Re-barreling .308 to something big?

[marksman1941]

Suppressed with 325 grain Makers is absolutely Hollywood quiet. I wanted to do 350's or 400's but Paul said my 12 twist wouldn't stabilize em. The 325's hit like a freight train tho!

I know even 220's subsonic in my blackout are movie quiet and surprisingly solid impacts, although nowhere near supersonic impact energy. Subs are just dang fun to play with.

 

[marksman1941]

Bore helps a lot. Having played with wsm and rum variations its rather substantial the gain for equal weigh as bore increases. My 375 ruger gets the 270class bullets right near 2900, and single digits e.s in the mid 2800s. I do wonder how the tough jacket Bullet options will do with a 2400 launch speed.

How the bullet performance for those lower bullet speeds?

In theory, a .375 Sierra gameking is supposed to expand down to 1800fps. Which gives you a solid 300 yards of bullet performance I believe.

 

[Ark. Trapper]

In theory, a .375 Sierra gameking is supposed to expand down to 1800fps. Which gives you a solid 300 yards of bullet performance I believe.

Exactly!

 

[budlight]

So what are my options? I've been looking at the 458x2" American, 450 BM, 458 socom, 45 raptor, or 50 beowulf, items in that range, but I'm new to big bores and all the options that I can use a .473 bolt head for (I don't actually know if all the calibers listed above use the .473 bolt head either). My initial thought had been to bore out to a 358win, but with a 16" barrel it actually makes less energy than a standard 308 out of a 20" barrel so I didn't see much gain there.

Any input is appreciated!

I have a .458 WM and a Barnes American .458. Both require a bigger bolt face and they are really fun rifles.

Parent case	.375 H&H Magnum
Case type	Belted, straight-tapered
Bullet diameter	.458 in (11.63 mm)[1]
Neck diameter	.481 in (12.2 mm)
Base diameter	.513 in (13.0 mm)
Rim diameter	.532 in (13.5 mm)

 

[marksman1941]

I have a .458 WM and a Barnes American .458. Both require a bigger bolt face and they are really fun rifles.

Parent case	.375 H&H Magnum
Case type	Belted, straight-tapered
Bullet diameter	.458 in (11.63 mm)[1]
Neck diameter	.481 in (12.2 mm)
Base diameter	.513 in (13.0 mm)
Rim diameter	.532 in (13.5 mm)

I have a 1917 eddystone in .270 that will never be used as a .270. It might be a good candidate for a rebuild into something big like a .458

 

[Fatcatbuster]

Man that is impressive. I wonder what barrel length they tested that velocity at?

I doubt it it was any shorter than 20"..

 

[del2les]

Meet the 375 Raptor: a Heavy-Hitting, Short Action Cartridge - The Truth About Guns

&#9664Previous Post Next Post▶ Arne Brennan, creator of 6.5 Grendel and other cartridges, designed 375 Raptor in a quest to do for 308 Winchester what 300 Blackout did for .223 Remington. Namely, neck it up to run larger, heavier bullets that deliver both supersonic and subsonic performance in a...

www.thetruthaboutguns.com

"For example, in particular from barrels between 10 and 18 inches in length, 375 Raptor will fire a 260 grain bullet at the same velocity that 308 Win will fire a 180 grain bullet despite using the same amount of gunpowder (case capacity is actually slightly lower) and the same maximum pressure."

"A fantastic, all-around hunting load capable of confidently taking any animal in North America is the 270 grain Speer Soft Point Boat Tail bullet, which is very affordable, shockingly accurate, and absolutely devastating on big animals. When loaded in 375 Raptor, velocity ranges from 2,100 FPS to 2,400 FPS depending on barrel length (10-inch to 20-inch)."

 

[marksman1941]

Meet the 375 Raptor: a Heavy-Hitting, Short Action Cartridge - The Truth About Guns

&#9664Previous Post Next Post▶ Arne Brennan, creator of 6.5 Grendel and other cartridges, designed 375 Raptor in a quest to do for 308 Winchester what 300 Blackout did for .223 Remington. Namely, neck it up to run larger, heavier bullets that deliver both supersonic and subsonic performance in a...

www.thetruthaboutguns.com

"For example, in particular from barrels between 10 and 18 inches in length, 375 Raptor will fire a 260 grain bullet at the same velocity that 308 Win will fire a 180 grain bullet despite using the same amount of gunpowder (case capacity is actually slightly lower) and the same maximum pressure."

"A fantastic, all-around hunting load capable of confidently taking any animal in North America is the 270 grain Speer Soft Point Boat Tail bullet, which is very affordable, shockingly accurate, and absolutely devastating on big animals. When loaded in 375 Raptor, velocity ranges from 2,100 FPS to 2,400 FPS depending on barrel length (10-inch to 20-inch)."

That pretty well sums it up doesn't it

 

[HunterMann]

If you do the mag route the raptor gets positive feedback, basically a bolt action 4570 with 452 bullets.

My conundrum is balancing power and recoil. I could easily swap a bolt face and make a 375wsm.... but know in a 13lop manners, with a light contur 16 inch barrel on a model 7 or kimber it kills both ways. 308 powder column seems like as big as I can go.

The 375 raptor looks good but, the 452 bullet selection is vast and cheap... the 375 not. Most modern 375 bullets like 375 have launch speeds as well.

I've come full circle and just stuck with a slightly fast twist 308...

.375 Speer Hot Core 235 grain bullets can perform well at velocity you can get out of a 308 case.

 

[ATH]

I was in this situation....16.25" 458 SOCOM with a Griffin Bushwacker suppressor. Only mod was a bit of touch up on the Wyatt detachable mag and I did install a M16 extractor as the factory one liked to drop the round before the ejector could fling it.

 

[marksman1941]

I was in this situation....16.25" 458 SOCOM with a Griffin Bushwacker suppressor. Only mod was a bit of touch up on the Wyatt detachable mag and I did install a M16 extractor as the factory one liked to drop the round before the ejector could fling it.

How did you settle on 458 socom?

 

[ATH]

How did you settle on 458 socom?

My primary intent was to shoot subsonics large enough I felt comfortable hunting deer with them, and 300BLK I was not comfortable with. I already had SOCOM gear as I have an AR15 chambered in the round. I don't plan to shoot supers through it, but I could, and if I did, it would still be a great short range thumper with higher energy. With 325s it keeps up with 45-70. For a sub-150yd gun the big bores are hard to beat. As a bonus it fits a 308 bolt face and it didn't take much to get it to feed from 308 mags.

The short case length was the most difficult part. It angles steeply off the ejector so that made it a bit finicky. With the factory ejector it actually jammed on the bolt face due to the rim to fat case body dimension. The M16 extractor fixed all this.

 

[comfisherman]

A lot more bullet options across a broader weight spectrum designed around that m.v. as well. With the last decade and a half of Topsy turvey that's definitely a selling point.

 

[pavementends]

I am surprised that no one suggested the 9.3BM Requires a bolt face alteration but there is a good deal of information out there. Pretty well duplicates the 9.3x62 in a short action. Great bullets and a world of experience in Africa in the x62 form.