Mash efficiency issues

Ok people help me out here if you can. I keep checking my mash efficiency and seem to only get about 62%. I read some threads recently about ways to raise it so on brew day yesterday I followed one of the suggestions and did a double crush of the grain.
I used 13 lbs of grain
Mashed at 152 for 60 minutes
Batch Sparged at 160 for about 10 minutes and stirred the crap out of it, rinsed the grains twice.
Got 6.5 gallons of wort with a pre boil gravity of 1.046.
Boiled for an hr down to 5.5 gallons with a gravity of 1.059.
My beersmith says mash efficiency was 62.2 but my total efficiency was 67.0.
What efficiency should I be concerned with ,mash or total? Either way I think it's still low. Am I right?

160 sparge seems low, but I could be wrong. I heat my sparge water to 190, so that it's around 185 by the time it gets through the arm and into the grain bed. Keeps me in the 73%-75% range. I'm under the assumption the sparge needs to be higher temp to be effective.

I'd be more concerned with total since thats what is going into the fermenter. however, it looks like the difference there is cuz either your pre-boil or post-boil #s are incorrect. 6.5gals @1.046 doesnt equal 5.5gals @1.059, your pre-boil should have been around 1.05 if those volumes are correct. In any case, your efficiency is a lil low, but if its consistent I wouldnt mess around with it too much. higher efficiency doesnt equal higher quality beer.

I believe double crushing should only be done when your efficiency is good. 75%+
Double crushing will not help efficiency.

dcp27 is correct. At 1.046 pre-boil * 6.5 gallons = 299 GU divide that into 5.5 gallons and you come out with a post boil gravity of 1.054 not 1.059. So IMHO your efficiency is even lower than you have calculated. If you boiled to 5 gallons that would equal 1.059

I would go back to a single crush and mash @ no less than 1.5qt/lb.

Don't worry so much about sparge temp, you can batch sparge with water at room temp.

Hmmm, maybe my markings on my boil pot are off as far as wort volume. I'll double check that today. But my refractometer definitely said 1.059 after the boil. And 1.046 pre boil.

Did you adjust for wort temperature?

william_shakes_beer said:

Did you adjust for wort temperature?

Click to expand...

Do you have to with a refractometer? I thought that was just for using a hydrometer.

watergod said:

Do you have to with a refractometer? I thought that was just for using a hydrometer.

Click to expand...

Most (if not all ) refractometers are ATC(automaic Temperature correction)

watergod said:

Hmmm, maybe my markings on my boil pot are off as far as wort volume. I'll double check that today. But my refractometer definitely said 1.059 after the boil. And 1.046 pre boil.

Click to expand...

Well I'm just saying Gravity units will remain constant.

So 1.046 = 46gu*6.5gal=299. 5.5 gal(after boil) / 299 = 1.054.

This would actually help you to boil down to a specific gravity without constantly checking. If you start at 299 into 6.5 gallons and you want a gravity of 1.059 you can calculate that you need to boil down to 5 gal (299/5=59.8 or 1.059 almost 1.060.) But keep in mind that the volume you are seeing is not actually "the" voulme due to how the volume is larger when heated. (not to mention the trub in the bottom i.e. hot/cold break and hops)There is a calculation for that. So in reality your volume was probably 5-5.25 gal not 5.5

jetmac said:

Well I'm just saying Gravity units will remain constant.

So 1.046 = 46gu*6.5gal=299. 5.5 gal(after boil) / 299 = 1.054.

This would actually help you to boil down to a specific gravity without constantly checking. If you start at 299 into 6.5 gallons and you want a gravity of 1.059 you can calculate that you need to boil down to 5 gal (299/5=59.8 or 1.059 almost 1.060.) But keep in mind that the volume you are seeing is not actually "the" voulme due to how the volume is larger when heated. (not to mention the trub in the bottom i.e. hot/cold break and hops)There is a calculation for that. So in reality your volume was probably 5-5.25 gal not 5.5

Click to expand...

Ok I just made a measuring stick for my boil pot and realized I was off by quite a bit. My wort collection was actually 7.5 gallons and I boiled down to 6.0 gallons.

Now based on the math I just learned from you Jetmac this is what I have: 1.046 pre boil, 46*7.5=345, post boil volume is 6.0 g so 345/6.0=1.058. That's more like it!

I plugged those numbers into Beersmiith and now my mash efficiency came up to 75.4% and my total is 67%. Those numbers look a lot better!

Actually looks like for the 1.059 it was really 5.85 gallons after the boil..

Hey guys thanks a lot for the help! I've been scratching my head on what's happening with my numbers for a long time and with all your help I feel like I finally got it! Thanks again everyone!

watergod said:

Ok I just made a measuring stick for my boil pot and realized I was off by quite a bit. My wort collection was actually 7.5 gallons and I boiled down to 6.0 gallons.

Now based on the math I just learned from you Jetmac this is what I have: 1.046 pre boil, 46*7.5=345, post boil volume is 6.0 g so 345/6.0=1.058. That's more like it!

I plugged those numbers into Beersmiith and now my mash efficiency came up to 75.4% and my total is 67%. Those numbers look a lot better!

Click to expand...

Yay!!