338-378 Weatherby Questions

[Magnum_Willys]

Son got a chance to shoot my reloads this morning.  5 shots in a 2.5" group at 500.   
300 gr. SMK, New Unprepped brass, 215m primer, 112.4 gr RL33.  3.795 oal
Just loaded brass right outa the box.  Doesn't get much easier than that.
2837-2852 fps.    Ave 2845.   

[bearpaw]

Son got a chance to shoot my reloads this morning.  5 shots in a 2.5" group at 500.   
300 gr. SMK, New Unprepped brass, 215m primer, 112.4 gr RL33.  3.795 oal
Just loaded brass right outa the box.  Doesn't get much easier than that.
2837-2852 fps.    Ave 2845.

That sounds great, how do you feel this bullet will do as a hunting bullet?

[Magnum_Willys]

I chose it as best available 1000 yard elk bullet based on reviews from unbiased guys who see dozens to hundreds of elk shot annually and who shoot it themselves.  Yorks tests on here confirmed its a much better choice than bergers.  The only caveat is at less than 300 yards like other premium bullets it supposedly could perform erratically if shooting 3000 fps.   If I was worried about it I would shoot a factory 250 nosler out to 300 and jack it out and chamber the 300 smk for longer shots but I plan on using it at all ranges - hopefully we find out this Friday !

[bearpaw]

I chose it as best available 1000 yard elk bullet based on reviews from unbiased guys who see dozens to hundreds of elk shot annually and who shoot it themselves.  Yorks tests on here confirmed its a much better choice than bergers.  The only caveat is at less than 300 yards like other premium bullets it supposedly could perform erratically if shooting 3000 fps.   If I was worried about it I would shoot a factory 250 nosler out to 300 and jack it out and chamber the 300 smk for longer shots but I plan on using it at all ranges - hopefully we find out this Friday !

That makes sense, I've got some other 338 bullets I can use at closer ranges... 

I'm trying to find where to buy those redding dies you said you use? Cabelas don't carry them.

[Magnum_Willys]

https://www.midwayusa.com/338-378-weatherby-magnum/br?cid=8211

I use the Lee Precision neck Die and the Redding  full length sizer die every 4 or 5 reloads as needed.  But for hunting I would just load factory new brass, then neck size - one box of brass should give you 60-80 shots at least till full size needed.   Lee precision neck and seating dies give least runout and are $160.

http://leeprecision.com/custom-collet-necksizing-large-series-die-set.html

I havent found a full length die that I like yet. Most shrink neck way down then expand it back up but not enough.  now that loads dialed in plan on just new brass and neck size till wont chamber. 

[bearpaw]

https://www.midwayusa.com/338-378-weatherby-magnum/br?cid=8211

I use the Lee Precision neck Die and the Redding  full length sizer die every 4 or 5 reloads as needed.  But for hunting I would just load factory new brass, then neck size - one box of brass should give you 60-80 shots at least till full size needed.   Lee precision neck and seating dies give least runout and are $160.

http://leeprecision.com/custom-collet-necksizing-large-series-die-set.html

I havent found a full length die that I like yet. Most shrink neck way down then expand it back up but not enough.  now that loads dialed in plan on just new brass and neck size till wont chamber.

Thanks for the info, I've two boxes of new brass screaming "load me"! 

So you think I should get the Lee for seating bullets? If I understood correctly they want two fired brass and the bullet I want to load to custom make the die?

Are you putting any crimp on your loads?

[Magnum_Willys]

I think the Hornady is good for seating, I use the redding with a micrometer top I have from another die on it which is nice.  The Lee works fine too.

I think Lee is the best for just neck sizing (only because you can't get a Redding bushing Die for this caliber)

But Just a Hornady neck and seating die for $80 should get some pretty good loads for you. 

If I was real particular ( I am) I would fire off a factory round (weatherby/norma brass) to get brass matching my chamber and send that with a 300 smk bullet to lee and have them make me a die set.  I know that will get you less than .001 runout typically if that matters. 

