1943 Garand at the range

[Patrick Chadwick]

My next trial will be to imitate the Cineshot ammo, but reduce the powder charge until the self-loading starts to become erratic, then continue at a level that ensures reliable operation. It's not wanting to save a couple of grains of powder, but rather to save my shoulder!

"until the self-loading starts to become erratic"

I tried it today.
It just didn't happen!

The full charge for Vihtavuori N140 behind a 150 gn Spitzer-type bullet would be about 53 grains. I dismantled one of the Cine-shots, and the charge was indeed 53 gn. Maybe not the same powder, but I suspect one with a similar vivacity.

Using the neck-sized cases (primers well-seated) I started at 46gn. 5 shots, no problem, group slightly lower and to the right of the factory ammo.

45gn. 5 shots. No problem. Further down and to the right.

44gn. 5 shots. No problem. Further down and to the right

43gn. 5 shots. No problem. Further down and to the right.

At which point I stopped, as this was right at the bottom of the permissible range according to the Vihtavuori reloading book.

And the rifle functioned correctly every time. Proper cycling, cases ejected to the front and right, and the clip landing almost within reach. No malfunction, even though with the last group the shots were about 30 cm lower and 20 cm to the right of the normal POI. Which means that the bullets must have been emerging from the muzzle at a velocity more appropriate to a muzzle-loader.

Why does the rifle still function flawlessly at this extremely low level? Surely because the impulse given to the operating rod remains adequate to work the action, so the longer "puff" given to the piston before the slower-moving bullet exits the muzzle must be compensating very well for the reduced pressure in the barrel.

Amazing coincidence, or brilliant design? I vote for brilliant design.

[andiarisaka]

For the time being, couldn't you move the front sight a bit to get the half minute you're after?

[Patrick Chadwick]

There is not much point in making such a fine adjustment, because the testing has been done off a sandsack. Shooting free-handed for competitions will alter the body/rifle dynamics slightly, which affects the POI, so I will make the final adjustment on the last free-handed practice before the competition.

[andiarisaka]

I'll agree with you there Patrick. I think you would find the Garand would still work ok with a charge as light as 37gr or so. Least that's around the charge of 4895 that many cast bullet shooters find full function at. Not recommending you try to go that low with jacketed though.

[Raupleminze]

I can't wait to get one of these. Nice shooting!