Is it possible to resize these bullets?

[Rottentofu]

I have sized them down to .309 in one pass and loaded them in 300 BO. Work great for plinking loads with a pistol length gas system.

Could you share your load data please?

[Dark Hunt]

I've resized bullets .410 bullets to .401 on one stroke with the push through Lee die. Just use a good lube (alox, Imperial, etc.)

[Sailormilan2]

Copper plated bullets with a soft lead core. If they can be chambered in your gun, they should be able to be shot just fine. They will swage down just fine by the barrel. At the velocities that you are limited to, there should be no pressure problems.
Ruger designed their Mini 30 to be able to handle .311 bullets in their .308 barrel by putting in a tapered "leade" or throat. The Germans converted thousands of their old .318 barrels to be able to handle the new .323 bullets during the rapid expansions of WW1 by doing the same thing.
Those were with standard jacketed bullets. With the soft bullets of the plated type, there should not be a problem.

[Rottentofu]

Borrowed sizing die from a friend and loaded some dummy rounds for chambering test.



COL: 1.86"

No issue with chambering. Gonna try loading with 15.5gr of H110, which should keep velocity below 2000 fps and the powder use will still be with 3% of the minimum load.