Thread: Some thoughts on 6.5 PRC

Interesting read. Some of the mentioned loads that have "no signs of pressure" show to be well over pressure when run through GRT. To be fair though GRT isnt always 100% accurate, usually a good indication though, i have found it to line up pretty close with my own real world results when all the right data is entered.

Not sure if i have just had 2 slow PRCs, or most people arent scared of just sending it with some strong brass & are running higher pressures than they think.

Originally Posted by 6.5 CRD

Interesting read. Some of the mentioned loads that have "no signs of pressure" show to be well over pressure when run through GRT. To be fair though GRT isnt always 100% accurate, usually a good indication though, i have found it to line up pretty close with my own real world results when all the right data is entered.

Not sure if i have just had 2 slow PRCs, or most people arent scared of just sending it with some strong brass & are running higher pressures than they think.

The most reliable "sign of pressure" is velocity, people get hung up about looking for flattened primers, heavy bolt lift or ejector stamping etc but just because you can't see it doesn't mean it isn't there (a bit like the wind) assuming all other things are equal if loading to saami spec then velocity is a fairly accurate sign of pressure. Obviously if you are seating longer or shorter that is where tools like GRT are good as a guideline, there are other variables like case volume and hardness etc. There will always be exceptions to this however I would suggest if your getting velocity that is well above book max charges there are no free lunches it isn't a magic powder or rifle chamber that is some how immune to pressure, you will end up trashing brass or eroding your barrel quicker or both or in extreme cases a failure of some sort.
Not preaching to the O.P just my 2 cents.

This of course has been said before but it never hurts to repeat it

Originally Posted by dannyb

The most reliable "sign of pressure" is velocity, people get hung up about looking for flattened primers, heavy bolt lift or ejector stamping etc but just because you can't see it doesn't mean it isn't there (a bit like the wind) assuming all other things are equal if loading to saami spec then velocity is a fairly accurate sign of pressure. Obviously if you are seating longer or shorter that is where tools like GRT are good as a guideline, there are other variables like case volume and hardness etc. There will always be exceptions to this however I would suggest if your getting velocity that is well above book max charges there are no free lunches it isn't a magic powder or rifle chamber that is some how immune to pressure, you will end up trashing brass or eroding your barrel quicker or both or in extreme cases a failure of some sort.
Not preaching to the O.P just my 2 cents.

This of course has been said before but it never hurts to repeat it

I have always respected book max but also would run a ladder, must increments of .3 of a grain would produce say 20-30 fps increase. When you get a sharp increase in velocity you are normally at pressure.
That is why you should start low and work up, every rifle is different and pressure/velocity will not be the same.
Thats why some rifles are faster than others, just because Joe Blogs rifle does 3000 fps does not mean a different rifle will be.