[Ziptie]

Great info!  I picked up a 338/378 acumark with hopes of using it as a 500 to 1000yds hunting rifle (I practice and have killed game at over 500 with my current set up).  I picked it up in a shop with a really really bad glass job, tossed the stock.  I fitted it with a new target style stock and gave it a proper glass/ free float.  I was planning on using 250gr pills but might jump up to 300 after this read.  Thanks again for posting there is not that much out there about this caliber. 

-Zip

[Magnum_Willys]

Great info!  I picked up a 338/378 acumark with hopes of using it as a 500 to 1000yds hunting rifle (I practice and have killed game at over 500 with my current set up).  I picked it up in a shop with a really really bad glass job, tossed the stock.  I fitted it with a new target style stock and gave it a proper glass/ free float.  I was planning on using 250gr pills but might jump up to 300 after this read.  Thanks again for posting there is not that much out there about this caliber. 

-Zip

pickup an inexpensive scope level to mount on the scope.  makes a difference over 500 yards.  With a good bed job and trigger its just about finding a good load. 

[Ziptie]

Not to hi jack but I just got mine out to the range for the first time (picked it up as a barreled action in need of attention).  I glassed it into a new stock and tossed a 6-18x lue on it.  Factory 250gr partitions are at 1" at 100yds.  I am happy for its first time out, I have ordered dies and 300gr SMK, will pick up some Re 33 and start loading for it.  I still need to tune the trigger (scary light) it is hard to use. I think a clean trigger break will shave 1/4 to 3/8" off my groups with the factory 250's.  Thanks for all the great info!   

[Magnum_Willys]

Did some shooting yesterday 8mph wind. Son brought his 338-378 with my custom 300 smk loads.   Cold bore, hadnt been fired since september.  First shot 1” low, 4” to the right rang the 10” steel at 994 yards.   I couldnt out shoot him with my custom Lapua.

Btw - 215m mag primers in stock at basspro as of yday. 

[bearpaw]

We finally got a new scope mounted on my 338/378 this spring and i'm going to make time to get this beast shooting. I really had a hard time deciding between Night Force, Leupold, and Huskemaw, I don't care for the busy reticles in Night Force and I'm already putting a 4x24 VX6 Leupold on my 6.5x300, plus my son is a dealer for Huskemaw so I decided to go with the Huskemaw 5x30. He has the 5x25 on his 30/378 and it does a great job for his intended purpose, so I'm going to try the 5x30 on this gun. If I decide it''s not what I want on this gun I can always get another scope for this gun and do some swapping around with another gun.

After considerable reading I just ordered one of those digital headspace gauges at http://www.larrywillis.com/, I'm anxious to see how it works, I'll try to remember to post again after I've used it. I'm hoping to keep the 338/378 brass as consistent as possible and I'll check some of the brass in other calibers I've been shooting for years.

I'm also ordering my 338/378 dies today so I can work up a load for this gun. I'm going to work up to the load posted by Magnum_Willys and see how that works in my gun. I have the same gun so I'm hoping for a similar load. I have the 300 gr SMK's, cases, and primers, I just need powder which should be available locally.

[Matth]

Any news on this yet, i just picked one up?

[bearpaw]

I think I have all my reloading stuff now, just haven't had time to do any reloads yet. I went with the hornady FL Die and Seater, and got their neck die and mircrometer for the seater die. I also got a concentricity tool and a headspace gauge. I've never needed these last two tools but figured they might benefit precision loading for this caliber and what I hope to do with it. Honestly I don't know if they are needed or not, but after doing some reading I decided I wanted to check that stuff too.

[Magnum_Willys]

Update:  My son used the 300 Gr SMK reloads this week in Idaho to down a nice bull at long range with his 338-378.  Rifle is bedded ( important!)  Best loads were factory new brass, 112.4 gr RL33.  He can hit 10" paper plate sized target at 1000 yards with this setup and did 3 times on this elk.