I have a friend who is a 30-378 nut and I am a fan of the 7mm bullets (284). He wants to make or buy a 7mm-378. I think there are already cartridges out there to fit the bill, but he says I need to think outside the box.

So is there already a 7mm-378? (I am sure someone has built one) Anyone have an opinion on the matter? Just an interesting topic to think about.

I think you would have trouble burning that much powder in a 7mm. The 7.62 warbird is still about 10-13 grs smaller. Plan on swapping barrel often.

quote:

he says I need to think outside the box.

and he needs to think inside the brain.....

okay.. wait a second...

is his goal to have a smoothbore .284 barrel? there's easier ways than burning 1/2 a cup of powder at a time, and not beating 7stw velocities.

and if you want to burn MORE powder, for 50fps gain, go with a 7 RUM...

7x378 ...barrel life MIGHT be longer than sighting in the scope..

might ..

the only thing outside the box on that this the rifling being blasted downrange
jeffe

Just a couple rough numbers ran through Loadtech before coffee.

All with 26" barrels and a 150 bullet max velocities and powder at 64,000.
7STW 3490 79.8grs
7Ulta 3506 82.6grs
7.21 firebird 3490 90.9 grs
7-378 3455 112grs

Hey I would love to burn a lot more powder for a loss. If I increase the barrel to 30" I can get the 7.21 and 7-338 to around 3575. But giving the 7STW the same 30" gives 3570 with 10-25 grs less powder.

I found this very interesting.
http://www.reloadingroom.com/page19.html
Here I thought 25 years ago I had been smart to determine 77-79 for a 7mm. This would have saved me work. LOL

Ahhhhhhhh, is this what it feels like to be right? I knew you guys would have more info than me on this, but it sure seemed like he had a wacky idea. Thanks for the input. I'll have my buddy read this post and then just tell him to spend the $1,000s on a good tag to go hunt.

Could this be the start of a Super Super Ultra Super Magnum plus group of Cartridges-

.22-378
6mm-378
270-378 etc- you can add your own here

Before you start however let me buy shares in pac-nor and Hodgdons.

Or how about trying out one of those "unfashionable" antiquities the 7 mm Rem or STW!!