308 load confusion - Please help!!

[ldlfh7]

Hello all -

I recently purchased some Sierra 125 gr spt pro hunter bullets I plan on making for yotes and maybe deer depending on how they do. While looking for a load I came across some inconsistent load data. I am loading with IMR-4895. Sierra 5th edition lists the min at 42.5 grains and max at 46.2 grains. After reading this I checked the Hogdon website for their data and it is quite different. They start out with a min at 48.0 grains and max at 51.8 grains. How is this so different? What should I do? My Lyman 49th edition suggests a min of 43 grains and max of 47 grains. Is the Hogdon website just plain wrong or what? Help, suggestions would ease my headache here. Thanks.

 

[nix4me]

Lee manual lists 48-51.8, both compressed

 

[steve4102]

Lee manual lists 48-51.8, both compressed

Lee data is borrowed from Hodgdon, stands to reason it's identical.

 

[ldlfh7]

So I guess my question is why is there variance?

 

[Haxby]

Agreed, there is a big difference between Hodgdon's 308/IMR4895 loads and what you find from some other sources. Don't know why. I thought about asking Hodgdon, but never did.
46 gr IMR4895 is not too hot in my 308 with a 150 gr bullet. Since I already know that, about that individual rifle, I'd probably start with at least 46gr with a 125.

 

[Rule3]

There is usually differences in test data.Different day, lot number, test barrel or gun, the phase of the moon whatever. Is it all the same exact bullet?

I have found Hodgdons data is usually the lower of them all. Not in this case They make the powder so their data is reliable. The manuals run many loads.

Without digging out my Lyman did they test the exact same bullet?

I usually take the average of the start loads and begin there as long as it is the exact same bullet.

 

[ldlfh7]

Lyman did test the exact same bullet. Only thing that worries me is the max listed by lyman and sierra are lower than the minimum charge for hogdon and Lee.

 

[Rule3]

As stated LEE data is complied from other sources, usually the powder maker. They never tested any of them.

Hodgdon made the powder I have confidence in their data. I would use the start load. But that's me. Look at it this way. If a compressed load is listed and you put in a non compressed load, than that you are good to go.

You also have to look at the different velocities. If you are not comfortable with the higher loads than use the lowest start load of all the sources. It's all good and will only change your FPS.

 

[Haxby]

If you're leery of the Hodgdon data, use the Sierra data. The lightest load I see listed is over 40 gr, and IMR 4895 works well with light loads. You have a pretty wide range of safe loads to choose from.

 

[ldlfh7]

Thanks for the replies. I am starting at 45 grains and going from there. With a difference of more than 4 grains I was worried but now I will work my way up looking for high pressure signs. I would really like to hit 3000 fps on this load for long range yote hunting.

 

[USSR]

I have found Hodgdons data is usually the lower of them all. Not in this case They make the powder so their data is reliable.

Hodgdon never made a powder in the entire life of the company. All their powders are made by others who stick the Hodgdon label on the cannister.

Don

 

[Rule3]

Well excussse me. Guess I should have said Markets the powder and has the test data for it.They have their name on it. Lots of it is made here at St Marks. Thanks for qlarifying that. I hope they tested it.

 

[cacoltguy]

In my reloading experience, data listed by the bullet manufacturers is usually very conservative compared to the data listed by the powder companies. (At least for the loads I shoot) The bullet companies are just protecting themselves from any liability issues. (Don't ask me why the powder companies aren't as concerned with this) Nearly all of my rifle loads are at or above max in the eyes of my Hornady manual, but perfectly safe according to the Hogdon data. I've almost never developed a load within the limits of the Hornady manual that would give me the long range performance I was looking for. The good groups of my load workups that fell below Hornady's recommended max charge were usually the low node of the spectrum. As always, work up your loads gradually and check for signs of over pressure, but don't freak out if your charge is at the high end or above max for the bullet companies reloading guide. The exception would be if you are shooting something like an M1A or Garand, in which case you need to be careful using any reloading guide that is based around data for bolt action rifles.

 

[243winxb]

So I guess my question is why is there variance?

At times, brass may be very different.