Is this correct

[Smkngstv]

I have a colt copper 2012 308,getting ready for ladder test using 3 different powders

Varget-starting at 41 gr up in.5 gr increments to 44

Vihtavuori n150-starting at 41gr up in .5 gr increments to 45 gr

Cfe 223-starting at 46.5 up in .5 gr increments to 49 gr

Bulletts-Berger 168 grain bt target

Lapua brass

These are what I have for supplies ,I used a hornady oal gauge and get 2.950 tight to lands I want the rounds to fit in mag so would like to start with coal of 2.850 but all the books say to use 2.810. Will 2.850 be a good place to start.i have always followed the specs given in loading books so I am looking for some help or suggestions.thank you in advance

 

[Bob 964]

In a ladder test, I suggest you you fire a string of 20 or more shots at a target 300 yards or more away. Beginning with your starting powder charge weight and proceeding upward, each successive shot should have an incremental powder charge weight of 0.3 grains. I think the 0.5 grain increment you suggest is too great for the .308. The charge weight of your starting load should be the maximum charge weight for that cartridge with that bullet, minus a decrement that is 20 times the 0.3 grain increment, or 6.0 grains.

I looked in the Hodgdon and Vihta reloading catalogs (I have more confidence in max loads recommended by the powder manufacturer than the bullet manufacturer) and found the following max load weights for the 168: Varget - 46.0; CFE 223 - 49.0; and N150 - 44.5. So... I would start the Varget at 40.0; the CFE 223 at 43.0; and the N150 at 38.5 and go up in 0.3 grain increments.

I do all of my OCW and ladder testing with the bullet seated at the depth at which the ogive touches the lands. This ensures that the bullet is essentially "zero balanced", and is neither jammed nor jumped. Once I find the optimal powder charge weight, then I experiment with the seating depth.

This is what works for me. Whatever you decide, be careful to look for pressure signs as you do your testing.

 

[Smkngstv]

In a ladder test, I suggest you you fire a string of 20 or more shots at a target 300 yards or more away. Beginning with your starting powder charge weight and proceeding upward, each successive shot should have an incremental powder charge weight of 0.3 grains. I think the 0.5 grain increment you suggest is too great for the .308. The charge weight of your starting load should be the maximum charge weight for that cartridge with that bullet, minus a decrement that is 20 times the 0.3 grain increment, or 6.0 grains.

I looked in the Hodgdon and Vihta reloading catalogs (I have more confidence in max loads recommended by the powder manufacturer than the bullet manufacturer) and found the following max load weights for the 168: Varget - 46.0; CFE 223 - 49.0; and N150 - 44.5. So... I would start the Varget at 40.0; the CFE 223 at 43.0; and the N150 at 38.5 and go up in 0.3 grain increments.

I do all of my OCW and ladder testing with the bullet seated at the depth at which the ogive touches the lands. This ensures that the bullet is essentially "zero balanced", and is neither jammed nor jumped. Once I find the optimal powder charge weight, then I experiment with the seating depth.

This is what works for me. Whatever you decide, be careful to look for pressure signs as you do your testing.

Thank you sir I will make some adjustment on the powder weight,and will do more research on the olive touching the lands,I think that this measurement will be to big for my mag

 

[Smkngstv]

So it seems to me that I use the coal to fit in mag period,I do not want to single feed.so I should only use 2.810 as my coal and play with different powders and weights to find my best group correct

 

[Bob 964]

As a point of clarification, I shoot a bolt gun so I don't worry about magazine length. MtnCreek's concern about loading a cartridge that won't feed through your magazine is a legitimate one.

 

[Smkngstv]

IMHO, if I wanted to bullet to touch the lands, I would reduce neck tension to 0.001 to 0.002 and let the bullet complete it's seating (a few tho) on closing the bolt. That would give you consistent bullet to rifling. I don't load Bergers, but I have read where they suggest loading to lands for some of their bullets. If this is going to be a bench-rest or similar, loading one at a time may be worth it to you.

For my taste in 'chooting', I would see what bullet length functions 100% in my tightest mag and go with that for initial workup, depending on where that put my bullet in relation to rifling. With a Horn A-Max and SMK, somewhere between 0.015 to 0.030 jump is where I'll end up, assuming length fits the mag.

Good luck and that sounds like a cool rifle. I had never heard of it until today.

Here is a picture of the rifle it has a night force scope 3.5 x15x50

 

[P7id10t]

Here is a picture of the rifle it has a night force scope 3.5 x15x50

Nice.
I suggest you load to magazine length. I regularly load SMKs for my AR to 2.816, which just fits into the magazine.
Single shot loading an AR sucks donkey schlong.