Were the 1909 Argy barrels known for oversize chambers ?

I have a 7.65x53 1909 take off barrel from a carbine that I am about to fit to a Portugese Vergueiro action and when I reverse a new PPU case and fit it into the mouth of the chamber, the primer end of the case goes in about 9mm ( .357" )

The base of the case measures.468 ( 11.88mm ) while the chamber mouth measures .472 ( 12mm )....are the cases undersize ?

Is this normal for a military chamber or would the web expansion be excessive ??

Roger

try a 30/06 case

Cases are under now a days but it was a military rifle and were made a little generous . The old reload books show a .471 base . ( Norma brass listed )

You are only talking about Two thousandths of clearance all around; well within specifications of any period and perfectly fine. Look at some of the allowable tolerances between chambers and brass and you will find far greater numbers than you have. Which is normal.
I just picked a 308 at random; max chamber is allowed to be .4734. Min brass is allowed to be .4703 MINUS .008! (.4623) for a .011 slop fit.
So, you see in your case, you have a near perfect fit for factory brass.

What dpcd says...

Get your headspace and shoot it. If you're going to load your own, the once-fired will fit perfectly (neck-size only)

The 7.65 is really a great round.

The real question is, when you drop the case in mouth first, does the case protrude from the barrel? If so, how much?

Since so many of these were rechambered to .30-06, it is worth verifying the actual chambering.

If it is still chambered for the 7.65x53 then the dimensions you posted are fine.

I actually have fired hundreds of 7.62 Nato rounds out of 7.65 Argentines. You end up with a case with a very short neck.
Do not tell the "headspace" "experts" about that.

I have checked the chamber with the cartridge the correct way around.......the pointy end in the hole, I think tnats the way its supposed to go .....it is still chambered for the 'argy.......so, its all go again .

Roger