Q&A: 300 WM with 210 gr VLD Hunting Project

[Mc Fraser]

Finally got all my equipment together and finish the CBTO sweet spot test.
I measured CBTO with 3 different techniques, first with the Hornady gauge average 2.7505" then with a rod to the tip of the bullet and did some math to come to CBTO or 2.7650" and the last one was with the sharpie method and got 2.7555".
I went with 74gr of H 1000 in 0.020 increments @ 100 yds start from SAAMI setting depth up to 2.7450" CBTO. I forgot to take a picture of #II so I used my bench notes. #V is 2.7450" CBTO and #I is SAAMI seating depth.
What is your first impression?
My questions are:
- should I even bother with a ladder test?
- should I use another powder?

TIA.

 

[ShtrRdy]

It would have been nice if you shot a group with the cartridges of the same length. That way you could see if a particular length causes a better group.
You could measure the "X" and "Y" coordinates for each shot and plot them by grouping them with the same lengths.

 

[Mc Fraser]

I don't know why and how to do that, but each picture represents 6 shots of the same length. Because of the statistical nature and after calling on Berger, I thought 3 is not enough, 6 is overkill hahaha. But yeah each picture represents an individual target with cartridges of the same length. 1 square represents 1 MOA @ 100yds.

 

[ShtrRdy]

Oh, okay. Maybe we need a legend to define what a,b,c,d,e,f and I,II,III,IV,V are?

 

[Mc Fraser]

Good point. Sorry about that.
I though V represents each set of 6 cartridges with the same length.
a to e represents each shot in chronological order for each set.
I = 1 in Roman numbers
II = 2 etc

I - 2.6650in CBTO, also this is 3.3400in cartridge length
II - 2.6830in CBTO
III - 2.7030in CBTO
IV - 2.7250in CBTO
V - 2.7450in CBTO
CBTO- cartridge base to ogive length.
Does it make sense now?

 

[Mc Fraser]

I - vertical 1.5 MOA, Hz 1.2 MOA (I didn't count "a" because it was the cold bore shot)
II - hard to say but I believe vertical is 2.75 MOA, Hz 1.5 MOA
III - vertical 2 MOA, Hz 1 MOA
IV - vertical 1.25 MOA, Hz 1.5 MOA
V - vertical 2 MOA, Hz 1 MOA

This is all new to me, I'll through a stab in the dark and pick IV? What do I do now?
I should mention that the rifle wasn't zero and I was aiming at the big diamond center.

 

[Greyfox]

Given your seating depth results I would take I(.015"OL), starting with your 74gr load an run 3 shots each in .5gr increments. Watch for pressure signs as you get in the 75-76gr range. Your test groups could be indicating your current test charge is well out of the node. I'd chronograph these charges, and let the barrel cool a few minutes between groups. If your groups do not respond to this charge weight test, I would then consider a powder change assuming something else isn't going on with your rifle, rest, etc.

 

[Mc Fraser]

Given your seating depth results I would take I(.015"OL), starting with your 74gr load an run 3 shots each in .5gr increments. Watch for pressure signs as you get in the 75-76gr range. Your test groups could be indicating your current test charge is well out of the node. I'd chronograph these charges, and let the barrel cool a few minutes between groups. If your groups do not respond to this charge weight test, I would then consider a powder change assuming something else isn't going on with your rifle, rest, etc.

Thanks. As I said this is new to me, what was your train of thoughts that lead to I?
In my inexperience I would have pick IV due to low vertical.
I think I will try both
Should I even bother 0.020, 0.030, etc?

 

[Remmy700]

I did same test as u few months ago except running 208 eldm in my 300. There is always a node in the 75 area and usually around the 77 area as well but in most of my rifles my ceiling was around that 77 realm also so I always stay in the lower node. I am going back out this weekend to do 215 bergers and see how they do.

 

[Greyfox]

Thanks. As I said this is new to me, what was your train of thoughts that lead to I?
In my inexperience I would have pick IV due to low vertical.
I think I will try both
Should I even bother 0.020, 0.030, etc?

My impression of your groups is that they are all tending to fall into similar sized groups, none of which stand out as particularly tight. You could certainly start with IV, but my idea would be to start closest to the lands which generally tends to produce the best results for VLD's , while offering higher powder capacity/lower pressure. The goal at this point is to see if any of the powder charge levels influences group size. If one does, I'd confirm it, then take a look at fine tuning seating depth.

 

[Mc Fraser]

I went with #4 for now and played with distance to lance at 100 yds. Each square on the target is 1in in size.
1 = 2.7150in or 0.040 in off the lands
2 = 2.7200in or 0.035 in off the lands
3 = 2.7250in or 0.030 in off the lands
4 = 2.7300in or 0.025 in off the lands
5 = 2.7350in or 0.020 in off the lands
AV = average MV measured with Labradar

What do you think about these new groups? on #1 please ignore the green part, 2 shots were placed by mistake.
I guess the next step is to go at 500 yds and try playing with powder charge level?
My money is on #2 & 4 because of low vertical, if I ignore the wild one on each group, but I'm guessing at this point.
Should I move closer to the lands? I'm already at 20 thou, next step will be jamming into the lands?

A few things that stand out, I used 74gr H1000, my barrel is 28/29 in, I noticed slight signs of pressure on the primers. It seems weird because most of the articles I read they say 75-77 is ok. Even weird is that I was playing with some 200gr Sierra SBT I had to lay around with IMR 7828 and at 1.5 gr below max load from Sierra book, I noticed the same pressure signs, at 1gr below max load the primer had serious signs of pressure. The bullet is seated at 3.34in as per Sierra reloading book.
I don't really care that the book was off but I'm thinking that something like this odd will reveal something odd and/or rare about my rifle? Anything that you could think off?

 

[Remmy700]

What primers u running brother

 

[Mc Fraser]

Federal 215M Gold Premium ones

 

[Remmy700]

So we have talked about this before and I know there are several people that do seating depth first but just by velocity numbers I tend to not do that. I always pick like .015 off lands and I do charges first. And look for groups a little and really focus on my SDs. Once I get something that is grouping well with super low SD numbers in the velocity ball park I am looking for then I press on with tinkering with seating depth. From what I have noticed seating depth changes don't mess that much with SD numbers unless A. U are getting compressed or B. U are jamming. That huge area in between numbers don't seem to flex that much. Your charge seems really low for seeing pressure signs that early that is a very mild load. Your powder choice for sure is on point H1000 is for sure one of the gold standard powders in the win. Let me measure a few of my loads and see where are sitting as compared to me and 215 and 208 loads. Maybe your rifle is just short throated, something is def off right now. Not saying u are wrong or anyone else is but to me why try a seating depth test with a load that has ES of 50 I mean u may see a little opening and closing of groups I guess but to me u will see way more when u have a powder charge already that is producing low single digit SDs. Just my way is all.