What would be the difference between a 55gn slug fired through a 6PPC and 55gn slug through a 22PPC?
The question sounds stupid to me,(made me sound studid) It was proposed to me when I was thinking about re-barreling my 6PPC to 22PPC - the 6PPC being similar in perfornance on game as the .243

I wanted something that would not damage pelts and thought of the 22PPC.

You should be able to duplicate the figures, with both rounds using the same bullet, as the case is identical.

Could the 6PPC case/action withstand higher pressures and produce higher velocities with the little 55gn bullet relative to the 22PPC?

I don't know if this is a sensical question at all, I am just throwing thoughts around...

Thanks for you patience...

Express,

I would guess that the 6PPC w/55's is going to be a little faster than the 22PPC w/55's, all other things equal, because of the lower sectional density of the 6mm.

Regards, Bill

I get 3600 FPS out of the 55 Gr Noslers (with just a little tailwind, anyway), and the 6mm 55's have a higher B.C. than the 55 gr. 224's.

IOW's there is nothing the 22 will do that you can't get out of the 6mm. Other than being a 22. FWIW, Dutch.

Express,
I have a Sako 75 in 6 PPC and use 55gr Nosler and 58 gr Hornady Vmax amongst others upto 80gr. In both I get about 3400fps.
Given the construction of the .22 and .243 projectiles of this weight and similar velocity I think that if you did a comparison in the field the results would be the same....explosive!
Both are high velocity frangible rounds. I get about 0.25MOA at 200m with the hornady and therefore nearly always try for head shots. I mainly shoot Hares which get badly damaged if I take a chest shot. On a Roo cull last year I used 80gr Rem Corelokt projs and saw lots of damage on the roos chest shot (~3000fps) If you are not after the head then pelt damage is eliminated. Otherwise you would have to go FMJ, if available or smaller calibre, e.g. .17 Rem.

If your PPC is not shot out, stick with that and use FMJ's.
Good Luck,
Aussie Hunter