Changes to Vihtavuori Data

[snowstorm]

I have noted the newly released 2008 reloading data on the lapua web site for Vihtavuori powders.

Until now I was using the 2006 data which had a load range of 34.3 gr to 38.3 gr for a 243.

The 2008 data has upped this range to 35.2 gr to 40.1 gr.

Does this seem like a large increase?

It might explain some of my recent shoulder marks when testing loads up to 37 gr.

 

[DaveK]

Have I missed something? Apologies if I have but which Viht and what size bullet please?

I use n-140 with 75gn Vmax and load it with 41.2gn

Can't remember off hand but with n-160 and 95gn SST its either 44gn or 46gn I use (or thereabouts).

 

[snowstorm]

Hi,

Sorry, the burn mark thing was from another thread.

The heads are 87 gr and its N140 powder

The new data is on the web site now, but was a max load of 38.3 which they have now increased to 40.1.



Regards

 

[Offroad Gary]

i've noticed this too and am currently working up some 85gn loads in .243 and 125gn ballistic tips in .308.

37.3 gn n140 is sierras "accuracy load" for their hpbt 85gn load, indicated as max for this bullet.

 

[snowstorm]

Bucksden, what has your listed maximum powder load increased by with the new data?

Nearly 2 grains for me with the 243 seems a lot.

I wondered whether I should email them and check it wasn't an error?

 

[Offroad Gary]

Bucksden, what has your listed maximum powder load increased by with the new data?

same as yours i'm looking at the current online manual, but i was given a hard copy of older manual the other day when i was in reloading sollutions. that has the lower figure as max.

i'm not an expert by any means, only been loading a couple of weeks but i'm sure if you start low and work up you will notice pressure signs when they start to appear.

 

[snowstorm]

Same here, was first lot of loads I ever made up.

If you search for a thread from me a week or so ago you'll see that I was getting low pressure signs right up to 37.3.

But the jury was out as to whether this was due to it being new brass.

I've just neck sized the next batch which have now been fired and I'll start from the new higher figure listed, and see how that affects things.

 

[JAYB]

snowstorm, would it not be better just to increase your last maximum load by 0.5 of a grain increments until you reach what is the optimum load for your rifle. You may miss the sweet spot by jumping straight in the deep end

John

 

[snowstorm]

Hi JAYB

Yes, I'd meant the new higher starting load figure. I could keep going from 37.5 which was where I left off last time, but now I have once fired neck sized brass to work with so I'll start over from scratch.

Cheers.