Long Range Hunting Online Magazine


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

Reloading Techniques For Reloading


Reply

How accurate should COL be?

 
LinkBack Thread Tools Display Modes
  #1  
Old 10-13-2011, 01:21 PM
Junior Member
 
Join Date: Oct 2010
Location: Southern Oregon
Posts: 28
How accurate should COL be?

I've been having an annoying problem where I can't seem to get my die to consistently seat bullets to the same depth. These are being measured at the ogive with a comparator.

If it matters, most of the brass is reused federal and the bullets are SMK HPBT 175's. Hornady dies, RCBS press.

The closest accuracy I can seem to get with depth is +/-.01. I'll get some that are really close, within .001 and then all of a sudden one will be .005 too short. Then the next one might be long. It's maddening.

Competition dies are supposedly adjustable to .001 so is this kind of variance normal with regular dies? And would a competition die really fix the problem?

At the end of the day, am I really going to see the difference on paper?
Reply With Quote
  #2  
Old 10-13-2011, 02:55 PM
Platinum Member
 
Join Date: Feb 2009
Location: Sedalia, MO
Posts: 1,253
Re: How accurate should COL be?

Siegrisj,

The dies are adjustable, and I'll bet you that they aren't varying a bit. The bullets are another matter. From what you've described, I'd say the ogives are varying on you, and that's what's showing up when you measure them. Remember, the seating plug hits the ogive far closer to the meplat than the major diameter where your gage is checking the ogive. Whatever variation there is in the bullets, is probably what you're seeing when you take the measurments. I'd suggest trying Bergers or (dare I say) Lapuas and see if that doesn't drastically reduce these measurments. Not all manufacturers pay as close attention as they should to base/ogive variation.
__________________
Kevin Thomas
Lapua USA
Reply With Quote
  #3  
Old 10-13-2011, 03:25 PM
Junior Member
 
Join Date: Oct 2010
Location: Southern Oregon
Posts: 28
Re: How accurate should COL be?

Kevin,
Thanks for the response. So if I am following your logic correctly, I should be able to measure a sample of bullets at their ogives and see the same kind of variation with just bullets themselves right?

I might have to take you up on trying something different, although I thought Sierra's were supposed to be the bullet by which all others are judged. Which I guess translates into some will be better and some will be worse.

Thanks
Reply With Quote
  #4  
Old 10-13-2011, 04:00 PM
Platinum Member
 
Join Date: Aug 2003
Location: NC, oceanfront
Posts: 3,331
Re: How accurate should COL be?

Kevin hit on a good one & it could be other things, or a combination of them.
It could be the press, an issue with the die setting or seater plug, greatly varying seating force, or an issue with measurement.
Describe each condition & let's rule these out.
Reply With Quote
  #5  
Old 10-13-2011, 04:11 PM
Platinum Member
 
Join Date: Feb 2009
Location: Sedalia, MO
Posts: 1,253
Re: How accurate should COL be?

Lots fo things involved here, but most of them can be overcome by consistent operation of the press. If the dies are properly locked and not moving within the press, the seating stem is tight and not moving, then this part of the system won't be an issue. I have seen many presses with enough slop or play in the linkage system that it would effect uniform seating, bu this could usually be eliminated by exerting a little lateral pressure on the handle when you seat. That is, pushing the handle consistely to the left or right while operating it through its stroke. That said, I'll still put my money on the bullets themselves as being the most likely culprits here. As I said, not everyone puts the same degree of care into base/ogive consistency as they should. Worth trying some others, just to see if this reduces or even eliminates the variation.
__________________
Kevin Thomas
Lapua USA
Reply With Quote
  #6  
Old 10-13-2011, 04:14 PM
Junior Member
 
Join Date: Oct 2010
Location: Southern Oregon
Posts: 28
Re: How accurate should COL be?

The press can't entirely be ruled out cause I have it set up in a ghetto fashion where it isn't firmly bolted to the desk. If the press isn't 100% firmly bolted, isn't that still a separate system from what happens internally in the press?

That seems to be an obvious thing to clean up and has been on my list for awhile.
Reply With Quote
  #7  
Old 10-13-2011, 04:16 PM
Platinum Member
 
Join Date: Feb 2009
Location: Sedalia, MO
Posts: 1,253
Re: How accurate should COL be?

Shouldn't be an issue, but it certaily will make it more difficult to operate. Bolt that sucker down, tight!
__________________
Kevin Thomas
Lapua USA
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes


Similar Threads for: How accurate should COL be?
Thread Thread Starter Forum Replies Last Post
Most Accurate AR -15 Capt Academy AR15/10 Rifles 62 06-29-2014 09:13 PM
Least accurate gun Mr.Moa Long Range Hunting & Shooting 46 05-29-2011 10:54 PM
accurate tommyc279 Muzzleloader Hunting 8 09-27-2009 08:35 PM
What is accurate? mikekelly Long Range Scopes and Other Optics 15 01-22-2006 11:58 PM
Just how accurate do I need to be? Iron Worker Reloading 12 11-15-2005 02:31 PM


All times are GMT -5. The time now is 11:48 AM.


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