SES50
Well-Known Member
I started putting a new load together for my 300WM a while back to reach out a little farther than my old load and I fired it for the first time this week. The results are a little confusing. Maybe some of you can help me out.
When putting the load together I looked in three different books and interpolated between the 200 and the 220 loads to get the powder charge for the 210. This is what the books read:
1) Lee Modern Reloading Second Edition
200 Grain Jacketed Bullet
H1000 - Min 74.0 - 2723 FPS
Max 79.0c - 2883 FPS
220 Grain Jacketed Bullet
H1000 - Min 73.0 - 2597 FPS
Max 78.0 - 2750 FPS
So I get for 210 Grain Bullet 73.5 - 78.5 Grains of powder from this book.
2) Barnes Reloading Manual Number 3
200 Grain Bullet
H1000 - Min 72.5 Grains - 2516 FPS
Max 77.5 Grains - 2689 FPS
3) Speer Reloading Manual Number 13
200 Grain Bullet
H1000 - Min 73.0 Grains - 2629 FPS
Max 77.0c Grains - 2797 FPS
So I loaded up 5 rounds of each load between 76.0 - 78.5 in half grain intervals to see what I got. My crono did not read every round fired but I got some readings for every shot fired. Also all the brass showed high pressure signs with the primer pushed out flat and one case actually having the head pop off after it was back in my reloading bullet carrier box.
Here are the speeds I recorded:
78.5 Grains
2930
2936
2936
2962
2962
78.0 Grains
2962
NR
NR
NR
2898
77.5 Grains
NR
2917
2861
2892
2892
77.0 Grains
2861
2879
2873
2867
2886
76.5 Grains
2930
2949
2982
2976
2996
76.0 Grains
NR
2949
NR
2917
2969
So the interesting thing is that the velocities start high then drop down as the powder goes down in volume and then the velocities increase again. I am shooting these out of a 26" barrel on a T/C Encore and the velocities seem really high with what I compare to the velocities the book says I should be getting. If I figure every inch of extra barrel adds about 50 FPS these bullets should not be going this fast.
These loads are not crimped and are .010" off the lands. I am using GM215M primers and I trickled every powder load so I believe the powder weight is dead on. Also the 78.5 Grain load had the best group at a little over .5 MOA.
So, can anyone explain to me why I am getting the cases falling apart and the primers really pushed out? And why do I have the strange velocity fluctuations? Anyone else using H1000 in a 300WM?
Thanks
SES
When putting the load together I looked in three different books and interpolated between the 200 and the 220 loads to get the powder charge for the 210. This is what the books read:
1) Lee Modern Reloading Second Edition
200 Grain Jacketed Bullet
H1000 - Min 74.0 - 2723 FPS
Max 79.0c - 2883 FPS
220 Grain Jacketed Bullet
H1000 - Min 73.0 - 2597 FPS
Max 78.0 - 2750 FPS
So I get for 210 Grain Bullet 73.5 - 78.5 Grains of powder from this book.
2) Barnes Reloading Manual Number 3
200 Grain Bullet
H1000 - Min 72.5 Grains - 2516 FPS
Max 77.5 Grains - 2689 FPS
3) Speer Reloading Manual Number 13
200 Grain Bullet
H1000 - Min 73.0 Grains - 2629 FPS
Max 77.0c Grains - 2797 FPS
So I loaded up 5 rounds of each load between 76.0 - 78.5 in half grain intervals to see what I got. My crono did not read every round fired but I got some readings for every shot fired. Also all the brass showed high pressure signs with the primer pushed out flat and one case actually having the head pop off after it was back in my reloading bullet carrier box.
Here are the speeds I recorded:
78.5 Grains
2930
2936
2936
2962
2962
78.0 Grains
2962
NR
NR
NR
2898
77.5 Grains
NR
2917
2861
2892
2892
77.0 Grains
2861
2879
2873
2867
2886
76.5 Grains
2930
2949
2982
2976
2996
76.0 Grains
NR
2949
NR
2917
2969
So the interesting thing is that the velocities start high then drop down as the powder goes down in volume and then the velocities increase again. I am shooting these out of a 26" barrel on a T/C Encore and the velocities seem really high with what I compare to the velocities the book says I should be getting. If I figure every inch of extra barrel adds about 50 FPS these bullets should not be going this fast.
These loads are not crimped and are .010" off the lands. I am using GM215M primers and I trickled every powder load so I believe the powder weight is dead on. Also the 78.5 Grain load had the best group at a little over .5 MOA.
So, can anyone explain to me why I am getting the cases falling apart and the primers really pushed out? And why do I have the strange velocity fluctuations? Anyone else using H1000 in a 300WM?
Thanks
SES