Reloading Manual Differences

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911alertme

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First off I'm brand new to reloading. I picked up all the necessary equipment about 2 months ago but have been looking for powder ever since. I understand the shortage and the reasons for it all but damn is it frustrating for someone brand new to the hobby. After phoning all around the country for any suitable powder for the .308 I managed to secure some Varget (thanks Budget Shooter Supply:)).

I have read the ABC's of reloading as well as a few other reloading manuals. I feel I have a decent enough grasp on the subject but have a question. Since Varget is the only powder I have, it is what I have been looking at in the reloading manuals. I plan on shooting 150gr bullets. The following is data I have obtained from manuals for starting and max load for 150gr bullets:

Hornady 9th: 35.9-44.9
Lyman 48th: 42.5-47
Nosler's Website: 42.5-46.5
Lee 2nd: 44-47
Hodgdon's website is currently down so I don't have this data.

Hornady recommends a max load that is getting close to starting loads from the other sources. Why is this and what do you do when there are discrepencies like this? Also, if anybody has anything else from other sources I would be interested.

Thanks,
Spencer
 
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Since there are many variations in chamber and bore dimensions, among the various rifles, and there will always be lot to lot differences in components, there will always be differences from manual to manual.
 
You kind of just have to use your better judgment and remember you're better off starting a little light than a little hot.

That being said and given the numbers you provided, I would start at 41gr and work up, but that's just my .02 cents.
 
Hornady 9th: 35.9-44.9
Lyman 48th: 42.5-47
Nosler's Website: 42.5-46.5
Hodgdon's website is currently down so I don't have this data.
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Nosler 6 Manual shows 44.5 to 48.5

These reloading guides are just that, a Guide and not a Bible. Some companies will be more conservative than others based on liability. It seems in the last 25 years that the guides are much more conservative than they were back 25 years ago. Look at several manuals, what they are using for primers and cases, what kind of crimp and then start low and work your way up in your gun with your chosen components.

Given this data, I would start at 42.0 and then work up to where I would like to be.....safely :)
 
Yukon1911 said:
Look at several manuals, what they are using for primers and cases, what kind of crimp and then start low and work your way up in your gun with your chosen components.
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The components, other than powder, do make a difference:
- certain cases can take more pressure, or less pressure, and their loads reflect this
- certain primers ignite certain powders differently
- certain crimping changes the pressure of powders, so it depends on crimp (if any) for that manual
- and most importantly, the design and engineering on a bullet makes a difference: bullet plating, jacketing and such change pressures and what pressures they can handle

It is a science of its own, so keep learning and start at the low end of the books!
 
I would start at 43.5 and work up until I see pressure signs. Then go home and review data. I would bet your best results will be in near max loads in the 46-48 grain. But work up to it like always. I loaded 165's for my buddies remington and 44.5 was the best. That is over max in some books and under in others.
 
The Lyman manual data is from a universal receiver and a test barrel, the test barrel will have a minimum size chamber and bore dimensions. This test barrel will give the highest pressure readings due to the smaller chamber and bore. The test barrel will be equipped with a pressure transducer and will give direct pressure readings.

The other manuals will list a specific firearm used, the firearm will be equipped with a strain gauge which is glued to the barrel and then fired with a test cartridge of a known chamber pressure. This will calibrate the pressure readings and all test data will be from this zero reference point.

A universal receiver, test barrel, and transducer will give the most accurate data based on minimum chamber and bore dimensions, meaning the highest possible pressure readings. The readings from specific firearms will be pressure "estimates" based on strain gauge calibration, strictly based on the firearm used. When the data is compared between manuals with specific firearms you will see the widest variations in chamber pressure and loading data.

The pressure data will vary on bullet design, case capacity of the cartridge case used and the lot number of the powder, actual bore dimensions and the surface of the bore.

Therefore data from a universal receiver and test barrel are the "MOST" accurate, and when a specific firearm is used the data is a "ball park" average.

Average and start low and work up, your first loads will have the primer protruding from the rear of the case. As the load and pressure increases you will reach a point where the primer is even with the base of the cartridge cases. At this point the pressure is great enough to cause the brass to stretch and meet the bolt face and seat the primer flush. From this point forward you will need to watch your primers for flattening and excess pressure signs.

