Reloading 338 Lapua Magnum

M

Machineguntony

New member
I’m getting into shooting 338 LM.

Anyone have experience reloading this round? Any advice on reloading it?

I’m thinking of getting a single stage just for this round. All my current loading is done on Dillon 1050 and 650s.

I heard the 338 LM isn’t known for MOA accuracy, so should I just stick to reloading it on the progressive? I do want to have very accurate powder measurement, so if I do load it on a progressive, I’ll probably still use an electronic powder dispenser. The Dillon progressive dispenser is not very accurate.

Last question...the 338 Lapua Magnum uses the same 338 bullet as every other 338 large rifle round, correct?
 
When in doubt on dimensions, your first step is to download the SAAMI drawings file and look it up. Same as a 338 Federal or a 338 Win Mag, the bullet tolerance is 0.336-0.339, with .338 being the nominal groove diameter and preferred bullet diameter.

I do not own a rifle in this chambering, but I would imagine most accuracy complaints about it have to do with not tuning the rifle or its loads properly. The 338 LM was developed as a military long-range sniper cartridge, so it has to be possible to shoot it at least fairly well. I'm not much of one to put too much faith in notions of "intrinsic accuracy", as long as the barrel rifling twist isn't way off for the bullet chosen. The .270 Winchester was never popular for accuracy matches, but Harold Vaughn got a modified sporter to shoot 1/4 moa. So have faith and expect to put a bit of work into getting it to shoot. That's part of the fun, anyway.
 
The one article I saw by someone who I thought knew his stuff was definitely sub MOA, more like sub half MOA.

He had a Sako TR-42 (?) and great optics so the equipment was first class.

If I was going that route I would get the Savage Target 338 with the Target Acu Trigger (down to 6 oz or so).

I would shoot the barrel as a learning tool, it might well be a good sub 5/8, it might be better. At some point the barrel is gone and then you get an aftermarket pre fit for under $400.

I would go with Shilen or Criterion if I am just an average target shooter (I am) if I was in David Tubbs shadow (I am so far I want to cry) I would go with a cut rifled Lilja, Bartlein and a few other cut rifled types.
 
Probably best advise i can give is to pick a powder that gets you close to 100% case fill.
You don't want a lot of air space in some of the large case magnums.

Steer clear of RL25. Velocities are there, but dismal accuracy.
 
What’s everyone favorite power for the 338 LM?

I’ve already bought the gun and the silencer.

Now to assemble to components, dies, powder dispenser, and single stage press for bullet seating, since I do trust my progressives to accurately seat a bullet. I’ll use the progressives to process the brass and seat the primer, though.
 
I use the 300 gr scenar or 300 gr smk. 90-91 gr Retumbo. Lapua brass, CCI 250 primers.

2880-2900 fps depending on weather conditions. 3/4 MOA at 600 yards avg .

1 MOA avg @ 1k yards & 1,200 yards.

Armalite rifle w/ nightforce nxs 8x32, 27" barrel


I mostly just stick with the smk since scenars are more expensive and I found no real difference in performance.

I couldn't get VLD bullets to group well when I was doing load development for my 338 LM, but there are better options today then there were in 2013 when I was shooting mine a lot. I still pull it out and ring steel once a year or so with it, and I have found no reason to change the load since I just do recreational shooting with it.

But MOA or better is easily possible, but I wouldn't load it on my xl650. I use a single stage for that gun, but I do throw the charge as +/- .2 gr isn't worth hand weighing.


I also tried RL 25, H1000, RL33 and US869. Retumbo gave most consistent velocity, filled the case well, and my 1st batch of Lapua brass lasted 9 reloads and that was BEFORE I began annealing.

Also I fl size my brass, trim every other load, and seating depth with the smk is very forgiving in my gun.
 
Last edited:
Watching with interesting as my brother just picked up a .338LM and I'll get him into reloading before long.

We took it out at the 400 yard range and one group of 5 measured .84 MOA with 4 of the 5 clustered into .33 MOA using factory Hornady 285gr AMAX.
 
So after extensive researching, I’ve decided that H1000 is a very good powder and the choice of many experienced 338LM shooters.

I also found a deal on SMK 300 grain boolits and ordered 3000 of those.

Federal 215 primers.

Next step is to buy a 338 LM conversion kit for my D650, on which I’ll use to seat the primers and size the brass. I’ll buy a single stage to seat the bullet, and a digital powder thrower. I don’t trust the Dillon powder thrower. I wish I had bought the Powder thrower when it was on sale last Christmas.

And I’ve yet to buy 338 LM dies. Gonna research those, too.
 
You must log in or register to reply here.
Back
Top