338-378 info?/experiences

[TEAMSENDIT]

I was wondering what experiences people have with the 338-378 cartridge. seems like it would be a great long range cartridge. brass is spendy but so is the 338 lapua so what gives, i never hear of anybody using it. Seems like a good compromise between lapua and snipetac.

don't get me wrong i didn't consider it either since i am building a 338 edge right now. but looking back it seems like a viable cartridge in single shot form. shit most reports show you can push a 300gr bullet to 3000+fps.

any pics/opinions/experiences are obviously welcome.

 

[QRE23]

Re: 338-378 info?/experiences

The 338-378 has a pretty good sized powder capacity advantage over the standard 338 Lapua which gives it a good 150+fps advantage. More often, you hear the 338-378 compared to the 338 Lapua Improved. These two are very close to the same FPS. Brass is quite a bit more expensive for the 338-378 and is of less quality. With a 30in. tube you can get 3000fps with a 300gr. but brass life will be considerably shortened and more often than not your accuracy loads are going to be under that 3000fps mark.

I believe WBY is the only company that offers a 338-378. IMHO, based on the 5 different factory WBY's I've owned, it's the luck of the draw with WBY rifles as to getting one that shoots well versus one that doesn't. I currently have a Accumark 338-378 that is about a 1 moa gun. Not bad but certainly nothing to write home about. I don't get even close to some of the FPS #'s I hear some talk about. If you are looking for the biggest baddest factory 338 boomer then the 338-378 is what you are looking for.

If you are looking at building a custom and you want a 338 that will get you 3000fps with a 300gr and you don't want to break the bank a 338 Lapua Improved is a better choice.

 

[lynxpilot]

Re: 338-378 info?/experiences

100% with samson. I, however, opted to re-barrel. Bought a 30" heavy palma contour from Bartlein and it's off to the smithy right now for chamber and headspace. Will be chambered 'match' which will not have the typical Roy freebore. I'll probably lose a few fps from loss of freebore, most of which will be gained back by going from 26" to 30" barrel. Should add some accuracy both by the top-notch barrel and reduced freebore. I'll know in about a week.

Out of the box, it's about 1 MOA. I didn't apply science, but I'm still convinced that the whippy fluted barrel that comes stock with the Accumark doesn't help accuracy at all.

 

[billt]

Re: 338-378 info?/experiences

I've been shooting this .338-378 Weatherby Accumark for around 10 years now, and I'm really surprised this caliber hasn't become more popular than the Lapua round, especially in this country. I think if Weatherby put this caliber in a heavier, tactical type rifle with a 30" heavy, fluted, Stainless barrel, they'd sell the hell out of it. As was mentioned it bests the Lapua .338 in both velocity as well as energy. Mine continually goes under 1" without any fuss. The gun is a beautiful long range performer. Bill T.

 

[AQC440]

Re: 338-378 info?/experiences

<div class="ubbcode-block"><div class="ubbcode-header">Originally Posted By: Bill T</div><div class="ubbcode-body">

I've been shooting this .338-378 Weatherby Accumark for around 10 years now, and I'm really surprised this caliber hasn't become more popular than the Lapua round, especially in this country. I think if Weatherby put this caliber in a heavier, tactical type rifle with a 30" heavy, fluted, Stainless barrel, they'd sell the hell out of it. As was mentioned it bests the Lapua .338 in both velocity as well as energy. Mine continually goes under 1" without any fuss. The gun is a beautiful long range performer. Bill T. </div></div>

I have often wondered about this myself. I think people are sometimes turned off by Weatherby's having so much "freebore", but I don't see how that could be a bad thing when shooting bullets as long as your little finger...