Long Range Hunting Online Magazine


Go Back   Long Range Hunting Online Magazine > Rifles, Reloading, Optics, Equipment > Reloading

Reloading Techniques For Reloading


Reply

Bearing Surface Length Measurement Question

 
LinkBack Thread Tools Display Modes
  #8  
Old 12-15-2006, 07:08 PM
Platinum Member
 
Join Date: Aug 2003
Location: NC, oceanfront
Posts: 3,296
Re: Bearing Surface Length Measurement Question

This is the best I've used:
http://www.davidtubb.com/tcom_images...g/bsc_one.html

The Sinclair thingy is handy as heck for OAL/seating depth checks, but won't help with bearing surface measurements. Nor will the Stoney point rigs(which I hate).

Bearing surface doesn't start anywhere near bore diameter. It starts at caliber, both at the nose and boat tail.
Reply With Quote
  #9  
Old 12-15-2006, 07:37 PM
Platinum Member
 
Join Date: Feb 2004
Location: Pennsyltucky
Posts: 2,625
Re: Bearing Surface Length Measurement Question

Mike, we understand that the ogive starts at complete bullet dia. the question was what dia hole should be used to check bearing surface length.most use something around the bore dia. for this operation. if you read the info on the one you like, it also uses bushings with holes that are "bore diameter"

Roy, i'd like to post some pixs of my project as there are several that would like to see it. my problem with this is i can't get my computer enlightened stepsons over hear to take pictures and of course, post them for me.i also have heard from many that i have fractional brain loss except they usually use a fraction that is much greater than 1/2! hoping to get-r-done this weekend.
__________________
davesonlinedeals.com
Reply With Quote
  #10  
Old 12-15-2006, 07:57 PM
Platinum Member
 
Join Date: Jun 2007
Location: Wilmington NC
Posts: 4,172
Re: Bearing Surface Length Measurement Question

The Buhay Ogive checker is the top of the line. It looks exactly like the Tubbs because John Buhay makes it and sells it to David. It is also sold thru RW Hart and sons in PA for $125. It is more accurate than the stoney points due to variance in pressure for most people. If you are a machinest and have calibrated hands the stoney points work well.

BH
Reply With Quote
  #11  
Old 12-15-2006, 08:37 PM
Platinum Member
 
Join Date: Jan 2004
Location: Blackfoot, Idaho
Posts: 8,117
Re: Bearing Surface Length Measurement Question

[ QUOTE ]
Bearing surface doesn't start anywhere near bore diameter. It starts at caliber, both at the nose and boat tail.

[/ QUOTE ]

Now I'm really confused. I drill my holes @ 0.277 and 0.338 and guess what? Just as common sense (which I am a bit short on these days [img]/ubbthreads/images/graemlins/blush.gif[/img]) would indicate the bullets very precisely slid through. At that moment the ol' noggin kicked in. Thus the above question.

My objective would be to measure Base to Ogive (or whatever that standard diameter ends up being) and sending the round to say Dave, for example, and he measures the same within reason.

Further, when I "cram" a seated bullet into the rifling to determine max length, and am lucky enough to not have the bullet stick in the barrel or be too loose in the neck and slide a bit, on factory rifles the bullet is marked with rifling marks. I back off on the seating die until there are no marks and define that length as COL.
__________________
I may be the slowest guy on the mountain . . . . but . . . . I'm on the mountain!
Reply With Quote
  #12  
Old 12-15-2006, 09:57 PM
Platinum Member
 
Join Date: Sep 2004
Location: on the rifle range in Utah
Posts: 2,723
Re: Bearing Surface Length Measurement Question

[ QUOTE ]
The Sinclair thingy is handy as heck for OAL/seating depth checks, but won't help with bearing surface measurements. Nor will the Stoney point rigs(which I hate).


[/ QUOTE ]

Yes they will. Two Stoney Points measure the same thing the Tubb's do. And in fact, when measuring several hundred 300 grain MK's with both the Tubb's and the Stoney POints, all but just a very few measured into the same piles of segregation. The ones that differed were only a .001 or two. Tubb's is certainly more refined, but either method accomplishes the job just as well. Constant pressure on the SP is fairly easy to attain with some practice.
__________________
Find it
Range it
Click it
Pull it
Dump it

If it's not far, it's boring.
Reply With Quote
  #13  
Old 12-16-2006, 09:45 AM
Platinum Member
 
Join Date: Nov 2003
Location: Washington State
Posts: 2,462
Re: Bearing Surface Length Measurement Question

Roy, I hope I didn't steer you wrong with the Sinclair Comparator. I looked at your picture and saw what you were measuring and thought 'why not the Sinclair gizmo'? But, it look like you are trying to measure bearing surface, which the Sinclair Bullet Comparator isn't specifically designed for.
__________________
In the beginning God created the heavens and the earth. Genesis 1:1

"And can the liberties of a nation be thought secure when we have removed their only firm basis, a conviction in the minds of the people that these liberties are the gift of God?" Thomas Jefferson - Notes on the State of Virginia

www.wildsidesystems.com - Shelter for Your WildSide - http://www.youtube.com/watch?v=tYwgo...&feature=g-upl
Reply With Quote
  #14  
Old 12-16-2006, 11:46 AM
Platinum Member
 
Join Date: Feb 2004
Location: Pennsyltucky
Posts: 2,625
Re: Bearing Surface Length Measurement Question

Roy, i gave you the hole sizes you need to drill?

these comparators don't actually give you the bearing surface length. they simply give you a method of segregating bullets so they all have similar bearing surface length.
__________________
davesonlinedeals.com
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes


Similar Threads for: Bearing Surface Length Measurement Question
Thread Thread Starter Forum Replies Last Post
Bullet Bearing Surface Length Question(s) royinidaho Rifles, Bullets, Barrels and Ballistics 18 07-07-2013 08:07 AM
Bearing surface length? txsendero Rifles, Bullets, Barrels and Ballistics 3 12-23-2009 06:58 PM
Bullet bearing surface question jmason Reloading 11 10-07-2008 05:09 PM
Bearing Surface Length Consistency and How anal to get? royinidaho Rifles, Bullets, Barrels and Ballistics 1 10-16-2005 01:15 PM
Sorting bullets: Base to ogive vs length of bearing surface. BountyHunter Rifles, Bullets, Barrels and Ballistics 5 08-06-2003 10:55 AM


All times are GMT -5. The time now is 02:09 AM.


Powered by vBulletin ©2000 - 2014, Jelsoft Enterprises Ltd.
Content Management Powered by vBadvanced CMPS
All content ©2010-2014 Long Range Hunting, LLC