Highest OG brew?

At the risk of over doing the survey thing, I’m curious what every ones highest O.G. beer has been, and what the FG ended up at. Mine was somewhere around 1.138 and finished at 1.045

Not evenclose to that.  I think the highest I’ve done is 1.120 down to 1.026.  I would have been happier if it had finished higher.

Not sure what the OG was, but very early in my brewing career, before I actually knew what the heck I was doing, I brewed a British barleywine that came out at 12%.

I made an imperial hefe at 1.114 that went down to 1.020 with WLP380.  Yummy too.

Also a barleywine from 1.113 to 1.045 with Notty.  I definitely hit the maximum alcohol tolerance on this one, as Notty is known by others to quit about 9%, which is exactly where this one ended up.  Had I known this in advance, I might have used a different yeast.  However, it still turned out very tasty.

Both of these were all-grain with double batch sparges, aiming for 1/3 runnings from mash, 1st, & 2nd sparges.  I actually hit 81% efficiency on the barleywine, believe it or not.  Of course, I also collected enough for >2 hour boils on both as well.  With only a one-hour boil, efficiency would have sucked.

My recollection is 1.12 ending at 1.045.  I way overshot my OG goal on that one.

If this high gravity was ones goal what mash temp is best to use?

A low mash temp is a good idea… but it really doesn’t matter as much as people think, either.  I mashed both of mine at about 152 F for just 40 to 60 minutes and they turned out like you see above.

Egg on the face time, I just re-tested my hydrometers cuz I got to thinkin’ that my original test was flawed on the 2nd & 3rd phases, I now think the measured O.G. of 1.124 was actually correct on the mentioned batch.
  To test the hydro’s this time I combined 3 oz of table sugar with enough water to make 1 C of solution which should an S.G. of 1.138, the previous test I started with 1 oz. of sugar & water to make 1C for the 1.046 gravity test, but for the 1.092 & 1.138 tests I added an ounce of sugar to the existing solution for each step, which meant that on the 2nd & 3rd steps there was to much water - if the proper measure is sugar and water to make a given volume, not sugar & a given volume of water.
  If someone with more smarts than me would comment on my thinking here, confirm or refute or whatever, I’d appreciate the help.
  If I’m right this time then my rant a few months ago about crappy hydrometers was some more crow I’ll have to eat.

My biggest was an all Maris Otter barleywine that went from 1.142 down to 1.024. It took about 2 years before it was drinkable, and at 3.5 years old now it is just hitting it’s prime.

I did an experiment a few years ago to try and mimic the 21% version of not your fathers root beer. It was actually a beer and was a root beer from scratch recipe. My OG was around 1.200 and FG was right around 1.056. I had to baby the beer for a few weeks by making a monster starter from Wyeast American Ale. I dumped most of the starter in, saving only a little bit to begin another hefty yeast. I used the wort from brew day to help with the second yeast build up. By the time the yeast had grown a few days, I added simple sugar (about a pound at a time mixed with enough boiled water to make a pourable slurry) I had no idea to add enzymes to the mash at the time, so I added amylase enzymes when my fermenter started bubbling slower. I heard people adding beano to their fermenters helped with additional enzymes, so I put about 2 crushed beano pills into the mix as well. Every few days I would add simple sugar and more yeast until all activity stopped. I wanted my FG to go a little lower, but the American Ale yeast was probably at its limit…so I added champagne yeast for kicks, Just to be safe that all fermentation was done. If I recall, I think I had to boil for about 3 hours too. I’m sure I made a lot of mistakes, but it was fun. It made a very hard…kind of tasted like a very malty root beer…Beer. I couldn’t drink more than a taster at a time, because it was wayyyyy too sweet still.  I enjoyed the challenge, but next time I will make a much more simple recipe to attempt anything that high. Just to make you laugh a little, this was my grain bill…err I mean sugar bill.
16 lb American - Pale 2-Row
4 lb United Kingdom - Golden Naked Oats
3 lb Honey
6 lb Corn Sugar - Dextrose
2 lb American - Caramel / Crystal 40L
2 lb Belgian Candi Syrup - Amber

My 2 big ones were:
Belgian Dark Strong 1.122 to 1.030
Parti-Gyle Wee Heavy 1.114 to 1.030
I did 5 gallons of the Wee Heavy and 16 gallons of a 4.7% Scottish Ale using 46 lbs. of grain.