.308 / 7.62x51

**Disclaimer: This is not reloading advice or instruction(s). This is what I have done to achieve a particular set of results. This website urges readers to NEVER take a loading recipe from the internet. Check the manufacturer of the projectile and the powder before reloading. Typos can maim and kill.***

Point of this story:

Consistency in what you can control will help you find the right load for your rifle for your application. Consistent brass, consistent power charge, consistent bullet weights, consistent shoulder height, and consistent seating depth. This data is for .308, light bullet of 150 grains. There is no attempt to push the envelope to gain velocity for the sake of velocity. These are not 'Bubba's pissin' hawt loads.' 

Nice Things

The reason we can't have nice things is because we failed to concentrate. Yep. Completely shanked one. 4 outta 5 dentists would agree that this is too wide a gap to have between front teeth. 

Target size in real life is 3 inches. If I am kind to myself, and exclude the stupid shanked one, then I get a .21" grouping. For me, that's gold. Platinum even. Below, I have listed the components and steps. Even better, using my chrono, I had a maximum difference in speed at muzzle of 2 feet per second. Yes, 2 fps. A standard deviation of 1. My best ever. 

This was part of a ladder load. All loaded to the same amount of powder. All had same -0.002 shoulder bump lower than SAAMI spec. Distance = 100 yards.

Always check your brass after firing each round for primer flattening, signs of pressure, brass damage. I do after each shot so that I don't shoot a 5 shot rung that is harming the brass or my rifle. 

How to choose the ladder load: 

Starting with varying grains method:

Some long range, world class shooters do same shoulder bump, same seating depth, and vary the .3 gr or .4 gr or some other range of grain charges until they find a grouping that looks good. Then they narrow the powder charges again... Just like most reloading manuals do. Here's from my Hornady manual, 10th edition, p472. 

Notice that Varget has a 0.3 gr increment. RL-15 has a 0.8gr increment. These are not interchangeable. The one load data for one powder is not a guide for a different powder. 

One way to do a ladder load ¹. For our example, let's pretend that my rifle on the day I shot my ladder recipes had these environmental variables:

1. Wind speed and direction v, 2. Barometric pressure w,  3. Temperature x, humidity y, 4.Elevation z

The best groups using RL-15 at ladder rung 45.4 and rung 47.2. Actually I used Varget. But this is a pretend example. 45.4 to 47.2 is 1.8 grains. So, next time out, I would have rounds at half that ladder distance. 46.2, 47.0 ***If I have time and want to spend the components, I might do 0.4 increments. So, 45.9, 46.3, 46.7, 47.1 *** If I find my best groups at 46.3 and 46.7, I would then do another load test at 46.4, 46.5, and 46.7. Hopefully, my groups are tighter and tighter. And finally I discover that 46.5 is the best for my rifle, this bullet, this powder, this primer, this brass, at my particular environmental conditions. 

Now I need to test seating depth - aka how far down do I seat the bullet in the case neck. I measure at the base to ogive not base to tip. I create the next ladder rung based on seating depth not powder charge. They all have the same powder charge of 46.5 RL-15. So if bullets 1 through 5 are seated at original seating depth, bullets 6-10 are 0.001" deeper, 11-5 are 0.002" deeper, bullets 11-5 are 0.003" deeper. 

I now test to see if the seating depth gives me better or worse groups. I also will use a chronograph. If the muzzle velocity remains tight (little variation), then I am at least consistent. So, again, pretending, I discover that RL-15 at 46.5 grains, seated 0.001" deeper than book recommendation, provides me with 0.219" group at 100 yards. Well, then I have my load. Now I need to recreate these loads and test them as the weather changes. Some powders are temperature sensitive. Cold air is denser than hot air. A shot in the winter may be slower than one shot in hot weather. 

Starting with varying depths method:

Then Hornady manual says that for an SST 150gr bullet, I should have C.O.A.L. at 2.735"

I will start with 47.2² grains RL-15 at 2.735" cartridge overall length and measure the ogive. That ogive measurement will be my "zero" starting point. Then I will create 5 more rounds with the ogive measuring 0.001" less than the first batch. Then do again at 0.002" deeper and 0.003" deeper. The results from my actually doing this with Varget are groups of 0.21", 0.27", and 0.3" as calculated by On Target Software. (Yes, paid for subscription). That is good enough for me. And it only required 15 rounds. 

Rifle:

Rifle: Savage 110 LRH, 1/10 Twist, 26" Barrel, Stock

Muzzle Break: Super Beast II

Bipod: Accu Tac SR-5 G2

Scope: Arken SH4-Gen2 6-24x50

Reloading Equipment:

Press: Redding T7

Turret: Creedmoor Sports Enhanced Press Head

Dies: Hornady Custom Full Size Resizing and Seating Die with Micrometer Seating Stem

Neck Bushing: .335

Crimping Die: Lee

Ogive & Shoulder Measuring Tools: Short Action Customs Shoulder and Ogive Modular Inserts

Calipers: some piece of crap from Amazon

Scale: some piece of crap from Amazon

Reloading Components:

Powder: Varget 44.90 gr (hand measured)

Bullet: Hornady 30302 SST 150gr

Base to Ogive: 2.039" 

Brass: Lapua .308 Large Rifle Primer 

Primer: Federal 210 LRP

Shoulder: -0.002" from SAAMI Spec

1 Ladder Loads and Statistics. If you spend any time on the reloading forums, you'll find at least 3 distinct type of people. People who are awesome and want to learn and share. People who only want to be negative or tell you that you are wrong. And people who make wildly stupid statements while criticizing but never offering anything themselves. Fortunately, the last kind of people are the least. Here's my favorite example. Erik Cortina and other precision, long range shooters often shoot 3 or 5 shot groups. I read a real, live post from some curmudgeon stating that "5 shot groups are statistically invalid. You need 15 or more. Anything less is just dumb luck and b.s." Well, let's assume curmudgeon is correct. Most of us can't afford in time or cost the amount of expenditure to do a 5 rung test with 15 rounds. That's 75 rounds per ladder test. If you want to, do it. I don't. That's more wear on my barrel than I want. That's 3/4 a box of primers. And for my .308, that's 46.5gr x 75 = 3487.5 grains of powder. Or 1/2 of a one pound container of powder. When I hit the lottery I still won't do it. For a different opinion, go here

2 Never start at maximum powder. Never. Reduce by a minimum of 10%. So 47.2 x .1 = 4.72gr less. 40.0 grains starting point.