Originally Posted by Fiftydriver
Just wondering if the 338 Norma Mag cases are stronger then that companies version of the Lapua Magnum?
I used some of the Norma 338 Lapua cases early on in my development of my 7mm, 300, and 338 and found them to be about the same strength as a Remington RUM case. With my improved case design I was able to get around 100 fps over the RUM chamberings in same caliber but the primer pockets let loose rather rapidly.
Switched to the Lapua cases, gained another 75 to 100 fps over the RUMs and I have yet to loosen a primer pocket to date.
Just wondering if they have improved the head strength of their new 338 Norma Mag case. I assume so since you chose that over the Lapua. I was always impressed with the quality of the Norma cases, just which they would take the top end pressures better. Maybe that has been corrected.
Hell of a rifle by the way.
Here are my findings so far.
I weighed a bunch and measured neck thickness. They were super consistent..very happy.
flash holes had no burrs inside
primer pocket depth was pretty good. The base of the case is designed different than the Lapua although it is the same dia. the Lapua shell holder will not work due to the diameter being larger in the extraction groove. also the extraction groove is narrower than the Lapua making this case 'beefier' than the lapua.
I only have 5 reloads on a single case so far but, no sign of loosening primer pockets. My goal was 3200FPS with 210's and it has easily met this with the Retumbo.
Pressures are a little high with the H-1000 at 3200FPS. There is plenty of room in the case even with 92 gr. of Retumbo, There is a little space between base of bullet and powder.
This case was definitely designed for pressure. I'm not one to push things to the limit so I am quite fond of Norma brass. If loaded to decent pressures, it seems to be very good as far as necks cracking and longevity.
I have the reamer and sizing reamer for the .284 JAZZ. hopefully will be testing one of these in the near future. I have 1000 pc. of Norma brass and will be offering it with builds.
I have been working on designing these chamberings since last summer and it is pretty exciting to finally be getting some results. I have a few pix of some groups and will try to get them on in a few days.