Overpressure DPMS .308? ***Update***

Problem solved! So I went through and sized what I had left for fired brass. First annealed it, then I went through and sized it just enough until it would chamber and eject fine. I then loaded various charges from 41 to 45 grains of Varget. Not a single overpressure sign! So I was sizing too much.

I should also note that as I stepped up in charge my groups shrank. My worst group was 1.22" (only group over 1") and my best ended up at .662". Much more consistent than my last batch. These were only three round groups, so I'm sure they would open up a bit with five round s instead of three. At $37 a box, it gets expensive in a hurry doing load development.
 
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Originally Posted By: jasonprox700Problem solved! So I went through and sized what I had left for fired brass. First annealed it, then I went through and sized it just enough until it would chamber and eject fine. I then loaded various charges from 41 to 45 grains of Varget. Not a single overpressure sign! So I was sizing too much.

I should also note that as I stepped up in charge my groups shrank. My worst group was 1.22" (only group over 1") and my best ended up at .662". Much more consistent than my last batch. These were only three round groups, so I'm sure they would open up a bit with five round s instead of three. At $37 a box, it gets expensive in a hurry doing load development.

Glad your problem is solved, Jason. Thought that would take care of it.

As for cost of load development, you can cut some corners and save a lot of $$$$ using Creighton Audette's Ladder method of load development described here:

http://precisionrifleblog.com/2012/07/13/creighton-audette-ladder-testing/

By loading 8-15 rounds, starting at low end of loading book suggested charge and stepping up .2 (for small capacity cases) or .3 gr. (for your .308) of powder in each succeeding round (stopping somewhere below max. load shown) and carefully monitoring cases for pressure signs, you can determine safe pressure range in your rifle and also identify the accurate nodes as they might appear on the target and indicated by velocities shown on your chronograph. Pick the center load indicated in each node and load 5 rounds. You may find more than one node in any given ladder and I like to explore all of these. This usually results in an accurate load w/less rounds expended.

It is also not uncommon to identify loads that can vary as much as .5 gr. (+/- .25 gr.) without affecting accuracy, making it practical to throw charges rather than the more tedious method of weighing every charge.

Give it a try, I think you'll like it.

Regards,
hm
 
I just read the article you linked. When I get a little more time I'm going to try this out on a couple of my other calibers and see how it goes. I really like the idea and think it will work.
 
How can a person resize to much if you follow the directions of the full length die set up ? A am asking because this is the first I read about it only been reloading for 5 years.
 
Originally Posted By: JeepyjerHow can a person resize to much if you follow the directions of the full length die set up ? A am asking because this is the first I read about it only been reloading for 5 years.

The instructions are set for the masses. They give a starting point. Every gun is slightly different because the tools they use to cut and ream are constantly wearing. Depending on the conditions your gun was made, it might of been the first action/barrel or the last for a set of tools. What this means to you is that your chamber could be really tight (barely meets sami specs) or is horribly sloppy, but barely meets sami spec at the top end.

The dies are set for middle of the road, you have to read your brass for signs of what is going on. The headspace gauges are nice for references, but you still have to figure out how to read them for your specific gun.

While it is not the recommended way, i backed my die off till a case would not chamber and then i started turning it back in a tiny bit and retested. After i found what would chamber, i turned it a tiny bit more and then i considered the die set. That die just loaded its 5000th round and i have yet to have a round that would not chamber. I do not recommend you to do this with a AR. I do not use this method any longer.

I now use headspace gauges a lot. Headspace is very important, even more so if you trim off the shoulder (giraud, wft, etc)
 
Originally Posted By: captninsano
While it is not the recommended way, i backed my die off till a case would not chamber and then i started turning it back in a tiny bit and retested. After i found what would chamber, i turned it a tiny bit more and then i considered the die set.

Commonly known as *partial sizing*.

Lots of guys do it this way.
 
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