6.5-284 Norma + Scenar 136-L + H4831sc Load Verification

[Sawacs]

Would you guys mind giving me a math check on my load data?

I am trying to figure out a safe starting load for my 6.5-284 Norma 24" CBI 1/8 twist barrel using the Lapua 136-L Scenar bullets and am having a hard time.

Maybe I am overly cautious but I have no desire to blow myself up

Here is the situation..

My particular chamber will allow me to seat the 136's to 3.068 COAL which is touching the lands.

Lapua's data shows a COAL with the 136's of 3.110"

Berger sent me data for the 136's with a COAL of 3.180" which I cannot achieve due to a shorter throat.

Here is the data from Berger for the Lapua 136-L's using H4831sc which is also the powder I am using.

Bullet: Scenar 136-L
Powder: H4831sc
COAL:3.180"
Start charge: 49.0gr 2657fps
Max Charge:54.2gr 2936fps

Just for reference, Nosler shows the following data for a 140 grain bullet

Powder: H4831sc
COAL: 2.980"
Start charge: 45.0gr 2601fps
Max charge:49.0gr 2769fps

My delima is where to start with the charges if my seating depth is 3.048" COAL or .020 off the lands?

Would I be on the safe side starting with 47.0gr of 4831sc based on a seating COAL of 3.048"? Hornady lists a max load of 4831 with their 140 Amax seated to a COAL of 2.880" as 45.9gr.

Advice would be appreciated!

 

[XTREM HTR16]

My hunting pard was getting 3,075 with the 130 accubond and R23, if you have any R23 it seems like a great powder for the 6.5x284.

 

[Sawacs]

Thanks for the reply.

I am trying to figure out if I would be on the safe side starting at 48.0gr of H4831sc over a 136-L Scenar bullet.

Another way of looking at it would be how much of a pressure increase will I get by seating the 136-L @3.058" (.010 off the lands) rather than Berger's 3.180" COAL which is what the data they sent me is based on.

After looking at Nosler's data and the data Berger sent me again, I am going to make starting loads of 48.0gr,48.5gr,49.0gr and 49.5 over H4831sc @3.058" COAL with two rounds each and see what happens