Resizing 30.378 weatherby down to 7mm or 8mm

[lancetkenyon]

Why not go to a 7mm-.338LM? You have the action size already.
Or a 7mm Allen Mag.

 

[OldElkHunter1961]

Three first blush thoughts:

1. Is the juice worth the squeeze?

2. Can the windmill be beaten in this joust?

3. Was a question asked that deserves an answer?

Carry-on.

 

[Taylorbok]

There's a couple ways to do what you are asking. as mentioned I would suggest a different cartridge.
You are going to need a chamber reamer or find someone who has one, you could get CH4D to make you a sizing die off of reamer print.

 

[cvixx]

Decades ago I had lots of .308 brass but needed .243, so I necked them down. From eco Erie de, get a inside neck reamer for whatever caliber you end up with and use it. I had a hand crank Forster, but probably have something more recent.

 

[JamesWilson5]

Where did you get your 8 mm brass from?

Had got it here and there bout 6 to 8 years ago stocked up on it it back when it got hard to get primers years ago

 

[timo308]

When you're drivin a top fuel dragster, you're not real concerned with fuel economy.

No, but you have to have enough top fuel dragster left when you get done completing your test runs to still take to the races.

 

[JamesWilson5]

Oh I got plenty of gas and can fuel up several times over

 

[JamesWilson5]

I just enjoy the sport of hunting and lots of shooting with my family been going on for years starting to get a lil good at to

 

[JamesWilson5]

To answer lance I have all the rums and ran out of powder compacity the lapua might but it would have to hold at least 10 grain more but instead of buying a lapua and thers is nothing wrong with them. Big fan of the lapua. I already have the rifles already chambered in the 30 and 338 378

 

[DUCKMAN11]

I'm out on the 7mm-378. If a 30-378 is a "Cadillac" then a 7mm-378 is something with the word NASA painted on the doors! Too much to go wrong. Meaning that.... in my experience..... cartridges that are overbore and extremely overbore tend to have very narrow accuracy nodes. I have a 25-06 that prints ragged 1 hole groups at 45° and opens up to 3/4moa at 90° with retumbo and 115vld's. Meanwhile one of my friends has a 6.5x47 that shoots one hole groups with powder charges that span 1.5gr of powder and 125fps. He can literally load sub moa rounds with a scoop, Meanwhile I'm counting kernels. There are not a lot of 8mm bullets out there but there are a few good ones. If it were me I'd be looking at 375" projectiles if you don't already have a 338x378wby. If you don't have a 338x378wby rifle then it would be my first choice.

As far as dies go to neck up or down.... just get a set of FL bushing dies from redding and an expander mandrel and get ready to neck turn.

 

[tribb]

I know lot of people knock on the 8mm but there is a 323 Jarrett that has very good velocity . The 338 rum with 180 accubond gets over 3500fps by book standard nosler reloading manual out of a 26 inch barrel. But the case is full of 7828ssc barely can seat the bullet. That's why I was thinking the 378 more volume plus longer barrel. Recoil doesn't bother me so not worrying about that . But with a possible 15 + grain of powder slower burning powder to watch for pressure. I could see an easy 3650+ fps with 180 bullets and a good posible of 3500+ with 200 grain bullet that would kill clean and smoke anything in north America at a long range or short with right bullets hammer bullets barnes nosler

You folks may be on the way to making the 8mm.the next extreme long range top dog. Keep working and keep us posted. Tribb

 

[adam32+P]

Search here and the ol internet for 7-378 Wby...it's been done countless times and isn't as great as it sounds. Brass is too soft and way too overbore.

 

[Harry Knutz]

I have a Sako M995 in 30-378, It knocks things down on both ends , Not my favorite rifle to shoot, But I do take it out once in a while, Scopes are hard to keep in place too!

 

[JamesWilson5]

Sako are good rifles