Watch the animated image below and the primer movement and the case stretching to meet the bolt face.

HeadClearance_zps03634b1b.gif


Once the primers are flush with the base of the case start paying attention to pressure signs, the primers and cartridge case will tell you when your are approaching maximum pressure. The manual maximum load may be less or more in your firearm and they are only guesstimates for "YOUR" firearm.

Below is Quickload data estimate chart, using the same data from the Lyman 49th edition, .308 Winchester, 150 grain Hornady bullet using the max load of 47 grains of Varget. Maximum rated pressure for the .308 Winchester is 60,191 psi.

Lyman manual, 47 grains of Varget, 2891 fps, 58,000 psi
Quickload data, 47 grains of Varget, 2872 fps, 57,599 psi
The Lyman data is a actual tranducer pressure reading, the Quickload data is a software generated "guesstimate" and very close to Lyman test data. Shoot the same load in your rifle and it could be lower or higher than what I have listed here because each firearm is different along with the components used.

308-150_zps3bd6d527.jpg
 
Huge variation in barrels. We used to use tight barrels to shoot military ball ammo. .3065" was common. Remington rifle have very deep throats and take larger powder charges.

Satrt low and see if you can work up. I have seen a Start load blow a primer badly.

With a new rifle I load 5 shots each in 0.5 gr increments to see what works. I am prepared to bring some it home and pull the bullets.
 
911alertme said:
First off I'm brand new to reloading. I picked up all the necessary equipment about 2 months ago but have been looking for powder ever since. I understand the shortage and the reasons for it all but damn is it frustrating for someone brand new to the hobby. After phoning all around the country for any suitable powder for the .308 I managed to secure some Varget (thanks Budget Shooter Supply:)).

I have read the ABC's of reloading as well as a few other reloading manuals. I feel I have a decent enough grasp on the subject but have a question. Since Varget is the only powder I have, it is what I have been looking at in the reloading manuals. I plan on shooting 150gr bullets. The following is data I have obtained from manuals for starting and max load for 150gr bullets:

Hornady 9th: 35.9-44.9
Lyman 48th: 42.5-47
Nosler's Website: 42.5-46.5
Lee 2nd: 44-47
Hodgdon's website is currently down so I don't have this data.

Hornady recommends a max load that is getting close to starting loads from the other sources. Why is this and what do you do when there are discrepencies like this? Also, if anybody has anything else from other sources I would be interested.

Thanks,
Spencer
Click to expand...

Hodgdon recommends a max load of 47 grains with 150 gr bullets. I use a lot of varget with 168 gr bullets in 4 different rifles and usually end up at about 46 gr so I think the Hodgdon manual is correct. However, as always, work your way up to be sure. I would start at 43 gr.
 
Ganderite said:
Huge variation in barrels. We used to use tight barrels to shoot military ball ammo. .3065" was common. Remington rifle have very deep throats and take larger powder charges.

Satrt low and see if you can work up. I have seen a Start load blow a primer badly.

With a new rifle I load 5 shots each in 0.5 gr increments to see what works. I am prepared to bring some it home and pull the bullets.
Click to expand...

Sometimes I take some sized and primed cases to the range along with a Lee loader and scale and work my way up one at a time. That way I don't have to pull any apart or waste any time.
 
aspenkarius said:
unless i missed something wouldent the best rout be to go with the data published by who ever makes the bullet? speer/hornady/sierra etc?
Click to expand...

I agree with aspenkarius.I am by no means a extensive experienced hand loader,but a recent experience has convinced me to go with the bullet manufactures recommendations.For example, bullets of the same weight from different manufacturers can have significant differences in the bearing surface and give various pressures with the same amount of powder.
 
Dunk said:
I agree with aspenkarius.I am by no means a extensive experienced hand loader,but a recent experience has convinced me to go with the bullet manufactures recommendations.For example, bullets of the same weight from different manufacturers can have significant differences in the bearing surface and give various pressures with the same amount of powder.
Click to expand...

x3, depending on the brand of bullet you are using, I would use that brand of manual for the data. Unless you are using something more generic like winchester PP, remington core lokt etc.
 
"...Reloading Manual Differences..." Manuals reflect the data obtained under the conditions and with the equipment used on the day of the tests.
 
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