Author Topic: 308 to 30-06 rechambering (Read 647 times)

BattleRifleG3 · « **on:** September 20, 2005, 07:53:06 PM »

Assuming action length and everything else is sufficient, would it be possible to rechamber a rifle in 308 to 30-06 without adjusting the spacing of the barrel? That is, to rechamber the barrel already mounted in the receiver without taking it farther in.

I have been told it would work but based on dimensions of the two cases it appears that the shoulder of the 308 case is wider than the 30-06 case at that point in its length. True, false?

John Traveler1 · « **Reply #1 on:** September 20, 2005, 10:05:54 PM »

It's TRUE.

Rechambering an existing .308 Winchester to .30-06 will leave a bulge in the .30-06 chamber below the shoulder. Not exactly what you want for reliable extraction. A proper conversion will require either setting the barrel back (if possible), or a new barrel.

The US Military experimented with firing .308 Winchester (7.62x51 NATO) ammunition in existing .30-06 rilfes in the late 1950's. The reason was to determine user safety if 7.62x51 was accidentally fired in M1 rifles, BAR, etc. It was found that there was no hazard to the firer because the wider shoulder of the .308 Win case gave complete obturation on firing. Whether this was by design, or by accident, I dunno.

I do know that the US Navy converted several thousand .30-06 M1 rifles to 7.62 NATO using a chamber "sleeve" and they required running a reamer into the chamber to make it accept 7.62 ammunition. I found the same thing in the two .30-06 rifles I converted to .308 Winchester.

HTH
John

ScoutMan · « **Reply #2 on:** September 21, 2005, 01:53:16 AM »

Battle,

The 308 is the ballistic twin of the 06 up through 180 gr. with today's powders.

The 06 gains an advantage (because of its greater case capacity) with 200 gr. or greater bullet weight. With the quality of bullets today (eg. partition, Bronze X, etc.) there is not much need to go beyond 180 gr.

The big advantage of the 308 is that it can be produced in a more compact and handier rifle.

My $.02

Dusty Miller · « **Reply #3 on:** September 22, 2005, 10:26:17 AM »

Its always been my understanding that the 308 Winchester was inherently more accurate than the '06. It seems to me that the smart thing to do is to stick with the more accurate chambering.