Why is load data different in different manuals?

New Avon Arms

Mr8

Member
Hi all,

I have a new build Enfield No.4 MK2 with a Lothar Walther barrel that I've been reloading for and have been using a manual that was written specifically for reloading 303 British written by Stephen Redgewell. I've found that my Rifle groups a lot better when I've loaded my rounds with the maximum amount of grains of N140 as stated in the book and has no signs of overpressure on the primers or brass and the bolt feels fine after firing. My only concern is that I've been looking through my Lee reloading manual and the maximum load it says never to exceed is 2.5 grains under what my other manual states.

I'm not sure now if I should now back the grains back down to The max load the lee book says at a slight cost of accuracy or if I should just continue reloading as I was before and keep an eye out for pressure signs.

All advice is appreciated and obviously I know I will take any advice at my own risk.

Many Thanks,
Mr8
 

Crowstalker

Well-Known Member
I can't explain why there is a difference it if there is no over pressure signs or anything like that I would be happy to stick with the load you are using
 

Alantoo

Well-Known Member
When were the two manuals you are comparing published?

The Vihtvuouri site would be the best place for the current N140, they will be most up to date.

Alan
 

Namman

Well-Known Member
When were the two manuals you are comparing published?

The Vihtvuouri site would be the best place for the current N140, they will be most up to date.

Alan
There have always been these differences in reloading manuals. Components vary, some data sources eg Speer use their own brand of bullets, others like Lee give a generic jacketed bullet weight and / or style. Cases vary, as do makes of primers and also different batches of powder.
Hence the advice to start with the starting load and work up watching for signs of excessive pressure.
 

Mr8

Member
Thanks guys, I'll have a look on the viht site for their load data.

Would any of you ever gradually build up to a load over the max in the manuals whilst keeping an eye out for excessive pressure?
 

Ttocs

Well-Known Member
Reloading rule 1, always work up a load for a new barrel/rifle even when using the same components. It’s exactly the same for the authors of the reloading manuals, whilst they may be using the same powder, billet, case and primer, they’re not all using the same barrel/rifle so get different results. They may not all apply the same safety/litigation margin at the max either!
N
 

Mr8

Member
Thanks for all the advice, just had a look at the viht website and their load data is the same as it is in the Lee manual so I might get the ones I've been making using the load from the Stephen Redgewell manual proofed just in case because they do seem to shoot so much more accurately.
 

Foxyboy43

Well-Known Member
Good idea - especially if you are that far above max in both Lee and Viht guides. Over recent years there has been much "downwards adjustment" in loads data much of it down, sadly, to the litigious society we, and especially America have become. You might well find that if you use the Viht data and start low you may well find a recipe that is accurate and well within their prescribed limit. Good luck.
 
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