Re-barreling .308 to something big?

marksman1941

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May 20, 2013
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I have a 20" rem 700 sps tactical in .308 that has been a fantastically accurate rifle for me. At well over 3k rounds, accuracy is starting to go. Not bad, but 1/2 moa has opened up to around 1 moa which makes 1000+ a lot less fun.

I'm toying with the idea of making the .308 a stubby close range thumper and buying a Bergara 6.5cm for my long range toy.

What is the most ridiculous, yet feasible thing to turn my .308 in to? Here's my list of desires for the build that I'd like to match a caliber to
* Chop to 16" and thread for suppressor or brake. I may also form 1 a permanent suppressor depending.
* keep standard bolt and magazine length, or keep modifications to a minimum.
* create ridiculous energy inside of 150 yards. Ignore long range ballistics. Ignore recoil energy. Basically, the caliber you'd carry to walk into a briar patch looking for a wounded bear.
* something I can hand load for. I don't mind making ammo, even expensive ammo, as long as there are some components to be found for it.

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!
 
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338 Federal- short and suppressed?

My vote as well. I spun up an M14 barrel in 338 Federal for a shooting buddy in Slidell. It is his hog busting rig.

Fireforming. Before he went back to LA, we fireformed some brass.... rattled 30 cal bullets through 338 bore... easy peasy.
 
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I had initially looked at 338 federal (and 358 win is the same, just with a 35 cal bullet) but energy wise it still wasn't much of a step up above 308 in that configuration. Based on some googling and energy calculations, a 16" 308 shooting 165's should have about 2200ftlbs of energy. A 338F with 210's should have 2480ftlbs, and a 358win with 225's is about 2460ftlbs. I know energy isn't the be all end all, but it's certainly a part of the equation.

I guess there's not a huge difference between the 338 fed and the cartridges I listed though, when looking at published velocities. 450BM with a 250 gets me to about 2680ftlbs, but the others fall behind it with the exception of the 45 raptor.

Looks like the raptor sends a 300gr bullet at 2250fps for 3370ftlbs of energy. It would have the ballistic coefficient of a windsock but I'm okay with that.

I have a lot of rifles that work perfectly well for killing critters as needed. This one I was looking for the Thors Hammer effect on a critter, and also something a bit cool and out of the ordinary.
 
I have a Ruger #1 in 338 Federal.
I've been thinking of getting a prefit done for a bolt rifle! My only problem is my suppressors are 30's.
Another waiting time 😞
This is a problem for me too. My cans are all 30 and lower. Depending on what I make here I'll probably get a hybrid 36 or hybrid 46 so I can run everything, if I don't go the permanent route
 
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