So since I've only bought and loaded Sierra's ammunition so far for my M1A, I decided to buy the manual. I have not been able to find it and last weekend Bass Pro had it for 45$ so I picked it up.

I have been told they had a equations of bullet flight section dealing with the math behind bullet flight (a section I was looking forward too as I've been told about it), but more interesting and kind of annoying is the loads in the books I got at home.

168gr Ammunition ... 308 Win .... Varget .... 2.800 OAL
Richard Lee .. 46gr ... 2731 fps ... Non-Compressed
Hodgdon ...... 46gr ... 2731 fps ... Compressed ... Win Case & Fed Primer
Sierra ..........43.5gr ... 2700 fps ... Non-Compressed ... Fed Primer & Case

Soooooo which Max load should I be following?

My rifle doesn't seem to mind the 43grs I loaded. But I am wondering about this.

Dimitri

Are you loading the max load first?? Dimitri come now, you know better. right?

I hope so. At any rate, the place on the planet the folks work up their loads makes a difference, case volume per manufacture makes a difference,powder lots makes a difference. start at the minimum and work up ALWAYS. thats why we buy several manulas, because they are all gonna have a different result within a safe limit for the same components (sometimes). Thats why we start at the bottom and load UP from there.
I shoot NRA High Power, My Dad always used Winchester cases. He weighted them and measured internal volume with water and segregated them and used only the cases that were close to the same or THE SAME. I use Federal Match brass, Federal does all the work for you.

I'm no where near max per the 2 sources at 43gr. It is 7% under max or so. But Sierra claims I am right next to max loadings.

Dimitri

Watch your cases. They will tell you when your to hot. I alway use 41.5grains of IMR4064 in Federal match or WW cases under a 168gr Sierra Match King.
Also as you are aware Im sure the M1A is powder sensitive, so beware. IMR 4064 seems to be the perfect powder for the M1A and the M1G. IMHO.

FWIW, this is my 2 cents as a wildcat user...

All maximum data published are RECOMMENDED figure.
They are written as high as the writer (or their lawyer) dare or feel reckless enough to.

YOU on the other hand, have to observe and load accordingly.
It is a function of your observative-ness (is there such a word?) and experience that counts when you are rolling your own.

Regardless of what a data book said, your rifle may just happened to have a tad of tightness (or looseness)in its barrel,
and there goes the THEORETICAL pressure figures.
Or any other small variations such as batches of gun powder or primer, weight of projectile,
the coefficient of friction or hardness of the jacket material etc.
can vary the pressure within the chamber greatly, and in some cases, cause catastrophic failure!!

YOU are NOT supposed to FOLLOW the max, you are supposed to use them as a guideline.

IF AND ONLY IF, as you creep to a (any) max figure, your cartridge brass and primer does not show any sign of over pressure,
you may increase (a little) the load and push the envelope, and go to a next max figure and so on.

Added to that, if you are loading to MAX or NEAR max figures,
you will need to start from beginning again whenever you are using new batches of powder, primers, cases, projectiles or new gun.
The little variation may just be enough to cause the gun to fail, and you are placing your limbs and head nearby when it does..

You are an engineer Mr. D. so approach the challenge in engineering way, divide and conquer..
After all guns are a logically predictable mechanical device, unlike the individuals who use them..

Dimitri wrote:

Hodgdon ...... 46gr ... 2731 fps ... Compressed ... Win Case & Fed Primer Sierra ..........43.5gr ... 2700 fps ... Non-Compressed ... Fed Primer & Case

I used Federal and Remington cases for my .308. I rely mostly on Hodgdon data when I reload. I found that I could not even load the max charge for Varget in Federal cases even when compressed. I could get more powder (1 to 1.5 grains more) in a Remington case. In my .270, the Winchester cases hold more than the Remington. I expect that would carry over for .308 cases. With less volume in a Federal case, I would expect pressures to be higher and it looks like the data you collected confirms that.

+1 on the gelan post !!!

Remember this !!! You've answered your own question........ You knew it all along.......must of forgot with all that new knowledge your obtaining lately !!!

So if Manufacturer "A" uses Winchester Brass they can put in more powder then Manufacturer "B" can that uses Remington Brass. Therefore what is "safe" in Manufacturer "A" opinion maynot completly apply according to Manufacturer "B".

Every Varget load online seems to be 43gr +, no matter what the case. Most loads hovering 44-44gr which seem to produce the best accuracy with the 168gr SMK.

Overall from when I was data mining for what to use, many seemed to load compressed loads which are safe per Hodgdon, varying load weights but still compressed loads.

2 reloading manuals list 46gr, one from the powder manufacturer, and one not. Sierra lists otherwise, my loads are well enough below max per the powder manufacturer. Its not like I started by loading compressed charges from the start.

Dimitri

'Mitri....I must, by the Rules of Commonsense, agree with everyone else mate.

However, I think that the Sierra figures are either a misprint (they appear to be for a faster powder and are identical to the next fastest ADI powder) or they are, as Gelan points out, covering their butts against litigation.

The manufacturer of Varget, or as we know it out here AR2208 list the following data:

Thales (ADI)

.........................................................................................Starting Loads.....................................Maximum Loads

Bullet Wt (grains).........Powder Type.................Powder Wt (Gr)....Velocity (fps).................Powder Wt (Gr)...................Velocity (fps)

168gr.............................AR2208 ((Varget))..........42.0gr.................2520 fps........................46.0gr C (Compressed)........2730 fps

As the others all stress mate, and yeah I know, I'm preaching to the converted, start low and work up watching for pressure signs.

Cheers, Vince

Good to know Vince.

Dimitri

Did Sierra list what they used for a test rifle? As a general rule "universal receivers" tend to produce higher velocities with less powder. Otherwise....well everyone else has already said it! Just be safe.

I just bought the same manual and many loads were worked up using savage rifles with 26 in. barrels, including 308 win.

I've never been disappointed in the accuracy of the loads Sierra publishes for their Bullets alot of other manuals won't even tell you which one worked the best under their circumstances. Their match load for Rl 15 in the 5th edition is still the one I use. It also uses a Savage rifle. Which edition was on sale?

5th Edition was the one I picked up.

Dimitri

I need to update.............Mines the 3rd edition !!!