Discrepancy in load data

[Double_D]

I want to start using 168 gr. A-max in my .308 win for target shooting, but the the load data that I'm looking at is inconsistent. I don't know what I should use for starting load and what is the absolute max load.

Here is a table of the different load data.


My rifle is a Savage 10 FCP-K. Using 168 gr. SMK's, I started at 41.0 gr Varget and worked my way up to 46.0 gr in 0.5 gr increments without noticing any pressure signs. My best groups at 100 yards were with 44.5 gr Varget
.
Since it worked with 168 gr. SMK, can I start 168 gr. A-max at 41.0 gr?

Here are the components I want to use.
Bullets: 168 gr A-max
Powder: Varget
Primers: Winchester Large Rifle

[stilly]

There is really no CORRECT load, only RIGHT loads and WRONG loads. Wrong loads will injure you or your firearm.
Right loads will produce a safe shooting firearm.

That about sums up ALL reloading when it gets to the granular details.

Pick a load you want to try out, start low and work your way up once you notice signs of high pressure or degradation of accuracy then perhaps you should stop adding powder and settle back down to a lower charge. Then make a note of it and stick with it or try another. IT is pretty much that same method across the board. Different loads for different folks and guns...

[BigBronco]

You can drive yourself batty comparing too many sources for load data. The reason behind varying data is that these company's all do their own testing. Some test with test barrels and some with actual firearms. The manual should indicate what the cartridge was tested in. A bolt rifle will have different load specs that an M1A. Na M1A needs to be in a specific pressure range to operate properly.

If loading for a bolt rifle most of the data you find will be safe at the low end for a starting point, even the hottest of the low end. Watch for pressure signs as you work up your load. Load 4 or 5 of each charge weight as you work up and see how they perform at the range.

[Rbutler]

if im not mistaken the barnes and the amax are a longer bullet.

I know for a fact never use standard bullet data for barnes as they are copper and longer. Load data is based on bearing surface length NOT bullet weight.

start where you feel comfotable and work up.

[JMP]

Different guns, different bullets, different cases will have an impact. The nice thing about Varget in a .308 is that it's hard to overcharge it. Long barrel life and cheap brass--I say push it until the groups spread. 44s are about right for 168s. .308 needs all the velocity it can get..

But yeah, be safe..safety safety safety.

[pacrat]

There is ALWAYS discrepancies in published data. There is NO one size fits all BEST LOAD.

Rifles are like Wimmens, they're all fickle and have dietary prejudices.

I have dozens of load manuals from various publishers. None show the exact same loads.

Use them as guidelines. Always start low and work up slow. Your rifle will tell you what is best or Max. Just listen.

JM2c

[highpower790]

I use the same powder and starting at 41gr would be fine with the AMAX.

[stilly]

You can drive yourself batty comparing too many sources for load data. The reason behind varying data is that these company's all do their own testing. Some test with test barrels and some with actual firearms. The manual should indicate what the cartridge was tested in. A bolt rifle will have different load specs that an M1A. Na M1A needs to be in a specific pressure range to operate properly.

If loading for a bolt rifle most of the data you find will be safe at the low end for a starting point, even the hottest of the low end. Watch for pressure signs as you work up your load. Load 4 or 5 of each charge weight as you work up and see how they perform at the range.

****ing truth brah...

[Grunt81]

Keep in mind, some primers are hotter than others and shorter OALs can spike pressure as well. Load data should list those two variables as well as twist rate of the barrel used - faster twist rate can also increase pressure with a more abrupt engraving of the jacket rather than a slower one.

The only load data you have for the Amax is from Hornady - the guys who happen to actually make that bullet. I'd trust them. There is often a misconception online that manufacturers are conservative with their load data in order to avoid a lawsuit. I'd disagree with that statement. Take it as max charge for the listed OAL. Since an Amax is is really just meant for paper punching, no need to load it hotter than max and add unecesssary wear.

If I were you, I'd load five rounds each from 41.0 to 43.5 in 0.5 grain increments (as you did for the smk). That's 30 rounds. You probably already know the jump to the lands your rifle likes so I'd start there and see how the accuracy is. I'm sure you'll find a tight group somewhere in there. Plenty of people like the Amax and you did the right thing by getting the opinions of others.

Buenos Suerte.

[edwardm]

if im not mistaken the barnes and the amax are a longer bullet.

I know for a fact never use standard bullet data for barnes as they are copper and longer. Load data is based on bearing surface length NOT bullet weight.

start where you feel comfotable and work up.

Funny, because Barnes customer support told me *exactly* the opposite:
-----------
From Ryan Banks @ Barnes (9/24/14):

I have attached the load data that we have shot. The TSX and TTSX weight for weight use the same powder data. If there is a powder not included that you want to use you may use any other reliable data with an equal weight bullet.

Thanks
------------

I was looking at their load sheets, which don't list IMR-4350 for the 30-06, and inquired about using that powder. The above was Barnes' reply. Basically, grain for grain, use the same load data. Naturally I would start at the bottom and work up. The bands on the Barnes bullets act to reduce bore and chamber pressures, so it makes sense to me for Barnes to make that statement.

[J-cat]

DD:

What cases do you plan on using?

[Double_D]

DD:

What cases do you plan on using?

These. Once fired.

[Grunt81]

I've prepped some of those Federal cases but haven't loaded them yet.

Let me share with you what the consensus seems be on Federal .308 cases for reloading.

1) They are capable of good if not great accuracy with proper brass prep.
2) They are thinner, softer, and lighter than most other manufacturers.
3) The primer pockets are usually the first to go (enlarge too much) and the cases aren't suitable after that.

I'm not speaking from experience, just from the results of my .308 brass research. You'll find out for yourself.

Anyway, load with them with confidence and I'd have a back-up plan after 4 firings.

[AandO]

"If there is a powder not included that you want to use you may use any other reliable data with an equal weight bullet." Edwardm in post #10



This is the Proper answer.

My only inclusion would be "Bearing Surface" could also be a factor, rare but it should be looked at as well.

Absent Load Data for your Bullet, as long as you start at the low end you are good to go for equal weight Bullet Data.

[J-cat]

On point #2, FC cases are not thinner than most other manufacturer. That is not true.

FC 308 cases weigh from 174-180grs. They have slightly less capacity than Lapua but more than LC. They have the same capacity as WCC cases.

Your start charge of 41grs under a 168 is mild. Look at the following Sierra load data. They use the same components:

http://www.6mmbr.citymaker.com/f/sierra308Win.pdf