Reloading Manual Differences

M

M14CheatOtoole

New member
Rating - 100%
6   0   0
I am new to reloading and have been using the Speer manual that came with my reloading kit.
I have just loaded up some .308 168 gr BTHPs using the data found in the manual for this particular bullet. I started with 42 gr of Varget and increased to 44 gr of Varget in 0.5 gr increments loading 10 rounds of each. The purpose being to try to narrow down a range that my rifle likes and then start in with 0.1 gr increments.
The Speer manual states 42 gr of Varget as the starting load with 46 gr of Varget as the max load.
I was searching around on the internet and found a copy of the Sierra manual for .308. It states 43.8 gr of Varget as the max load for 168 gr BTHP.

What's up? are Speer .308 168 gr BTHPs that different from Sierra .308 168 gr BTHP or are they interchangeable?

Some information / advise here would be very much appreciated. I know I should buy a few different reloading manuals.

Thanks in advance.
 
All of the manuals contain different data,because different rifles were used to test the loads to arrive at the data in each manual.To top it off,none of the rifles used by the people producing the manuals were your particular rifle,so none of the data in any of those manuals is necessarily any more correct for your rifle,than the data in any of the other manuals.Any maximum load listed in any manual,is not necessarily going to be safe in your rifle.
 
It is usually wise to pick up two or three good manuals and cross check loads. Use a good measure of common sense and slowly work up your loads. The heaviest/fastest loads typically aren't the most accurate! Once you start approaching max loads, keep an eye out for pierced/flattened primers and sticky bolt lifts. If you start experiencing this, back your loads off as they're too hot.
 
I found the best bet is to pick up a copy of the loadbooks manual for your specific caliber. It has caliber specific load data from all the manuals condensed into one book, making crosschecking, and building new loads easier.
 
An assortment of manuals is good, as has already been pointed out, and Hodgdon's is free on line. In that connection, you can, with a bit of googling, find other free online manuals and a burn rate chart that'll give you a reference for when you don't have a manual for the exact powder you're checking out. I say checking out because if you're going to load a cartridge, you do want a solid reference to work from not an estimated one. Anyhow, this is just to say there are free sources you can find and use until your library is properly fleshed out. Have fun.
 
Another reason to own a number of manuals is that each manual comes to the data in a slightly different way. Manual "A" will give the maximum load with a corresponding velocity while manual "B" gives a maximum velocity with the corresponding load. These are not necessarily the same. Some manuals come with a better selection of powders than others, some come with more cartridge listings than others, and some have mistakes in their data.
 
M14CheatOtoole said:
What's up? are Speer .308 168 gr BTHPs that different from Sierra .308 168 gr BTHP or are they interchangeable?
Click to expand...

Different bullets of the same weight may result in different peak pressures for several reasons: shape; core hardness; jacket material; jacket thickness; length of bearing surface.

Apart from the bullets themselves, there are also variables in rifle chambers and bores, brass dimensions, differences between lots within the same powder, etc., etc.
 
Last edited:
You must log in or register to reply here.
Back
Top Bottom