Keg Headspace And Carbonation Time

I've done some searching but haven't been able to come up with an answer to this yet. Hoping somebody here can help. I'm wondering if the amount of headspace in a keg has any impact on how long it takes to force carbonate the beer inside it.

The reason i ask is because I recently kegged a batch of pale ale. I ended up with about 7.5 gallons (don't ask how that happened) so i filled on keg full and the other about half full. They have both been under pressure (10 psi @ 36 degrees F) for over two weeks now. The full keg is carbonated perfectly. The half full keg is only about half way there. Can anybody shed some light on why that might be?

did you purge the 1/2 keg really well several times to get most of the air out? remaining air will spoil the beer in time. i don't know if it will block the CO2 but it will share contact area with the CO2 and possibly slow entry. When in this situation I always fill to 15psi making ½CO2 / ½air, then dump the pressure thru the releif valve, then repeat to get 3/4 CO2 & ¼ air, then repeat 4 or five times to get mostly CO2.

Yes, I purged the air out of the keg really well. However, (now this might just be in my head) it seems that the beer from the keg in question is a bit different from the beer in the full keg. It still isn't completely carbonated so I'll give it another couple of weeks and see how the situation changes.

Bump!

How much longer did it take?

The ½ full keg would have had more contact surface area and less distance to diffuse through to get to the botton of the keg. It should have carbed first,,,, if the headspace contained as high percent CO2 as the full keg. My guess is that it did not, and possibly by far. I think in these situations it is purge, purge, purge,,,,, and when you think you are done, purge again. CO2 is cheap. Replacing spoiled beer..... not so cheap.

it ended up taking a little over 4 weeks. I think the problem must have been that I didn't purge enough air out of the keg because the beer was a bit "funky" and I ended up dumping it.