Home Forums Hunting & Shooting Gunsmithing 270 win. Montana to 270 Wby. Montana

OK, I need a little help from all the 24 Hour experts.

I would like to rechamber a 270 Win. Montana to the 270 Weatherby cartridge. I know the bolt face diameter will need to be opened up with the rechamber. My questions are, is the magazine length long enough and am I missing anything else in the conversion that will not make it work? Bolt face diameter large enough? Trying to avoid a rebarrel on a magnum length action if possible.

Thanks

Well besides modifying the bolt there is the issue of modifying the feed rails, but first consider that what you'll end up with is a rifle with a shorter than optimum barrel for the round and a less than optimized barrel twist rate to take advantage of the extra powder space.

A 270 Win is already a good performing round and converting to 270 WBY I doubt there will be any noticeable difference in the field that would justify all the effort and the nuisance of having to deal with Weatherby brass that is soft and expensive.

Montanas are available off the shelf in 270 WSM. While I am not a big fan of the round, it's a 270+p and some friends of mine really like it and have long barrel, fast twist rifles that are long range hammers with heavy bullets.

There are some plain old 270 Win and AI rifles in the bunch too. They are very accomplished long range shooters because of their experience and there is not a lot of difference in their success rate between the rounds that I can see.

If you are not doing the work yourself, it seems like a way to spend a bunch of money just to take a step sideways and you could have just spent the money on a 270 WSM Montana if that's what you want.

It's likely not what you want to hear, but the 270 Win is pretty good as it is.

I agree.

It's been damn good since 1925. Why mess up a good thing and throw money out the window???

I believe that action is designed to the minimum diameter that works with .473" head cartridges so a belted mag simply can't fit.

If this is a Kimber Montana, There is not enough steel in the 84 to take a belted magnum. The action is designed around the 30-06 family. You would have to step up to the 8400 family.

Headache

270 gibs biggest gain for least effort.

Ed

Take the simple and probably the most economical route. Sell your 270 Win. Montana and buy a new rifle in .270 WSM. You'll get performance similar to the Weatherby round and be ahead financially.

I find the 270wby to be superb on game and offers similar performance to the 270wsm. The 270 win is a great caliber, however I prefer to step it up a notch and hunt with the 270wby pretty fequently.

I can't speak to the suitability of the Kimber Montana action for this conversion. But I've done it on Remington 700, Ruger 77, and Sako AV actions. You shouldn't have to screw around with the feed rails. A .270 Win magazine box is long enough for the short Weatherby mags.

Not recommended if the barrel is less than 24".

The increase in performance is real and noticeable in the field. Keep in mind that the resale value on the rifle will almost certainly drop somewhat.

Are we dealing with a Montana Rifleman gun?...or a Kimber Montana?

The MRC could be converted. The Kimber 8400 in 270 could be converted,....a Kimber 84L?....no.

Kimber Montana rifle.
Thanks for all the replies.
I tend to agree with Mathman's statement about receiver design size for '06 sized brass. Was just thinking it would be a nice rifle in 270 Wby. if I could pull it off.
I agree, nothing wrong with the 270 Win., but have a couple already. May just try out a Montana in 270 wsm.


The MRC could be converted. The Kimber 8400 in 270 could be converted,....a Kimber 84L?....no.

rembo,
Why could a Kimber 8400 in 270 be converted to 270 Wby. and a Kimber 84L not be. Are they not the same actions?

8400 is magnum diameter.

The 8400 is a larger diameter action and bolt than the 84L. The 84L is a stretched 84M, only large enough for cases with a .473" head. The 8400 is large enough for magnum cases with a .532" head. Before the 84L was intro'd the 25-06, 270 and 30-06 were chambered in the 8400 action.

OK, thanks all for the information provided. I'll have to think this one over and see which route I'll go. Looks like I would have to buy a 8400 action rifle and rebarrel to 270 Wby.

If you are dead set on the Wby then go for it, but the 270 WSM is easily the equal, and the better in terms of efficiency, accuracy and overall utility.

My buddies that have befriended the 270 WSM see all the range and no difference on game waaayy out there to 1000yds when compared to their 300 Win rifles, and with half the recoil.

That's their experience but they have a lot of that and basically know what they are doing. If the Wby was better in any way their rifles would be so chambered...a chamber is just a hole in the barrel.

Both chambers will need a rebarrel to a faster twist that can make the best use of newer, high BC bullets for the caliber if the goal is longer range. If long range isn't the goal, then there is no point over the 270 Win.

Either way, I'm not really a 270 guy, so if I were going to rebarrel a Montana I would go 7WSM or a similar flavor.

Bullets make a difference...chambers not so much.