Chamber casting for neck length

[robbor]

How easy is it to cast your own chamber?
Id like to check the neck length on a factory chamber so see hom much long my brass should be to have it fit as well as possible. I already know i have roughly .010 gap in neck diam from checking a fired round.
Do you recomend any other way to determing neck length?

 

[Cheechako]

Making a full length chamber cast while the barrel is in the action is not easy to do. There are little gizmos that are made to measue the chamber length. Very easy to use and not too expensive. Git hold of Sinclair. I think they sell them. At least they used to. If you are handy with tools you can make your own. Want instructions?

Ray

 

[robbor]

Yes now that you say it, I have seen the little plug that sinclair sells. It is inserted into the brass,probably one that was shortened) and then into the action and close the bolt and thats it, correct? Yes I could turn one on the lathe.

 

[Cheechako]

Yep, that's it. If you have a lathe they're a cinch to make. I make one for every rifle I own, even Grandpas old 30-30. I glue the plug in at the correct setting and keep it with the loading dies. Never a doubt about it and I never have to try and find my notes.

Ray

 

[chino1969]

robbor,
The device you are talking about is made from leaded steel, will not harm your chamber, and is sold by Sinclair. You trim approx. .200 off the neck of a re-sized case and insert the gauge. Chambering the round with the bolt closed, forces the gauge into the neck of the case. The gauge has a stepped o.d. that contacts the neck of the chamber before the freebore. Measure this dimension and subtract a certain dimension for safety and you know how long you can allow your case to grow until you have to trim. The Sinclair tool is cheap, easy to use and has good directions.
Chino69

 

[robbor]

Ya thanks. I have some fireformed brass that I can measure the neck on to get a firm fit. I will just have to decide what to make the pieces out of. I did check my sinclair catalog and notice the were listed as soft. To not damage. i would not guess that soft steel would be would be harder than soft or normal alum like 6061. Or I could try to bet a piece of copper/brass rod .