338 Norma Magnum

[Sling]

Anyone running one? I just finished my build and trying to get some loading data. I`m going to run 300gr Bergers. I read that Jimmy Sloan designed the cartridge and he recommends Ramshot Magnum powder but I don`t want to use ball powder as this gun will be used year round. Seems Ramshot is very temp sensitive. I`ll probably try some Retumbo & Vihtavuori N-570.

Thanks

 

[338 Mollett]

I have 5 years testing with various 338's including 338 norma.It's hard to condense all that to help someone in one or two questions ,But I'll help all I can. The norma is much more reliable and repeatable than the 338 lapua.The norma is 100 fps slower than the lapua in 250 and 300 g bullets.High bc bullets need the velocity to gain the full benefit of the bc. In my opinion 300g is too much for the norma or the lapua.The 250 scenar proved most accurate in the lapua, norma and my cartridge. H 4831, N 165 and h 1000,were the most reliable powders .N 165 gave 2900 fps with the 250 scenar and groups in the 2 to 3 inch range at 800 yds, though temp sensitive.5 thou. clearance on the necks.Scenars liked a 15 thou. jump.Which were compatible in jump with smk but I felt I didn't have to sort as much.As with any case there is a cost for hot loading these cases.Especially depending on your action.If you want to go bc crazy try gs bullets, nothing will fly with them. Not as accurate as jacketed bullets but the most accurate lathe turned bullet I tested.Ask away I'll break open the test logs to help,they're gathering dust any way ! ;D

 

[Sling]

Thanks. My friend has a 338 Norma with 28" barrel getting 2805fps with 300gr Bergers. I have chrono quite a few 338 Lapua`s with 30" barrels with 300gr bullets and they were all around 2840-2850fps. I have some very nice places close to home to shoot out to around 2700yds. Thats the reason I don`t shoot 250gr bullets in 338`s.

 

[338 Mollett]

Your friends load getting 2800 is a very hot load.I had to make a small base die due to hot loads like that.A 300g berger goes subsonic close to 2000 yds I can't see a practical reason to stretch to 2700 other than poops and giggles,but don't get me wrong that has been a good reason for me on many thing lol!The gs bullet weighs 232g with a bc around .8 and can be driven to 3050 comfortably.This out fly's the berger at 2000 yds.The berger needs about 77 moa from 100 to 2000 I hope you have the adjustment.The gs bullet about 64 moa.If you want to take a few pot shots at long range I think you're gonna have fun, I was looking for the ultimate f class cartridge, don't go that route.For speed re 25 gave the best velocity but was dirty and unreliable .Good luck!

 

[Sling]

It`s not a hot load. We have shot the same brass around 5 times each and primer pocket is still tight and the webb hasn`t grown over spec. He is using a Redding Type S full-length sizer and it chambers smoothly after sizing being shot that many times. You mention subsonic, I have shot the 338 Lapua out to 2449yds (300gr) with great accuracy. Some people say it isn`t possible but its true. I know of another shooter who has shot his Lapua (300gr) out to (if memory serves me correctly) 2662yds. I was his spotter and every shot was within arms reach of a target the size of a upper torso. I call that accurate. Certain bullets can handle subsonic velocities better than others.

 

[xdeano]

I'm actually in the process of load workup on the 338NM also. I've only shot a few test rounds through the rifle. I'm using the 300grn Berger with 91.5grn RSM and getting 2738fps with a 26" barrel. The 92.0grn RSM was getting 2838fps no sticky bolt, no pressure signs at all.

xdeano