adjusting head space

[boomtube]

Gene, "There is a need for someone to design a shoulder bump measurement tool."

Yeah. My best tool is from RCBS, it's their "Precision Case Mic". I also have the Stoney Point/Hornady tool and another one like Sinclair sells, but I like the Mic best because I get the most repeatable results with it.

The Mic has two top thimbles which screw onto the base unit. One thimble measures the case shoulder and the other measure the loaded bullets at the bore diameter of the ogive. I find the Mic really useful for this work.

The Mic also inludes a "free-bore" tool that is supposed to let us measure the length from the bolt face to the origin of the rifling. I suspect it would work pretty good with controlled feed actions but not for my push feed actions. So, I don't use that thing. I use a wood dowel for a bore rod and the bullet I want to load instead. Together, they show me the maximum load length quite well and it's done with simple "free" tools!

 

[woods]

lever-hed

I certainly don't think headspace measurements are futile and out of 41 different rifles I reload for I have the measurements of the gap between the shoulder of a new case and the chamber shoulder recorded for over 2/3 of them. They range from close to .010" to .030".

What I was referring to was the futility of explaining to someone how to adjust headspace on fired cases who is shooting factory ammo and talks of putting clay on the case shoulder and inserting it in his chamber is futile.

 

[lever-hed]

Woods, In that regard, I see the futility. This is main reason I neck size only, not only is it easier, it provides better quality ammo for a particular rifle, and don't have to mess with body sizing for the first few reloads. Happy hunting..

Boomtube, the RCBS mic is great tool IMHO, does the job and repeatable ,plain and simple. The collapsable tool works ok, except you have to make sure the tension is consistent each time get consistent results, I use that tool with the hornady bullet comparator to get the oal to lands(actual dimension). But guess a little heavier on the wallet compared to your method..

 

[boomtube]

"The collapsable tool works ok, except you have to make sure the tension is consistent each time get consistent results,...."

Agreed, that's why I gave up on it. I found it just to difficult to put the same pressure on the plunger and lock it in place without any movement. And I consider myself to have good manual dexterity!

I went back to my old ways for consistancy alone. I can do it ten times in a row and get virtually identical readings. So close, in fact I have given up bothering to do more than one test and averaging the results as I did before.

Cheers!

 

[overbore]

I use Competition shell holders to adjust headspace -as and when necessary. Overbore