Les in Wyoming
Well-Known Member
I went through a lot of headache developing my 300 wm load. I could not get Bergers to shoot as accurate as Hornady ELD-m. My load is a 208 gr eld-m with 77.5 H-1000 and .090 jump. Hope this helps as a reference.
In your vertical/ latter test keep the bullets the same off the lands. So say .015 off the lands. Then load some up with your powder as such. 71 - 71.5 - 72 - 72.5 - 73 - 73.5 and so on. Go up 1/2 grain increments. I like to go back to 300 yards while doing this. After each shot mark the bullet impact so you don't get confused on what powder charge was used. Pick the ones that are closest together. After you decide the one you want then start messing with the seating depth.Hi All,
So I have a Bergara Premier Highlander in .300 Win Mag that I am working on some hand loads for. I am using Berger 215's, H1000, Norma Brass, CCI 250's, and Redding Type-S Bushing Dies. Gun will be primarily used for elk hunting out west.
I followed Berger's starting point of 70.5 grains of H1000, and shot .015, .020, and .030 off the lands.
See the first imagine below - the .030 off the lands shot the best (by far). (Image without a circle)
So, 70.5gr is pretty light for H1000 in a .300 WM, and decided to bump the powder charge up to 74gr (imagine with the red circle). This caused the groups to open up. This had zero pressure signs.
Question is, from here, do I bump up to say 75 gr and keep going until I see pressure - then tweak the seating depth again? Was hoping that the powder increase would not open the groups that much. I am new to this precision reloading.
Like this the 41.5 grains and 41.0 grains are really close together. So load up 5 rounds of each. See which one groups the tightest. After that then start messing with the seating depth. Hope this helps.
You should load 30 thou jump and shoot a ladder from 74 to 76 grs at .2 increments look for a speed node, a flat spot, a spot where the speed stays the same. And look for pressure. A good node is were the fps ES is less then 20 fps across .4 grs/ 2 shots or more. Load the middle of that node/powder charge. And then test your jump again at 5 thou increments and since 30 thou jump was best before go up and down from there, 20, 25 30, 35, 40. When you shoot these you should see a pattern to follow to the best load. See ocw and Satterlee load development videos.Hi All,
So I have a Bergara Premier Highlander in .300 Win Mag that I am working on some hand loads for. I am using Berger 215's, H1000, Norma Brass, CCI 250's, and Redding Type-S Bushing Dies. Gun will be primarily used for elk hunting out west.
I followed Berger's starting point of 70.5 grains of H1000, and shot .015, .020, and .030 off the lands.
See the first imagine below - the .030 off the lands shot the best (by far). (Image without a circle)
So, 70.5gr is pretty light for H1000 in a .300 WM, and decided to bump the powder charge up to 74gr (imagine with the red circle). This caused the groups to open up. This had zero pressure signs.
Question is, from here, do I bump up to say 75 gr and keep going until I see pressure - then tweak the seating depth again? Was hoping that the powder increase would not open the groups that much. I am new to this precision reloading.
You did good on the seating test on low low powder. Now you need a chronograph. The best thing to do is load 1 bullet at say 72gr, then 1 at 72.2, 72.4 and so on. There will be a flat spot where your fps is similar like 73.5 gr is 1650 fps, 73.7 is 1652 fps and 73.9 is 1657 fps. The area that you get a flat spot where the fps is really close together will be where you want to go back and fine tune with 4 or 5 shots to find the least amount of spread in fps.Hi All,
So I have a Bergara Premier Highlander in .300 Win Mag that I am working on some hand loads for. I am using Berger 215's, H1000, Norma Brass, CCI 250's, and Redding Type-S Bushing Dies. Gun will be primarily used for elk hunting out west.
I followed Berger's starting point of 70.5 grains of H1000, and shot .015, .020, and .030 off the lands.
See the first imagine below - the .030 off the lands shot the best (by far). (Image without a circle)
So, 70.5gr is pretty light for H1000 in a .300 WM, and decided to bump the powder charge up to 74gr (imagine with the red circle). This caused the groups to open up. This had zero pressure signs.
Question is, from here, do I bump up to say 75 gr and keep going until I see pressure - then tweak the seating depth again? Was hoping that the powder increase would not open the groups that much. I am new to this precision reloading.
Seating depth does affect chamber pressures, but to an extent there is an inverse correlation between internal case volume and pressure, with velocity as a constant - meaning as case volume increases and velocity stays the same, pressure decreases.If changing the powder charge weight, changes the chamber pressure, how can changing the seating depth, not change chamber pressure? Isn't chamber pressure and velocity directly correlated?
Well... there's a lot of info and great tips. If I may help? I'll keep it as simple as possible. You can start at 70.5 and load one bullet .3 grains hotter each time until you see pressure (ie: 76 or more) Be careful!!! Use your corny! This OCW test will show you a node where the MV will flatten out over 3 or so shots. No target needed. Yes I said no target required. Just the chronograph. Choose the middle load of the three and then do seating depth testing starting at max mag length or .005 off of jam. Load 3 shots per string same depth then .003 deeper for the next string and so on.The node will show itself here. You are looking for the groups to tighten then open watching yet again the ES& SD's of each string. Target required here in conjunction with the crony. You are tuning for barrel harmonics now. When the best 2-3 groups are found across approximately .006 of jump, use the longest seating depth that is visible minus .001. This allows you to stay in the node as your throat erodes. Good luck!Hi All,
So I have a Bergara Premier Highlander in .300 Win Mag that I am working on some hand loads for. I am using Berger 215's, H1000, Norma Brass, CCI 250's, and Redding Type-S Bushing Dies. Gun will be primarily used for elk hunting out west.
I followed Berger's starting point of 70.5 grains of H1000, and shot .015, .020, and .030 off the lands.
See the first imagine below - the .030 off the lands shot the best (by far). (Image without a circle)
So, 70.5gr is pretty light for H1000 in a .300 WM, and decided to bump the powder charge up to 74gr (imagine with the red circle). This caused the groups to open up. This had zero pressure signs.
Question is, from here, do I bump up to say 75 gr and keep going until I see pressure - then tweak the seating depth again? Was hoping that the powder increase would not open the groups that much. I am new to this precision reloading.