Need help with 300gr bergers in 338 Lapua

[Roll-Yur-Own]

Hi All, I've been loading 300 SMKs in my 338 Lapua using 94 grains of retumbo. 94 grains is hodgdon's max load. However, Berger lists max load of their 300 grainers at 89.5 grains. I check Nosler's sight for the 300AB and they also use 94 grains.

I load to 3.60" so they fit in my magazine. (My loads shoot 1/4" so I never worried about loading longer) I did see the Berger uses 3.68 in their data so I wondered if they lower the charge for pressure reasons but Nosler uses 3.65 so I figured that can't be it.

Anyway, is berger just way to low or is there something I'm missing.


Thanks in advance to all who reply.

Roll-Yur-Own

 

[el matador]

Bergers are pretty long so they would have to be loaded deeper to get the same OAL as a shorter bullet. Seating bullets into the lands will raise pressure so maybe Berger is allowing for that. Also published data is only a guideline for working up your own loads in your own gun. I've seen some pretty big disparities between manuals before. The best thing to do is look at a bunch of data, start 5-10% below the published max and work up until you find your load or see pressure signs.

 

[snowpro440]

Bergers are pretty long so they would have to be loaded deeper to get the same OAL as a shorter bullet. Seating bullets into the lands will raise pressure so maybe Berger is allowing for that. Also published data is only a guideline for working up your own loads in your own gun. I've seen some pretty big disparities between manuals before. The best thing to do is look at a bunch of data, start 5-10% below the published max and work up until you find your load or see pressure signs.

Actually the opposite is true El Matador

 

[sp6x6]

Id say they are low,but for there reasons as safety as most say. I am shooting the smaller capacity 338 NM and my load is 87.5 retumbo and my COAL is 3.670. I have taken it too 91 with slight bolt lift. This load is .005 off in my rifles,one is about .001 diff. and also fits the one that is AI mag fed.

 

[barefooter56]

Roll-yur-own,
Our load data is rather conservative and it is not uncommon to exceed our maximum
loads on occasion. Having said that ALWAYS TEST AT THE LOWEST POWDER CHARGE LISTED TO FIND YOUR SEATING DEPTH SWEET SPOT. Cartridge pressures do increase after a certain point when seating a bullet deeper in the cartridge case as they do after a certain point when working out to the lands. So there is a certain area between these two where the pressure are rather stable. The seating depth /pressure issue can happen fast especially with our long VLD bullets which is why we are so conservative.. Hope this helps!
Take care,
Phil Hoham
Berger Bullet Tech