Working up a new load.

[SuperiorRifles]

I'm curious to see how other people work up a new load. I have my very basic way that works pretty good for my long range hunting loads. But thought it would be great info to see how other people go about working up a new load.

1)How do you go about finding the exact powder charge? (Finding the "node" or max safe pressure)
2)How do you find the optimal seating depth?
3)How do you know you have the most accurate load for a particular long range rifle?

In another post, I was asking about shooting 168 VLD's out of an 8 twist barrel, then I did some testing at 700 yards. The accuracy was less than desirable. I'm about to try and work up a load and see how good I can make the 168's work. (this is more of a backup load for when the 180 VLD's are not available) Just trying to look outside of my very small box. Thanks, Ryan

Ryan

 

[Hoier]

I start by shooting a ladder in small increments starting low and going fairly high cause I also wanna find my guns max. Then the shots that land together vertically I pick a powder charge in the middle of those that land together. Then I tinker with seating depth in .003 increments and shoot 5 shot groups at 300 and pick the one with the lowest vertical.

Edit to add: if my range had farther then 300, I would shoot farther.

 

[BoydAllen]

I do it in similar fashion, loading at the range.

 

[jsthntn247]

Boyd would you mind posting a pic of your range loading setup?

 

[BoydAllen]

It is put away right now and I think that I will leave it that way for few days. I generally only unpack and set up at the range, and it is 107 today so it may be a few before I get to the range. Really, the only provision that needs special attention is if you are going to weigh powder. For those few occasions that I do that, I have a glass front scale wind box that I use. I have put it up in posts before so you might do some looking around. If you can't find it, PM me with your email address and I will send you a picture. Other than that, and figuring how to clamp your press and powder measure to a table, that is pretty much it, except for having a way to transport things that is convenient and keeps things from banging together and being damaged.

 

[Nomad47]

Boyd, just curious, where is it 107 degrees?

 

[BoydAllen]

It made it to 108 today in Fresno, CA, and then we got a light sprinkle and a little thunder.

 

[Nomad47]

I've been thru Fresno numerous times. Covered flooding there once for ABC News. And maybe a mass murder? My memory is a little foggy on that one.

 

[SuperiorRifles]

So, lets take it a step back before the powder charge. Case prep. What's your process for case prep for a very accurate long range hunting round. Do you prep like you would for a competition even for your long range hunting rig? My case prep has been full length re-size with a removable neck bushing that would produce a .003" neck tension. I would then trim cases to insure same length. Chamfer case mouth inside and out. Load and shoot. The neck clearance in my chamber is .003" for my unturned brass. Would it be beneficial to turn the necks to get a more concentric neck if you gain .001" or so of neck to chamber clearance?

Ryan

 

[BoydAllen]

What brand of brass?

 

[SuperiorRifles]

What brand of brass?

Hornady 7mm LRM

 

[BoydAllen]

How is the neck thickness runout?

 

[BoydAllen]

I was not familiar with the cartridge so I did a little research. It looks like a good long range choice, that is somewhere between a 7mmWSM and a 7mm Mag. Let's see if this link works so that others who may not be familiar can learn about this new cartridge.
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&ved=0CEMQFjAC&url=http%3A%2F%2Fsite-media.net%2Fgunwerks%2F7LRMarticle%281%29.pdf&ei=fbYTUpLCK9HCyAGB4oDQAQ&usg=AFQjCNEEyBVtwvlv79d0xGKxxUGEiicUWw&sig2=JJRoMIcvw71Fn22jzBbmiQ&bvm=bv.50952593,d.aWc

Yep, it worked. Interesting read

 

[SuperiorRifles]

I was not familiar with the cartridge so I did a little research. It looks like a good long range choice, that is somewhere between a 7mmWSM and a 7mm Mag. Let's see if this link works so that others who may not be familiar can learn about this new cartridge.
http://www.google.com/url?sa=t&rct=j&q=&esrc=s&source=web&cd=3&ved=0CEMQFjAC&url=http%3A%2F%2Fsite-media.net%2Fgunwerks%2F7LRMarticle%281%29.pdf&ei=fbYTUpLCK9HCyAGB4oDQAQ&usg=AFQjCNEEyBVtwvlv79d0xGKxxUGEiicUWw&sig2=JJRoMIcvw71Fn22jzBbmiQ&bvm=bv.50952593,d.aWc

Yep, it worked. Interesting read

I haven't checked the run-out yet. I'll check it tonight.

It's basically a 375 Ruger necked down to 7mm. I really like it, as it has a lot to offer the long range hunter. You can buy brass and dies from Gunwerks.

 

[SuperiorRifles]

How is the neck thickness runout?

It measures .0015" runout on the case neck.

 

[BoydAllen]

If I were you, I would turn a small set of cases so that their necks were cleaned about 3/4 of the way around, and give them a try. This might also entail getting a bushing one size smaller. Unlike some, I don't mind combining a bushing FL die with an expander ball, and set them up so that the bushing sizes the neck so that the expander only opens the ID of the neck the barest amount so that it can hardly be felt as is passes back through the case neck. If I want more neck tension, I chuck the expander rod in a drill and polish its diameter down a little. I understand that John Whidden sells expander balls in different sizes.