why on earth would you use one of those? Setting a die is stupid simple. If you're wanting to make too-tight brass fit the chamber, it's just as stupid simple to set for a little bump. With an AI that should be very seldom - or never - necessary....just necksize. To see initially when the die is approaching the shoulder, a little caselube on the neck is all it takes. I use lead shot mixed with graphite and stick the caseneck into that......a graphite film is more visible.

^^^^^ What he said....

 

[hunter243sgk]

ACKMAN I use my LCD die to ns but every now and then I get a case that does not want to feed good.I have always had good luck with the LCD dies.I don't go for that fl sizing all the time like the majority of the people here do.And I do agree it works really well with the ai.But when you get one that wont feed good you got to bump it back a little.So since I had good luck with this in the parent caliber I thought I would do it like that in the ai.Also a more intelligent way to do what you said with the lead shot and graphite is to use erasable markers.Look at the posts before yours I most not be the only one doing this.Catshooter just why do you agree with him on this?

 

[CatShooter]

ACKMAN... [...]

Catshooter just why do you agree with him on this?

'cuz he paid me 50¢ to say it

Some people on this site make controlling headspace a mysterious secret ritual along with secret handshakes and incantations - it is not that hard.

Most people giving advice on headspace management are just repeating what they read somewhere - they never tried different stuff to see what really worked.

Ackman has been around the block, and done his homework.

.

 

[hunter243sgk]

Ha ha he paid you huh.I liked that one!!And yes I do agree a lot of people make to much out of that as well as other things that are not that difficult.

 

['Freak]

I like having a number from measured brass where if a piece of brass later on checks another half thousandth either way I’ll know whether that means that much more clearance or greater crush or if it’s at practically zero clearance and zero crush. Need to gut the bolt once for feel checking closing of the bolt whilst finely adjusting me die in search of that breakeven point and there on, I gots me a number for future reference.