Help with 338 lapua improved load data.

[njones125]

So i finally got all my brass fireformed for the .338 Lapua improved 40 deg. This is my first custom and I cant find any load data for it. I have 2 different loads that were shooting great during fireforming (one with Retumbo & one with US869) . Is there a % that I can safely increase powder based off of a standard lapua load? Any input is appreciated.

 

[RockyMtnMT]

You can look at load data for the 338 lapua and use max load data for start load. RL33 is good for the heavies and H1000 and Retumbo good for mid weight to light bullets.

Steve

 

[Jakeleg]

In my Rbros imp. Lapua I'm running N570 with the 300 bergers and have good luck. But I'm tagging in for new loads also. Would like to try some flatlines.

 

[B23]

In my 338 Lapua Imp. and 30-338 Lapua Imp. I use US869 with the 300's and the 230's but RL33 and N570 are both good choices as well. I think N570 is quite a bit harder on throats than the others though.

My experience using US869 has been positive and I get very good ES #'s with it but I've found it's a powder that needs the bullets loaded very close to touching because the further I back them off the higher my ES numbers typically get.

 

[Tyler Kemp]

I shoot 100gr Retumbo behind 300gr Matchkings, Bergers, and 285gr Hornady ELD.

The Sierra and Hornady are about 3050 fps, Bergers 3020 fps. 32" Broughton barrel. 104gr is where I see pressure.

 

[JeffVN]

I concur with some of the voices above. Mine likes V.V. 570 & RL-33 equally for the 300s, it just take a touch more RL-33 to hit the same node.

Jeffvn

 

[embork]

In my 338 Lapua Rogue 37 Degree shoulder 99 gr of Vhnt 570 3000 fps with 32 inch Barrel. that's with 300 gr Berger

 

[Tyler Kemp]

edit: wrong post