.308 charge data ?

[Rsadams]

Gona load some 150gr fmj for my .308 win for the first time useing IMR 4064. Looking in the hornady 9th edition it shows 38.4 start and 44.9 max. But the Speer manual #14 shows 43 start and 47c for max. That's a lot of diffence. Why is so one so much hotter than the other?

Iam just trying to find a mid power load to start with and that is very confusing. Just trying to check on the accuracy of an old Remington and got tired of buying factory ammo. Mid power in one book isn't even start in the other. Also if anyone would leave a nice shooting recipe for 150 gr fmj and IMR 4064 in .308 win. to compare? Its what powder I have right now.

 

[krumfola]

I just loaded some 308 with AA4064, 43.5gr is where I started. I'm using a 168gr BTHP.

Have you tried the 308 cartridge guide?

Here's the link:
http://www.accurateshooter.com/cartridge-guides/308win/

 

[Rsadams]

I just can't get over the spread in charge weights between the 2 books. I have been looking at some other data and most of it goes to 47 gr but that hornady book says 45 is max and the starting charges are way different.. The books can be so confusing..

I was going to start at 43 acording to the hornady data that would be about the middle of the road. Then I look in the Speer and it's barely a starting charge..

 

[Rsadams]

I just loaded some 308 with AA4064, 43.5gr is where I started. I'm using a 168gr BTHP.

Have you tried the 308 cartridge guide?

Here's the link:
http://www.accurateshooter.com/cartridge-guides/308win/

Thank you that was a great read..

 

[Homerange]

Gona load some 150gr fmj for my .308 win for the first time useing IMR 4064. Looking in the hornady 9th edition it shows 38.4 start and 44.9 max. But the Speer manual #14 shows 43 start and 47c for max. That's a lot of diffence. Why is so one so much hotter than the other?

Iam just trying to find a mid power load to start with and that is very confusing. Just trying to check on the accuracy of an old Remington and got tired of buying factory ammo. Mid power in one book isn't even start in the other. Also if anyone would leave a nice shooting recipe for 150 gr fmj and IMR 4064 in .308 win. to compare? Its what powder I have right now.

This is a good example why to NEVER throw out any reloading data, no matter how old it is.

From 45th Edition Lyman Reloading handbook (40 years old)
308 Win. Win cases
150gr jacketed.
IMR 4064
Starting: 43gr 2645 fps 41100 CUP. Max: 48gr 2890 fps 52000 CUP

Note: This load is asterisked as a Factory duplication load.

Over the years we have seen a lot of CYA loads printed, some to compensate for variances in powder batches but most IMHO are now lower charges to save us from ourselves.

 

[Rsadams]

This is a good example why to NEVER throw out any reloading data, no matter how old it is.

From 45th Edition Lyman Reloading handbook (40 years old)
308 Win. Win cases
150gr jacketed.
IMR 4064
Starting: 43gr 2645 fps 41100 CUP. Max: 48gr 2890 fps 52000 CUP

Note: This load is asterisked as a Factory duplication load.

Over the years we have seen a lot of CYA loads printed, some to compensate for variances in powder batches but most IMHO are now lower charges to save us from ourselves.

When I read your post it reminded me that I have a lyman 49th edition. I dug it out and sure enough it shows 43 to 48 also. That's 5 different sources that list the 43 gr as a starting charge so I guess the hornady data is just CYA data as you stated..

The only difference I see is in coal most are 2.800 and some 2.700 does anyone think thight might raise the pressure enough for the way low hornady data? Doesn't seem like it should..

 

[DRNewcomb]

I just can't get over the spread in charge weights between the 2 books....

Even if the two companies use essentially the same standardized test barrels, variations in primers, brass and bullets can account for a lot of differences. Also, while the power manufacturers strive to achieve lot-to-lot consistency, there are differences between lots of the same powder. There is also the issue that one company might be a tad more conservative than another.

If you aren't an experienced reloader, I'd suggest picking a charge covered by the spread of the two books. There's plenty of safety margin with published loads.

 

[SheepDog]

The Hornady information was developed with the Hornady bullets and the Speer data was put together with the Speer bullets. The bullets are of different construction so even though the weight is the same there is a difference in powder capacity.
This is precisely why it is recommended to use the data for the components you are using.There are differences in cases and bullets that define the load range. Be safe and use the same components listed for the load work-up or reduce the load and develop it on your own which can lead to mistakes.

 

[Homerange]

The Hornady information was developed with the Hornady bullets and the Speer data was put together with the Speer bullets. The bullets are of different construction so even though the weight is the same there is a difference in powder capacity.
This is precisely why it is recommended to use the data for the components you are using.There are differences in cases and bullets that define the load range. Be safe and use the same components listed for the load work-up or reduce the load and develop it on your own which can lead to mistakes.

Exactly.
One must look at the listed loads somewhat carefully to determine the projectile style used. Now we have the added complexity of homogamous bullets, boat tails and flat bases one needs to be careful not to substitute these at random.
Pull the max load back some and work up slowly watching for signs of pressure, better still use a crony while doing so and watch for loads that might exceed velocities that are listed for any load.....until you are confidant and can safely start to push the limits of printed data.
No point trying to reinvent the wheel pushing velocities to the point where the loads become unpredictable. Some calibers have reputations for not liking to be pushed too hard.

Be careful out there.

And about COAL. I always try to load a long as possible but in most cases mag length will determine max COAL before you hint the lands. But always good to know where the lands are for each projectile in your rifle. You need to measure each and document it.

 

[Rsadams]

Exactly.
One must look at the listed loads somewhat carefully to determine the projectile style used. Now we have the added complexity of homogamous bullets, boat tails and flat bases one needs to be careful not to substitute these at random.
Pull the max load back some and work up slowly watching for signs of pressure, better still use a crony while doing so and watch for loads that might exceed velocities that are listed for any load.....until you are confidant and can safely start to push the limits of printed data.
No point trying to reinvent the wheel pushing velocities to the point where the loads become unpredictable. Some calibers have reputations for not liking to be pushed too hard.

Be careful out there.

And about COAL. I always try to load a long as possible but in most cases mag length will determine max COAL before you hint the lands. But always good to know where the lands are for each projectile in your rifle. You need to measure each and document it.

Yes, I have decided to buy 1 more box of factory and get some crono readings with it before I start reloading for it. Instead of going in blind. This is for an old Remington 788 and hot charges are not what iam looking for for it. If anything I will take a little off. Iam just trying to judge the accuracy of it at 100 and am tired of buying factory ammo for it. All the work iam going to do is now done. New leupold etc.

So I will wait and put another box of factory through it and judge both the accuracy and baseline crono data first. Then try some reloads in it.. It will be a range toy and or a backup to a backup for a hunting rifle..

Thanks for your time...

 

[Homerange]

Yes, I have decided to buy 1 more box of factory and get some crono readings with it before I start reloading for it. Instead of going in blind. This is for an old Remington 788 and hot charges are not what iam looking for for it. If anything I will take a little off. Iam just trying to judge the accuracy of it at 100 and am tired of buying factory ammo for it. All the work iam going to do is now done. New leupold etc.

So I will wait and put another box of factory through it and judge both the accuracy and baseline crono data first. Then try some reloads in it.. It will be a range toy and or a backup to a backup for a hunting rifle..

Thanks for your time...

About your 788, I've got a 770 in 7mm08 and another 308 and they are pretty easy to load for.
My 770 prints under 1/2" groups with reloads and under 1" with factory.
I mentioned some problem I had when I first got it here:
http://forum.accurateshooter.com/threads/remington-788-torque.3922074/#post-36945022