Manuals

[jpbaker]

I had a bunch of SST 165gr to load in .300wm.

When I sat down to do some today, I open my manual to check (never loaded these in my .300wm.)

I have Vargent, H4895, and H4831sc on hand.

I checked my:

Hornady book (7th ED)
Lee Modern reloading (1st ED)
Lee Modern reloading (2nd ED)

I noticed LEE 1st ed, max for H4831 was 78gr, but with second edition the max is 75.5 grs. (jacketed)

Why such a large difference between manuals.

I always start low and work up, but I am just wondering what the deal is.
The test rifle specs are not mentioned, so there is nothing to compare there.

This may be a stupid question, but plz humor me . Im fairly new to this!!!!gun)

 

[boomtube]

"Why such a large difference between manuals. I always start low and work up, but I am just wondering what the deal is."

The deal is, all rifles are a law unto themselves and the book makers used different rifles; your's adds a third variable. If all rifles were the same there would be no need or benefit to 'start low and work up.', we could just skip the work up and use the hottest suggestion but in the real world that would be dumm.

 

[TOM H]

I had a bunch of SST 165gr to load in .300wm.

When I sat down to do some today, I open my manual to check (never loaded these in my .300wm.)

I have Vargent, H4895, and H4831sc on hand.

I checked my:

Hornady book (7th ED)
Lee Modern reloading (1st ED)
Lee Modern reloading (2nd ED)

I noticed LEE 1st ed, max for H4831 was 78gr, but with second edition the max is 75.5 grs. (jacketed)

Why such a large difference between manuals.

I always start low and work up, but I am just wondering what the deal is.
The test rifle specs are not mentioned, so there is nothing to compare there.

This may be a stupid question, but plz humor me . Im fairly new to this!!!!gun)

If you see a difference it normally means they retested that load. One good thing about Hodgdon(IMR/Win) powders they have data on-line.
Basic Manual Download

If you look at Hodgdon data 2011 they list start load for 300Win with 165gr SPR Sp @ 72gr/H-4831 and Max load 75.5gr /H-4831.

Alliant powder and others also have loading data on line and you can get data from Sierra etc.

 

[Browninglover1]

Did the Lee manual have actual data for the SST or just a 165 grain load? Different bullets can affect pressure quite a bit based on things like bearing surface and jacket thickess.

One example is the Nosler Partition. It traditionally builds higher pressure than other bullets of the same weight and so its listed max charge is often a little lower than other bullets of the same weight.

 

[Zep]

It is my understanding the powder manufactures do make changes to the powders over time. It may be over many years or even considerably less a period of time. This is why it is extremely important to use the latest loading data. It is extremely important to contact the manufacture if you have any questions and it is also extremely important to make sure you get answers you understand.

I shoot a lot and I talk to a lot of shooters. To date I have personally spoken to two men who have blown up guns and they both thought they did everything correctly. Luckily neither was hurt but frankly I think they were both very lucky.

--

And Browninglover1 is correct, a lot of load data is bullet specific.

This is a good thread, I hope it continues.

 

[boomtube]

"The deal is, all rifles are a law unto themselves and the book makers used different rifles;"

Supposed "changes" in a manual's suggested powder or powder lot, OAL, differences in bullet design and composition, etc. are true but the effects are highly exagerated. Fact is, there is no change we can make in any book load that has an effect anywhere nearly as great as the weapon it will be fired in, the rest is trivia.