Determining seating depth

[BOB LEE SWAGGER]

Is it possible to determine "0" freebore to start the process of finding optimal jump or jam by using a reamer print? I have a Hornady & Sinclair bullet seating depth gauge and still would like to know! I will be using 105 vld's & hybrids for my dasher. Thanks.

 

[dmoran]

Besides the listed tolerance's on reamer prints, there can be more error from what the prints say to what the actual reamers measure. With that said, and in my opinion, they can work for "guess-to-mating", but will not be factual. We still have to measure with the intended bullets were going to use....... rats !.!.!
Donovan

 

[DeadEyeDick45]

Maybe this video will help.
https://www.youtube.com/watch?v=3lppK2jJ3XE

 

['Freak]

If talented enuf so in the utilization of somebody like AutoCAD and if you could put together very detailed, very accurate renderings of the projectile and the chamber region of barreled action with the projectile as part of a loaded round seated inside the chamber, then you could probably get it down to something fairly close. Be a lot easier, quicker, cheaper, and you'll get more accurate numbers doing it all real world.

 

[Lapua40X]

If you truly want to take the guess work out of it, this is the way to go IMO.
http://www.midwayusa.com/product/462291/cerrosafe-chamber-casting-alloy-1-2-lb

 

[BOB LEE SWAGGER]

Thanks to all.

 

[Ackman]

Is it possible to determine "0" freebore to start the process of finding optimal jump or jam by using a reamer print? I have a Hornady & Sinclair bullet seating depth gauge and still would like to know! I will be using 105 vld's & hybrids for my dasher. Thanks.

To find seating depth with the bullet touching lands, a reamer print won't help you and a chamber cast will be useless. You've gotta actually seat a bullet and measure casehead to ogive length. Easiest cheapest simplest quickest tool is a split neck case. But some people like to complicate things.

 

[Joe R]

dmoran
Besides the listed tolerance's on reamer prints, there can be more error from what the prints say to what the actual reamers measure. With that said, and in my opinion, they can work for "guess-to-mating", but will not be factual. We still have measure with the intended bullets where going to use.... rats !.!.!
Donovan

I'm with Donovan. It's like sex, just do it and you'll know. Don't waste your time masturbating with Autocad and prints.

Joe

 

[Richard Jones]

......... Easiest cheapest simplest quickest tool is a split neck case.........

And more precise than a Hornady-ish type tool, at least for me. Mine, a smith-made custom job, gathers dust.....

 

[Corey Schwanz]

I would just measure in the actual chamber so you know for sure what the depth to the lands is. A reamer print may get you close but specs and real thing sometimes don't match up perfectly.

 

[djtjr]

Sinclair or hornady tool takes 5 minutes take the average of 3 attempts gets you within .001 or.002 of the lands every time

 

[CaptainMal]

Trick I learned to get the Hornady gauge to repeat is pushing the bullet into the barrel until it sticks. If you bring the case out and the bullet is in the case my experience says the reading will not be correct.

Stick and push the bullet out repeats the measurement easily for me.