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 .338 Rem Ultra Mag vs. .338 Lapua
pazzo  [Member]
4/24/2009 2:01:30 PM
Which would you prefer and why?
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300ultramag  [Team Member]
4/24/2009 2:13:09 PM
the 338RUM will cost slightly less to reload, and you CAN get a little more velocity out of it, but it wont be much. its cons though, no loaded "match grade" ammo is available, and barrel life is less than that of the 338LM. the 338LM has a longer barrel life, and factory match ammo if you need it, so thats the selling point for me. the barrel life is the biggest factor.
GONIF  [Member]
4/24/2009 2:28:42 PM
+1 the LM will last longer . there is another super .338 the .338-378 Weatherby mag . I have an Accumark in .338-378 that I use for long range elk hunting . I'm a big fan of the .338 LM and will (if I ever get the money ) get a Sako TRG 42 some day .
AshesToAshes  [Team Member]
4/24/2009 2:54:30 PM
It depends on what you want to do. If you want a rifle for hunting dangerous game, go with the .338 RUM. If you want a target / sniping rifle (or just bragging rights), go with the .338 LM.

I am the proud owner of a TRG-42 in .338 LM and wouldn't trade it for any other rifle on the planet. It's the choice military sniper rifle for many countries, and Beretta is now importing the 1x10" barrels so you can chuck the 300gr ammo downrange. The .338 LM round is fantastic when in the hands of an experienced shooter. Perfect for long range precision, and with the right powder, you can get up over 3000 fps.

The .338 RUM is a good round too. Slightly less energy than a .338 LM, from what I can tell, but I'm sure you can hand load something close. I don't know what twist rates the .338 RUM comes in, but you should check first to make sure you can get one with a twist that can throw a 300gr bullet; most .338 RUM rounds I see are 200 - 250gr.

If you take good care of your brass, it will last you a long time - so they will end up costing you about the same to reload.

Both rounds are a pain in the ass for precision shooting. You'll likely want a muzzle brake. If you shoot without one, the rifle will jump out of your hands unless you hold it tight... and if you hold it tight, your accuracy will no doubt suffer.

One other thing to note: both are small bore magnums (or at least medium bore), and likely to wear fast. I've read that my TRG has a life expectancy of 1000-3000 rounds.
300ultramag  [Team Member]
4/24/2009 3:12:55 PM
Originally Posted By AshesToAshes:
It depends on what you want to do. If you want a rifle for hunting dangerous game, go with the .338 RUM. If you want a target / sniping rifle (or just bragging rights), go with the .338 LM.

I am the proud owner of a TRG-42 in .338 LM and wouldn't trade it for any other rifle on the planet. It's the choice military sniper rifle for many countries, and Beretta is now importing the 1x10" barrels so you can chuck the 300gr ammo downrange. The .338 LM round is fantastic when in the hands of an experienced shooter. Perfect for long range precision, and with the right powder, you can get up over 3000 fps.

The .338 RUM is a good round too. Slightly less energy than a .338 LM, from what I can tell, but I'm sure you can hand load something close. I don't know what twist rates the .338 RUM comes in, but you should check first to make sure you can get one with a twist that can throw a 300gr bullet; most .338 RUM rounds I see are 200 - 250gr.

If you take good care of your brass, it will last you a long time - so they will end up costing you about the same to reload.

Both rounds are a pain in the ass for precision shooting. You'll likely want a muzzle brake. If you shoot without one, the rifle will jump out of your hands unless you hold it tight... and if you hold it tight, your accuracy will no doubt suffer.

One other thing to note: both are small bore magnums (or at least medium bore), and likely to wear fast. I've read that my TRG has a life expectancy of 1000-3000 rounds.


my TRG without 1-10 twist shoots the 300SMK's i load for it just fine, but from my understanding not all do.

the 338RUM with handloads will be more energy than the 338LM because you can get a little bit mroe velocity with the 338RUM. your probably comparing a 300gr SMK 338LM load to a 200-250GR 300RUm hunting load, of course the hotter and heavier 300SMK lapua load is going to have more energy, but since you can drive a 300SMK slightly faster from a 338RUM (only about 50FPS) it will have slightly more energy aswell.

a brake is certainly a must, and unless the OP is using it for its true potential (1200-2000 yards) then its just overkill period and would be much better suited with a 308, 243, 260, 6.5X55, 7mm-08, or any of the other cartridges that will get to 1200 yards just fine, have less recoil, and cost a whole lot less.

the reason the 338LM has a longer barrel life is because it doesnt have anywhere near as sharp of a neck angle as the 338RUM, that will burn a throat out in short order.
AshesToAshes  [Team Member]
4/24/2009 3:16:57 PM
Hmm, all of the factory .338 RUM (250gr) I see is only 2860fps - 2900fps. You must be able to hand load it much higher. Most of the factory .338 LM I see is 2975fps. What are the pressure standards for each caliber?

