Pushing Keggle Mash Tun to the limits?

Have any of you ever put your mash tun to the limits, where your mash tun is a keggle?

I have a keggle with one of Jay Birds false bottoms, so i lose a gallon to dead space.

I am planning on brewing a weeheavy and for an 11 gallon batch, i'm looking at 36 pounds of grain. I'lll probably do a 1 qt/pound grist ratio.

Rackers calculator shows i would need 11.88 + 1 gallon deadspace FB, 12.88 gallons of space needed total. I've done some big mashes before, but this may be pushing the limits.

Any thoughts? I think i'll be fine, but always appreciate the input on HBT.

Sure, all the time. I've had my keggle MLT within a few inches of the top many times. Even with a gallon loss to the false bottom your looking at 14.5 gallons to utilize. No worries. With my system I loose some efficiency points when I'm doing brews that big though. 4-5% usually. Just something to think about.

yeah its been a while since i did a bigger beer, and im not the best note taker. i'll be losing points mashing at 158 too, so its going to be tough.

Just did a 15 gallon batch of pumpkin ale last night with 35 lbs of grain, it was about 5 inches from the top. I mashed 1.25 qts per lb. it was the first brew in that tun I was worried I was pushing the limit but turned out great.

I just did an American strong ale with 37lbs of grain and jay bird false bottom...maxed it out. I could barely dip my paddle in it without overflowing. Lost about 5% efficiency.

I did 36lbs. in mine w a JB false bottom. I recirc with a rims. I lost a little efficency and my flow was on the slow side, but everything seemed to work out ok. I'll really know in a couple more weeks.