03-26-2020, 03:00 PM
Like has been said above 41 years ago when I started hand loading chronograph's were cost prohibitive to own. But also the load data that was put out was also MUCH heaver on the powder than most today. I have and old Speer manual that the max loads are scary and some like in 30-06 you would have trouble getting that much powder into a case. That is where the "watching for pressure signs" came from. We had no idea of what velocity we were getting but we could see if primers were flattening and we could see if a case head was growing and we could feel in bolt and leaver actions if action was stiff on ejection. We could feel when sizing the case if it was hard to do pressure was too high. We could feel when seating a new primer if the pocket was loose and know pressure was too high on previous load. I also have some wildcats and had to use these things to work up loads for them.
Today loading data is pretty conservative compared to many of my loads in some weapons but then there are some like my custom 264 Win mag which has a chamber on the tight side that I can't get within a about 2 grs. of a max load without running into pressure but having a chronograph now I can see that I am getting the velocity that data says I would get with 2 more grains of that powder. So it is load to what YOUR weapon wants to digest.
My load of IMR 8208 is quite a bit more for the Speer 120 Gold Dot than Speer's data list and my velocity is a bit more than what their max load states they got. But when I load their max load and even taking into account the velocity loss of my 20" barrel compared to their 24" barrel I was WAY low on velocity. One thing I have learned over the years is that when doing a load work up you will usually find a load, node these days, for great accuracy before you run into high pressure. If you are going to be using your 6.5 Grendel for hunting and will not be shooting over 300ish yards the game will not know if the bullet was running 2600 fps or 2400 fps. Accuracy kills.
Today loading data is pretty conservative compared to many of my loads in some weapons but then there are some like my custom 264 Win mag which has a chamber on the tight side that I can't get within a about 2 grs. of a max load without running into pressure but having a chronograph now I can see that I am getting the velocity that data says I would get with 2 more grains of that powder. So it is load to what YOUR weapon wants to digest.
My load of IMR 8208 is quite a bit more for the Speer 120 Gold Dot than Speer's data list and my velocity is a bit more than what their max load states they got. But when I load their max load and even taking into account the velocity loss of my 20" barrel compared to their 24" barrel I was WAY low on velocity. One thing I have learned over the years is that when doing a load work up you will usually find a load, node these days, for great accuracy before you run into high pressure. If you are going to be using your 6.5 Grendel for hunting and will not be shooting over 300ish yards the game will not know if the bullet was running 2600 fps or 2400 fps. Accuracy kills.