338 Lapua Improved data. 300 SMK

[Rhovee]

I had @Alex Wheeler build this 33 Lapua Improved for me a few months back. Specs

Bat HR
Bartlein medium palma 26" 1-10 twist
Manners LRH stock
SRS muzzle break
Bix N Andy trigger.
NF 7-35x56

Alex has quite a bit of experience/research with this round. We went with 300 SMK so we could use the new Unknown Munitions 3.950 DBM and still be in the neck with a 300 SMK. We have seen the SMK shoot good from 5-15 off. 102.5-103 grains of N570 has been the norm from previous rifles Alex has shot. I started there and didn't have to go far. When I got the load as dialed as I could, I still felt there was more to try. I hadn't shot those "screamers" that my edge has. This weekend I tried Fed215 VS CCI 250. And light verse heavy neck tension. Fed 215 was a great switch with an SD of 4 and a 1.01" group at 600. 92.5 was still 1/2 moa and the triangle shape of the group is a good sign. 2900 fps with 300 SMK in a 26" is a mean dude!

 

[C.O. Shooter]

Solid!

 

[Lonewolf74]

How do you like the Unknown Munitions mag and bottom metal setup?

I wish that it or the MTD 4" mag and PT&G 4"bottom metal was available when I was putting my big 338 together and I probably would of went Lapua improved instead of Norma improved.

Where do you think you would top out for velocity with the 300 SMK?

 

[Rhovee]

The mag is working great. I did a little tweaking to the feed lips to feed best for the AI version. I honestly haven't reached pressure, because I knew with N570 I was pretty full with 103 grains and wouldn't reach another node around 3 grains more. I did go up to 104 with no issues for 2950.

 

[jfswanson12]

I know this is old but what do you like to fire form with load wise? I have a lot of bullets, and h1000, return, 570 etc. Alex spun mine up for the 300 bergers long term. Thanks

 

[Rhovee]

I would form with H1000. I can check notes, but 90 grains H1000 is what I would use. Jam the bullets .020-.030.