Runout in a reamer design.

[Changeling]

Guys, I am contemplating having a reamer built but there some things I am unsure about,base cartridge is 6BR).

The term "Run out", how does it apply to the design of the reamer and how is it executed correctly.
Changeling

 

[mikecr]

Missed that one somewhere. I've designed 4 reamers now & haven't seen or heard of run out as a desired parameter. And Kiff never mentioned it.
Are you talking about chamber runout, as caused by reaming without first boring?

 

[Changeling]

Hi Mike. I don't think so, still unsure. I have also had several reamers built and never questioned this, didn't know I should really!
See bench rest central, I proposed the question in a little more depth there.

 

[Changeling]

Hi Mike. I don't think so, still unsure. I have also had several reamers built and never questioned this, didn't know I should really!
See bench rest central, I proposed the question in a little more depth there.

Mike, first off thanks for replying and making this a topic that I have interest in!!
It appears that most people are not to enthused about my ideas. however I don't let those type of things bother me much. The guys over there have given some great advise and things to think about!
However, after giving it some thought on my own I think that it involves the changing of the basic cases body taper and it's relevancy to the eventual fired case. This would also include the shoulder angle/case length.
One of the major problems now is the discrepancy in case capacities reported from various 6BR cartridges, namely Standard and modified.
Standard 6BR and modified 6BR capacities seem to vary a lot depending on who you are talking to. I sincerely believe this is a direct reflection on the reamers/maker and how they are used to make a chamber. There are a hell of a lot of modified chambers that call them selves "6BR Dasher", probably the same for all variation/names that don't produce consistent results within some logical degree, I also include the "Standard Reamer" in this scenario on it's on capacities.
There is of course some variation due to reamer usage,# chambers cut)
Then we come to shoulder angles, but that is another story!
Changeling

 

[mikecr]

All true, and this is why I always buy my own reamers. I get to choose the specs, and know exactly what they will be for all barrels done.
If your interested in my 6Dasher, I could send you a reamer print scan, and drawing of what a fired case should measure from my chamber. Hell, your welcome to use my reamer if you decide it would work for you. I normally specify a coaxial throat, ~.0005 over cal, and enough freebore for the heaviest Secant bullet range.

 

[Changeling]

Mike that is an extremely kind offer. Check your mail.
Changeling