Do they have .338 RUMs with twists that can handle 300gr?
bfarrin1  [Team Member]
4/24/2009 3:31:21 PM
At +/- 2500 rounds, the throat on my 1st 338 RUM Sendero had moved +/- .080".

It was still shooting less than an inch at 100 yards.

Due to the length of the factory throat and the subsequent wear, I was unable to maintain my desired jump to the lands and accuracy began to suffer.

The second was taken off somewhere around 200 rounds without any measurable wear to the throat. Although at that point I'd settled on RL-25, which may have had something to do with it.



Something to consider - The 338-300 RUM(338 Edge), with an appropriate throat length along with the higher quality Nosler 300 RUM brass will significantly narrow the gap (if there was one at all) between the RUM and the Lapua case. Brass is formed in one pass through the sizing die, dies are off the shelf items at Redding.



Recoil is subjective. I'd not consider a muzzle brake unless it was absolutely necessary.
AshesToAshes  [Team Member]
4/24/2009 3:32:26 PM
Perhaps OP could state what their intended use is, that'd help better answer this question.
pazzo  [Member]
4/24/2009 3:58:23 PM
Originally Posted By AshesToAshes:
Perhaps OP could state what their intended use is, that'd help better answer this question.


Thanks for all the answers guys.

Intended use would be as a 1000 yd gun for target shooting. And of course to add another cool bolt gun to the collection.

AshesToAshes  [Team Member]
4/24/2009 5:12:48 PM
Originally Posted By pazzo:
Originally Posted By AshesToAshes:
Perhaps OP could state what their intended use is, that'd help better answer this question.


Thanks for all the answers guys.

Intended use would be as a 1000 yd gun for target shooting. And of course to add another cool bolt gun to the collection.



Since you used the word 'cool', I assume you'd love to have bragging rights. These come with the .338 Lapua. It doesn't matter if you're a complete n00b to guns, when you say ".338 Lapua", people's eyes begin to sparkle at the gun club and envy ensues.

On the other hand, once you mention you're using factory ammo, everyone will dismiss you as a n00b again and the sparkle wears off... so if you want bragging rights you'd better reload too.

All else aside, if you are doing long range work, all I can say is make sure whichever cal you get, that it's got a good length target barrel, a 2lb or less match trigger, and a muzzle brake.

ChrisGarrett  [Member]
4/24/2009 7:14:00 PM
Originally Posted By pazzo:
Which would you prefer and why?


I don't have a preference, but I went with the 338LM and a Sako TRG-42. For the money I can't complain. You'll probalby pay less for 338RUM brass, but the Lapua brand 338 is pretty stout and I'm on my tenth cycle. I can't say if you'll get this out of RP brass, but over the long haul, it's probably a wash.

The Finnish Army snipers did extensive tests and for their requirements they figure that the CrMo barrels are good to about 4000 rounds. I've read of people yanking TRG barrels at 1500 rounds and ditching them, but 4000 is the rule, it seems in military trials and for military needs. I can't speak to other barrel makers and their lifespan. Obviously, benchrest shooters might beg to differ. I load to the distance that I'm going to shoot and that isn't any farther than 1k, so if you don't need to shoot 1600m, don't load hot and save your throat.

The 338LM will hold an est. 111.8 grains of H2O and the 338RUM will do about 104.6 grains, so you should be able to pack in a bit more powder for the 338LM vs. the 338RUM.

Chris

300ultramag  [Team Member]
4/24/2009 7:32:14 PM
for 1000 yards 338LM is overkill, there are much better choices.
AshesToAshes  [Team Member]
4/24/2009 8:57:57 PM
Originally Posted By 300ultramag:
for 1000 yards 338LM is overkill, there are much better choices.


depends on how heavily armored the paper target is
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