Author Topic: 338 win mag vs 338 ultra mag  (Read 1947 times)

Deputy sheriff

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338 win mag vs 338 ultra mag
« on: January 21, 2015, 09:26:45 AM »
I was looking at load data for the 338 win mag and noticed that the 338 ultra mag uses 91 grs as opposed to 78 grs of RL19. This is for the 225 gr bullet but only results in a gain of 84 fps. Is this not a waste of powder for fps gain, overbore?
If you are too busy to hunt , you are too busy.

JIMMY 808

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Re: 338 win mag vs 338 ultra mag
« Reply #1 on: January 21, 2015, 11:23:35 AM »
RL 19 really wouldn’t be my first choice for the 338 RUM
 There are a few ways to squeak out the last available amount of FPS from a cartridge and case design plays a role as well.  In my experience the rifle itself will dictate the final loads and there is no reason you can’t adjust that either to match a cartridge.     

338 win mag without messing around too much is tough to beat.         

BruceW

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Re: 338 win mag vs 338 ultra mag
« Reply #2 on: January 21, 2015, 12:26:59 PM »
My 338 likes 71gr IMR 4831 with a 225gr lead. (actually just got back from the farm, 3 shot kneeling group could be covered with a toonie.) I think if you want a quicker bullet the next step up is a 338-378, but good luck finding a used one (I looked for years), and new one's are quite dear.

Don't know anything about the ultramag.

Deputy sheriff

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Re: 338 win mag vs 338 ultra mag
« Reply #3 on: January 22, 2015, 10:58:36 AM »
Thanks guys, I always appreciate the feedback from knowledgeable reloaders and shooters.
If you are too busy to hunt , you are too busy.

BruceW

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Re: 338 win mag vs 338 ultra mag
« Reply #4 on: January 22, 2015, 05:35:25 PM »
knowledgeable reloaders and shooters.

Well I don't know if I'd go that far, I just like to shoot and reload, and shoot some more.  The more I learn the more I realize just how much I don't know, so we've just gotta help each other where we can.  :)

catnthehat

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Re: 338 win mag vs 338 ultra mag
« Reply #5 on: January 23, 2015, 07:24:05 AM »
Typically when you get those monster sized cases like the ultra mags, Lapuas, and the Weatherbys, they really gain their full potential with the heavier, longer bullets, but within 500 yards you don't see any difference in killing power between them and a 338 Win mag using a lighter weight bullet for the 338.
Before range finders I think there may have been an argument for a flatter trajectory, but these days a flatter shooting cartridge is not as important.
That being said, lots of guys shoot those big 338's because they are fun , but without a brake on a rifle no gun ina hunting weight sporter is much fun IMO!! :P
Cat
Well, now, that didn't work so good......