adjusting your seating depth

[mattkarstetter]

I am looking for info on how you guys adjust your seating depth to optimize accuracy once you have found a preatty accuratly load.

how far are your changes in oal between different test loads for fine tuning

im not very close to the lands on my factory rem 308 when i reach magazine length, so i curious if there is a big benefit to be had by adjusting in .001 increments.

any thoughts.

thanks in advance

 

[918v]

Re: adjusting your seating depth

I adjust in .010" increments. Bullets vary much more than .001" to yield a significant change from that degree of adjustment.

 

[bohem]

Re: adjusting your seating depth

If you read Berger's loading instructions they give a good method for narrowing down the seating depth for a new VLD load length. I've found it works just as well for narrowing down the seating depth with nonVLD bullets as well.

Just an FYI, I have yet to find a better COL with AMAX bullets beyond keeping them 10-15 thousandths off the lands. Seems to work for 5 of the 6 different calibers I've run it in. I haven't run a test on that 6th caliber yet, the ammo is sitting on my bench still.

 

[Victor N TN]

Re: adjusting your seating depth

In all honesty, with a factory barrel & chamber, you may not be able to get it out long enough to really do you any good. And most that do make it won't feed from the magazine.

Not to bring you down. Just to let you know the reality of things.

Good luck.

 

[BLAWTON]

Re: adjusting your seating depth

Vic is right. If you want to get close to the lands you mag be well past mag length. You would have to keep the loads seperate and just single feed them if you are planning on taking some long shoots that needs that extra accuracy...

When i do my seating depth adjustment i start right on the lands and then back off .005 at a time until you get to .035 off. If its not working somewhere in their then try .01 to .02 in and more then .08 off.

 

[308sako]

Re: adjusting your seating depth

Deleted in protest!

 

[dmgreene]

Re: adjusting your seating depth

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: bohem</div><div class="ubbcode-body">

Just an FYI, I have yet to find a better COL with AMAX bullets beyond keeping them 10-15 thousandths off the lands. Seems to work for 5 of the 6 different calibers I've run it in. I haven't run a test on that 6th caliber yet, the ammo is sitting on my bench still. </div></div>

I have had the same results with AMAX bullets. Every time I have tried to seat them in the lands the accuracy starts to go the other direction. .010" off the lands is usually where I end up.

 

[carlton]

Re: adjusting your seating depth

I started with the Berger test noted above, and got some great procedure tips and really good results at .080 off the lands in my DPMS. 6.5 CM (Berger 140 VLD Hunting, and I started at max magazine COLA, and worked back. I first wanted to make up some hunting loads with the 140VLD Hunting that were mag-friendly. My next test will be with rounds on the jam, and just single feed. I ended up at .026" off lands with my 140 Amax, it was good so I stopped there.
Long story short, I use this exact process for about everything now