.338 Norma Magum

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If anyone’s interested, here are the results following a recent OCW at 100m with two powders; RAMSHOT Magnum and RS80.

Load spec for all bullets;

New .338 Norma Magnum brass 

300gn Lapua Scenar coated with HbN (bore also HbN swabbed)

Fed 215GM magnum primers

Boat tail seated right at neck-shoulder junction, which is around 0.01” off the lands and leaves around 0.05” space in a standard AICS .338 magazine. Full magazine feeds perfectly - smooth as butter!

Summary is that RS80 definitely produced better groups AND more consistent ES & SD. RAMSHOT magnum produced some ok-ish groups but poor ES & SD. Both powders a bit sooty, RAMSHOT mag being the worst of the two.

None of the loads showed any signs of pressure; primers and case extraction all fine. All loads pleasant to shoot, the Area419 brake doing an amazing job. I could shoot this thing all day 😋

Interestingly this .338 barrel is shooting almost exactly 1MIL low and 1.2MIL to the Left compared to my 6.5x47 barrel. But switching between the two barrels shows no discernible change in POI. I also credit the Era-Tac QD mounts too ...no shift in POI taking the scope on and off.

EDIT: forgot to say this was a virgin barrel, so all OCW was in fact barrel break in...no cleaning between. Dry patching afterwards was sooty and took about 5 patches before running clear-ish.

1st up the RAMSHOT mag. After some wild shots top left to get me on paper, the groups came. I struggled to keep the Magneto speed fixed and capturing good results as the muzzle blast was significant, but I’ve written down what I got.

Next up up was the RS80. I think a great node is around 94.0gn, as either side has low vertical, ES & SD. 

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Best group of the day (yup that’s 5x in there!), 93.0gn RS80;

Optimum OCW I think with low vertical, ES & SD. I think the group opened up a bit due to me...I know I should have done better here. 94.0gn RS80;

Also nice node with low vertical & SD, 94.5gn RS80;

 

I know I could push the 300gn Scenars a bit faster, probably another 2gns and breaking 2800fps, but I’m happy with the results. It’s very pleasant to shoot and the bullets will enter the transonic range at around 1500m which is fine.

[Popsbengo]

Nice!

What's your barrel spec?

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Barrel is a 27” Bartlein 5r, 1-9.3” twist, to a contour of my own spec; 1.35” at the chamber, straight for 5”, straight taper to 1.2” at muzzle. Chunky as hell but does an awesome job of soaking up the recoil. 

Although this is a switch barrel gun, it’s just too much fun in .338NM guise, so I think it’ll mostly stay as it is for a while 😁👍

[Popsbengo]

That's a fluffing nice gun mate!

I have a 32" Truflight 1:10 and that's pushing .338LM 300gn Scenars to 2850 fps with 92gn Viht N570.  A nice clean burn.

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Thanks Pops.

Sounds like a great setup yourself. That is a very healthy speed to be slinging those big long pills. 👌

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Actually, looking back at some the uncleaned brass it was only the lower loads that were sooty. The higher loads were cleaner burning, just a smidge of carbon on the necks. 

My take is that the beyond 92.0gn of RS80 it was fairly clean. The RAMSHOT mag was definitely not as clean. That’s good news to me as it’s a real PITA to load with ball powder, the extruded is so much better.

[No i deer]

It's definately worth trying the 94.5gr load again,that one shot to the left was more than likely you.

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17 hours ago, No i deer said:

It's definately worth trying the 94.5gr load again,that one shot to the left was more than likely you.

Yeah I probably will. I do remember both 93.0g and 94.5g being particularly nice recoil impulses. I dunno what it was but both those loads definitely felt very comfortable to shoot. 

[No i deer]

Yes 93grs was a great group but very similar at 94.5grs,you need all the velocity you can get from the 300gr scenars to get the best out of them for ELR ,the scenars are great bullets. Are you pointing them for the extra BC...?

I'm not familiar with the 300 grainers only 6.5 and 7mm ones.

How consistant do the measure and weigh,the ones I use are as consistant as anything else I've used.

I have shot the 300gr scenars in a mates 338 lap mag.they were great out too 1800yds.

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20 hours ago, No i deer said:

Yes 93grs was a great group but very similar at 94.5grs,you need all the velocity you can get from the 300gr scenars to get the best out of them for ELR ,the scenars are great bullets. Are you pointing them for the extra BC...?

I'm not familiar with the 300 grainers only 6.5 and 7mm ones.

How consistant do the measure and weigh,the ones I use are as consistant as anything else I've used.

I have shot the 300gr scenars in a mates 338 lap mag.they were great out too 1800yds.

No I’m not pointing them...makes very little gain for a lot of effort based on what I’ve read.

Measuring 5x random bullets from the same box, I got these numbers;

Weight = max 0.4gn (average was 0.2gn)

Length (to Ogive) = max 0.05” (most were 0.02”)

Fairly consistent for such a large/heavy bullet I think, especially as they’re actually very good value for money. Sure it’s not a Berger...but it’s no where near the price of a Berger either. I’m happy sticking with the Scenars.

I managed to find time to load another 100x this morning. Note the ‘fairy dust’ on the bullets. It shall be interesting to see how the barrel holds up over time. 

I must say that I’m well smitten with the .338NM . Before choosing the calibre I had read a lot of people found its inherently very accurate and very easy to tune. So far I’ve definitely found it is so, just dump the powder and go shoot. I’m not even going to bother altering seating depth. 

[No i deer]

The 300gr Bergers won't measure and weigh any better, the scenars may benefit from pointing as they have got a big meplat compared to the Bergers. The 285gr ELD's got the ballistic tip and they have the biggest BC but are they as consistant and the Bergers and scenars....?

Probaly not and they would be that bit longer and may not fit the mag.

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I’ve got some 285 ELDs...I’ll measure up tomorrow. But at nearly twice the price as the Scenars, I won’t be feeding this gun many of them. Availability is also patchy. 

[No i deer]

I can invisage the bigger the bullet bigger the meplat,Bergers are Gucci and a good wind call would be better,scenars are IMHO very good.