.30-06 and .270

[50 Shooter]

How close are these in size in their regular form?

I bought some supposedly 1x fired '06 and while I checked most as I cleaned it, sized it.... Somehow or another a couple pieces made it through and were loaded up.

So as I'm checking the fired brass I find a piece of .270 and think I just picked it up off the ground while picking up my '06 brass. Then I find another piece as I'm going through the rest of the pieces I shot.

Now the thought goes through my head and I start going through the reloads I have, sure enough I find some .270 that's been loaded as .30-06. Being more curious I drop the pieces into a case gauge for '06 ammo and it fits Perfectly. So I'm guessing that the other .270 has gone/been fired through my rifle.

The rifle is fine and so is the brass as it matches '06 brass now. So what's the deal with using .270 brass to make .30-06 brass/ammo?

 

[GooseGestapo]

.270 brass has a longer neck for a slightly longer oal than .30/06. However, if trimmed to length and sized in '06 die, it will be essentially a '06 case then.

In sorting through my older brothers brass I inherited after he passed, I found several .270 cases he'd trimmed an sized and loaded among some like branded head stamped brass (Federal). Weighing and measuring brass revealed no inconsistency between '06 and .270 stamped cases.
Hope this answered your question.

 

[gamestalker]

The biggest concern is accidentally firing a .270 cartridge in a 30-06 chamber. Other than that, the necks are shorter on 06, and when they're necked down to .270 they're a bit thicker too, which can cause pressure increases, to which I have personally experienced.

Before I had an 06 back in the day, I would commonly neck it down all the time for .270 use, but if doing so I recommend working it up from the published minimum starting charge to avoid any pressure surprises.

Now as for necking up .270 to 06, I've had no issues what so ever, it just requires some trimming obviously.

But as I touched on above, make certain you do something to reduce the risk of making the mistake unintentionally shooting the .270 in the 06. Maybe mark the case head with a black sharpie to give you a heads up.

GS

 

[Sunray]

"...using .270 brass to make .30-06 brass/ammo?..." Usually the other way around. but other than bullet diameter they're the same. If you fire a .270 in an '06 you'll get '06.
Sounds like somebody who didn't actually check it, sold you range pick up brass. The real question is how easy was resizing? The expander should not have fit.

 

[50 Shooter]

It was only a few pieces in the lot and that's why I didn't notice them when I first started processing them. They sized fine, trimmed to length, loaded without problem and shot fine.

So, I guess the stuff I have is fine as it's now basically '06 brass.

 

[Trek]

Like the others have said, check the case length after re-sizing but before loading the .270 brass. As far as shooting 270 rounds in a 30-06 (loaded with .277" diameter bullets), we have accidentally done that. I seem to cause no harm, but the bullet did not go very far past the barrel (maybe 25 to 35 yards). I certainly would not recommend this method of fire forming 270 brass to use in 30-06, but it worked for us.