Resizeing 30-06 brass to 270

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kevinm

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has anyone ever resized the 30-06 to 270 they look to be almost the same by the books. thanks
 
I do it all the time, but be aware of one important difference.

When they designed the 270 case by necking down .30-06, they lengthened the neck considerably longer than the parent case because bullets of similar weight are much longer when only 0.277 inches diameter, compared to 0.308 inches. Thus most 270 Win chambers are cut with a long leade to the start of the rifling lands.

When you form a 270 from a .30-06 your necks will be a lot shorter. This requires careful choice of cartridge overall length, depending upon the bullet you choose. This is very important if you're trying to seat the bullets out to the start of the rifling. Make sure you have enough neck to hold the bullet securely, especially if it's a hunting load.

Also, find some way of marking the base, because it will say .30-06 Sprgfld and it will be hard to distinguish visually from the parent.

I use reformed cases for practice, load workup, and breaking in a new bore. I save the good cases for field use.
 
they will be for target shooting, and i have alot of 30-06 and not many 270.
 
there should be not real preformance differnts between .270 win factory and necked downed .30-06. i used majic marker to color .270 neck downs from .30-06. this was my first venture into case reforming in the 1970's. if you can find .270 brass use them instead
 
Since I don't have a .270 Win. (and have no plans to get one), I've never converted .30-06 brass to .270...

However, I have converted .30-06 brass to .308 Win., 8x57mm Mauser, 7x57mm Mauser and to 7.65x53mm Mauser...

And, since I do have a number of .30-06 rifles, I have converted a fair number of .270 Win. cases to .30-06...:)

Forrest
 
Yep.

Oh, yeah, it works.

I'm not sure I'd try to use any for international match, or anything, but I've never bothered to do extensive accuracy testing. It works just fine. I'd want to case gage the finished product and watch the length, but yep, it'll do.

JUST BE CAREFUL not to get your resized stuff mixed with your .30 caliber stuff. :eek:
 
Shooting a lot of them "might" lead to throat erosion in the end of the .270 chamber itself.

That "might" lead to extraction problems when you shoot real full-length .270 ammo in it again.

Just something to consider.

rcmodel
 
I neck down 308 to 7mm-08. They are a hair short but stretch out. The reason I do it is I have a bunch of 308 not much 7mm and 7mm brass is higher compared to 308 family cases. I wouldn't have a problem necking down 30-06.
 
kevinm, again, it works fine.

Doesn't matter why you want to do it, that's your business.

Sure the necks will be a few thousants shorter than "normal" but it's really no problem at all. You would have to fire thousands of rounds of "short" cases to burn any ring in your chamber, if ever. None of us get concerned about any such rings being burnt into our chambers with normal length cases so don't worry about it with a few hundred rounds of short ones. Your reformed cases will eventually stretch enough anyway.
 
It "works", but there are some potential issues...

- Neck thickness: Necking down makes the necks thicker, and some brass moves in the process. I've got a Shilen barrel on one of my .270(s) that used their .305" neck reamer. Sizing brass down, such as being described, would force me into neck turning. Regular Win .270 Brass is right at .303" in the neck when loaded. If you have a tight neck, you'll need to neck turn.

- Necking Down will move some brass: It probably won't be a huge issue going from .308 to .277 (actually .002" - .004" under for neck tension should be the result), but you're almost 'wildcatting' here. As with necking down in other wildcats, you'll be moving brass. The real issue here is avoiding doughnuts at the neck-shoulder junction. Not all doughnuts are good for you ;)

- OAL, and Neck Length: The .270 spec is longer than the .30-06, mainly in the neck. You'll be several thousandths short of the 'in-spec' neck.

- Using short necked brass: RCMODEL must have been reading, and I've come across what he mentioned in stuff by Ken Waters and Dunlap. This operation was a classic case of 'use in moderation'. The short neck is supposed to cause wear in the neck area of a in spec chamber. Thhis will lead to an area that is hard to clean, and if done a lot will erode. In some cases the erosion is reported to cause the neck to flare after firing, making extraction difficult.

- The headstamp still says .30-06: It will be a PITA if these get mixed in your .30-06 brass.

It works, but it is less than ideal.

IMO, and just my $.02 here...the final product is slightly flawed. Life's too short, buy a bag or two of brass, unless you're just going to get through a hunting season.
 
Good point about stretching. After forming and firing twice, my current batch is only 11 thousandths short of 'trim to' length 2.530".

Clark, that's interesting about the .30-'03 being the possible parent of 270 Win. But I don't think we can find used .30-'03 brass cheaper than brand new 270 Win. My last bunch of once-fire 270 was $7 for 60 pieces (about 2 months ago at the gun show) and I thought that was a bit high, but I needed them. 11 cents apiece isn't bad.
 
i ran over 100 rounds of 270 brass in my 280 dies.I had to trim some to get to the right oal,Im a brass whore,I pick up all kinds of brass,some guys shoot box after box and toss the brass in the trash cans,I'll dumpster dive in a heat beat,and I also run 30-06 brass through my 280 dies too.I keep all brands seperated,I dont mix when i reload.
 
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