.338 Build on Rem 700

[Radosilver]

I am looking to rebarrel a Rem 700 standard long action into a .338 caliber magnum of some description simply because I think it will be fun to do a build and I don’t have anything .338 caliber at the moment. It will be a hunting rifle for primarily elk, moose, and deer. Something in the 8.5 - 9ish lb. range with a 21-22” barrel (the older I get the less I like long tubes). I’m not trying to make this into a super long range setup. I want to shoot bullets in the 225 to 265 grain range and have enough punch at 600-700 yards to kill if I’m proficient enough on my end. My questions for those more knowledgeable than me are:

1. Are my options limited to .338 Win due to the standard length Rem action or can I consider a .340 Weatherby or .338 RUM?

2. Will I need to do anything to the feed rails? A .300 Win case seems to fit fine in the mag box and feed even though the donor rifle is a .30-06 ADL.

3. If the answer to number 1 is that cartridges longer than the .338 Win are on the table should I go .338 Win, .340 Wby, or something else. I’m really leaning hard toward those two, and think I probably want to stick with the Win, but that extra Wby velocity is making me wonder.

Thanks!

 

[BAKPAKR]

If you are going from a 30-06 to a magnum cartridge, you will need a new bolt or have the existing bolt face machined out. Having had two rifles built with donor Remington 700 actions, I would recommend selling that rifle and buying a action spec’d the way you want it.

With your existing bolt, you could do a 338-06 or a 338 Weatherby RPM.

 

[Radosilver]

If you are going from a 30-06 to a magnum cartridge, you will need a new bolt or have the existing bolt face machined out. Having had two rifles built with donor Remington 700 actions, I would recommend selling that rifle and buying a action spec’d the way you want it.

With your existing bolt, you could do a 338-06 or a 338 Weatherby RPM.

Thanks. I know I’ll have to address the bolt. What issues did you run into that makes buying the new action a better route?

 

[BAKPAKR]

Thanks. I know I’ll have to address the bolt. What issues did you run into that makes buying the new action a better route?

I had a lot into my Remington 700 actions after accurizing, bolt fluting, new bolt knob, new extractor, and milling for extended Wyatt’s mag box. I didn’t get a side bolt release added. Costs for each of these things add up quickly. A custom action usually comes stock with all of these features, and many custom actions accept shouldered pre-fits.

 

[Slickhill]

All 700 long actions are the same length. A 30/06 mag is as long as a 375H&H mag as far as factory Remington parts go.

If you have a 30/06 now there’s a good chance the rails will need to be opened and the ramp massaged if you go to a big fat magnum like a RUM.

Easy button with your setup will be the 338/06. No feed issues, nothing required but a barrel. I’m sure you could run the numbers on some of the newer sleek tipped bullets and find something that will get you to the ranges you are looking for with less powder, noise, and recoil.

 

[MT762]

All 700 long actions are the same length. A 30/06 mag is as long as a 375H&H mag as far as factory Remington parts go.

If you have a 30/06 now there’s a good chance the rails will need to be opened and the ramp massaged if you go to a big fat magnum like a RUM.

Easy button with your setup will be the 338/06. No feed issues, nothing required but a barrel. I’m sure you could run the numbers on some of the newer sleek tipped bullets and find something that will get you to the ranges you are looking for with less powder, noise, and recoil.

^As mentioned above, you'll need a new bolt (or to have your existing bolt modified which will probably cost about the same. Plus, the inside width of the rails is different, though maybe that will be fine.

Yet another opinion:

338-06 is a ton of work and doesn't give the jazz to launch long slick 250g bullets which is sort of what you're after if you're trying to shoot 700 yards on game. Plus resizing brass, or trying to track down headstamped brass, zero factory ammo anywhere.

(you didn't ask this, but if you're looking to step up in killing power and use your existing, unmodified action, 35 Whelen is a great choice). I have messed with all three rounds that have been brought up here and the 35 Whelen is the one I still own. With 225grain bullets and a 22" barrel it's a 500 yard round at sea level. Wind drift is about the same as a 308 shooting 175 Gold Medal Match.)

But back to your goal: If your absolute desire is beating the wind at 600-700 with something larger than a 30 cal bullet, then a 338 Win mag running slick 250gr bullets is a great choice. I would definitely go with a 1:9 or 1:8 twist because bullets keep getting longer and if you're not going to run a faster twist...just buy a used Rem 700 in 338 win mag. Most people don't look shooting them so the barrels on those rifles are usually pretty fresh.

The only advantage to building your own instead of keeping an eye on gun broker is that is screwing on a fast twist (1:8) barrel that will let you get down and dirty with long slick bullets.

Back to your current action: quite possibly your existing feed rails will work. Load some 300 win mag dummies and feed them with a full box (from both sides of the feed rail, not just with one round) and make sure it runs.

Then you could find a magnum bolt on Ebay, buy a 1:8 twist barrel, and send to the gunsmith of your choice.

Or....LRI can def modify your 30-06 bolt face to a magnum diameter and put one of their slick new extractors in. And screw a fast-twist barrel on for you.

 

[bhovda]

A 33 nosler setup with a proper reamer could be fun. But you'd have to research what the coal to mag length would be