Long Range Hunting Online Magazine


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

Reloading Techniques For Reloading


Reply

300RUM problems

 
LinkBack Thread Tools Display Modes
  #1  
Old 04-30-2009, 07:35 AM
Bronze Member
 
Join Date: Dec 2004
Location: South Africa
Posts: 40
300RUM problems

I've been picking up some strange problems with my 300RUM reloads. would appreciate any help. Here are the details:
Foster CO-Ax press
Foster dies (FL sizing die)
Rem brass (twice fired)
220gr SMK bullet
CCI mag primer
Local powder (South African)

I've sorted the cases by uniform case thickness and weight. All cases have been trimmed to uniform thickness, just below max length.

Problem:
The case won't chamber 100%. The case slides forward into the chamber until it seems that the shoulder of the case or neck enters the neck / shoulder part of the chambering then there's trouble. This never happens with new unfired cases.

It seems to me that there is a doughnut effect at the junction between the case body and shoulder. This does not happen with every case, probably 1 in 5 cases. Sometimes this doughnut is not visible to the eye. (it is also quite possible the this may not be the problem and that I'm missing something else).

Can anybody shed some light oin what's happening ? Is it possible on seating the bullet that the bullet is pushing down on the neck thus deforming the shoulder ?
Reply With Quote
  #2  
Old 04-30-2009, 08:07 AM
Platinum Member
 
Join Date: Oct 2005
Location: Michigan
Posts: 2,232
Re: 300RUM problems

Quote:
Originally Posted by pvanwyk View Post
I've been picking up some strange problems with my 300RUM reloads. would appreciate any help. Here are the details:
Foster CO-Ax press
Foster dies (FL sizing die)
Rem brass (twice fired)
220gr SMK bullet
CCI mag primer
Local powder (South African)

I've sorted the cases by uniform case thickness and weight. All cases have been trimmed to uniform thickness, just below max length.

Problem:
The case won't chamber 100%. The case slides forward into the chamber until it seems that the shoulder of the case or neck enters the neck / shoulder part of the chambering then there's trouble. This never happens with new unfired cases.

It seems to me that there is a doughnut effect at the junction between the case body and shoulder. This does not happen with every case, probably 1 in 5 cases. Sometimes this doughnut is not visible to the eye. (it is also quite possible the this may not be the problem and that I'm missing something else).

Can anybody shed some light oin what's happening ? Is it possible on seating the bullet that the bullet is pushing down on the neck thus deforming the shoulder ?

Probably your problem, unless your sizing die is dirty and doing the same thing. Is it a new die? Did you clean it? What kind of lube are you using? Do they ALL chamber before seating a bullet? Do you have a sizing ball on the decapping pin?


AJ
__________________
If some is good and more is better, then too much is just right.


My mind is a raging torrent, flooded with rivulets of thought, cascading into a waterfall of creative alternatives
Reply With Quote
  #3  
Old 04-30-2009, 08:12 AM
Gold Member
 
Join Date: Jun 2006
Location: Shangri-La
Posts: 931
Re: 300RUM problems

A couple of questions:

You said the do-nut is at the junction of the case body and shoulder. Normally a do-nut is on the inside of the case and is at the junction of the shoulder and neck


and obstructs the passage of a bullet below that point on a fired case. Is this the do-nut you are talking about? If not, can you post a pic? I'd like to see one at the case body/shoulder junction.

Second question would be how are you setting up your dies? i.e. are you threading them in till they hit the shell holder, a little further or a little less?
__________________
If you can read this, thank a teacher.......if you are reading this in English, thank a soldier.
Reply With Quote
  #4  
Old 04-30-2009, 09:26 AM
Bronze Member
 
Join Date: Dec 2004
Location: South Africa
Posts: 40
Re: 300RUM problems

thanks for the replies. The "doughnut" is between the shoulder and case body on the outside (from what I have seen) and not in the traditional sense when neck trimming. Will post a pic later. (have not cut the necks)

the setup of the dies is a good point. I have recently got a gauge to measure the set back of the shoulder but have not yet loaded ammo with the gauge. I had previously setup the dies by screwing in the body to the shell plate and then a touch further in.

Will check if the die is dirty but that wouldn't expalin that only 1 in about every 5 is giving a problem. using Imperial sizing wax (?) and do have the sizing ball in.
Reply With Quote
  #5  
Old 04-30-2009, 09:33 AM
Silver Member
 
Join Date: Jan 2007
Posts: 184
Re: 300RUM problems

If your seating die is adjusted too deep into the press (bottom of the die bumps the shell holder or is too close to it), you may be accidently crimping the case mouth just a bit. If so, this "can" cause a slight bulge outward of the case right at the point where the neck begins to taper outward to become the shoulder.

Could be something else, but this is worth a look.

Jim
Reply With Quote
  #6  
Old 04-30-2009, 09:49 AM
Platinum Member
 
Join Date: Dec 2002
Location: Northern Michigan
Posts: 1,014
Re: 300RUM problems

Double check to make sure you don't have the expander ball adjusted to high. The bottom of the expander ball should be closely in line with the hole in the side of the die (per directions).

Try taking the expander out and size, see if you get the same problem.
Reply With Quote
  #7  
Old 04-30-2009, 10:38 AM
Platinum Member
 
Join Date: Jun 2007
Location: Wilmington NC
Posts: 4,227
Re: 300RUM problems

Quote:
Originally Posted by pvanwyk View Post
the setup of the dies is a good point. I have recently got a gauge to measure the set back of the shoulder but have not yet loaded ammo with the gauge. I had previously setup the dies by screwing in the body to the shell plate and then a touch further in.
My guess is you are sizing the shoulder down too far and creating a small microscopic ridge that you are seeing as the donut. Had this happen to me once. Mftr directions are designed to be lawyer proof and not conducive the max accuracy.

Back the die off 1/8 inch and start back down sizing until they will just chamber. Also use a bump guage to measure, virgin, once fired and 3x fired. Normally by 3x, the brass has flowed to chamber dimensions.

BH
Reply With Quote
Reply

Bookmarks

Thread Tools
Display Modes


Similar Threads for: 300RUM problems
Thread Thread Starter Forum Replies Last Post
700 problems michaln Gunsmithing 16 11-16-2009 09:09 AM
270/300RUM problems any ideas? eddybo Rifles, Bullets, Barrels & Ballistics 0 11-17-2008 11:10 AM
300rum RELOADING Brass PROBLEMS!!!! 300rum Reloading 6 08-14-2006 09:49 AM
Help! 300RUM load problems RDM416 Reloading 6 07-14-2005 12:32 PM
6.5 x 284 SD problems Varmint Hunter Rifles, Bullets, Barrels & Ballistics 10 05-03-2005 08:31 AM


All times are GMT -5. The time now is 11:10 PM.


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