The Firing Line Forums - View Single Post

Pond, James Pond · December 27, 2013, 04:54 PM

OAL. I know this has been covered before and I myself touched on it some months ago, but I really need to beat this drum tonight...

At the end of it, I'd like to know if I'm doin' it wrong, my kit is not up to task or it is actually not such a big deal.

Tomorrow I am off to the 100m range to try out my OCW loads and so tonight I made the finishing touches. When I first painstakingly measured up my OCW selection of loads and seated the bullets, I was still not sure what my distance to lands was in my chamber and so I seated the bullets way out in order to seat them to the desired OAL later. That being this evening. My chamber comes to 73mm or there abouts. That means that my OAL limiting factor is mag size, not chamber and my max OAL is 2.8" or 71.12mm. I opted for 71mm dead to avoid and feeding issues in the mag.

All the cases are neck-resized, trimmed Norma brass, and all have Hornady A-max .30 Cal 155gr bullets in them. So, I foolishly expected the OAL to be bang on the same for each case I put in the press, but after seating them all with my die set to 71.000000000mm, I found a max length of 71.12mm and a min of 70.85.

That is under a third of a millimeter, so part of me is thinking that this is no big deal. But then if I am trying to develop precise shooting loads, all parameters should be the same, so why the difference in OAL when all components are the same.

So is it me, the Lee, or no biggie?
Even if benign, why the difference?

December 27, 2013, 04:54 PM	#1
Pond, James Pond Senior Member Join Date: July 12, 2011 Location: Top of the Baltic stack Posts: 6,079	Is it me, or is it Lee? OAL. I know this has been covered before and I myself touched on it some months ago, but I really need to beat this drum tonight... At the end of it, I'd like to know if I'm doin' it wrong, my kit is not up to task or it is actually not such a big deal. Tomorrow I am off to the 100m range to try out my OCW loads and so tonight I made the finishing touches. When I first painstakingly measured up my OCW selection of loads and seated the bullets, I was still not sure what my distance to lands was in my chamber and so I seated the bullets way out in order to seat them to the desired OAL later. That being this evening. My chamber comes to 73mm or there abouts. That means that my OAL limiting factor is mag size, not chamber and my max OAL is 2.8" or 71.12mm. I opted for 71mm dead to avoid and feeding issues in the mag. All the cases are neck-resized, trimmed Norma brass, and all have Hornady A-max .30 Cal 155gr bullets in them. So, I foolishly expected the OAL to be bang on the same for each case I put in the press, but after seating them all with my die set to 71.000000000mm, I found a max length of 71.12mm and a min of 70.85. That is under a third of a millimeter, so part of me is thinking that this is no big deal. But then if I am trying to develop precise shooting loads, all parameters should be the same, so why the difference in OAL when all components are the same. So is it me, the Lee, or no biggie? Even if benign, why the difference? __________________ When the right to effective self-defence is denied, that right to self-defence which remains is essentially symbolic. Freedom: Please enjoy responsibly.