Historic 'sort of' Lager

I fancy using the Crossmyloof California Common and Kolsch yeasts to produce a pseudo lager. I also fancy giving one of Ron Pattinson's historical British lager recipes a spin. Sounds like an excellent opportunity to mess around and experiment a bit.

So here is the plan.

1. The recipe.

This will be based on Rons '1934 Barclay Perkins Draught Lager' from his blog. I've scaled it to 19L in the FV, choose to use Saaz for the hops, like Kristen England, and I've also attempted to adapt the mash schedule he describes in the comments for my equipment.

1934 Barclay Perkins Draught Lager

Boil Time: 90 min
Batch Size: 19 liters (fermentor volume)
Boil Size: 22.2 liters
Boil Gravity: 1.037
Efficiency: 70% (brew house)

STATS:
Original Gravity: 1.043
Final Gravity: 1.010
ABV (standard): 4.35%
IBU (tinseth): 24.1
SRM (morey): 3.3

FERMENTABLES:
1.86 kg - United Kingdom - Lager (50%)
1.86 kg - United Kingdom - Pale 2-Row (50%)

HOPS:
25 g - Saaz, Type: Pellet, AA: 3.5, Use: Boil for 90 min, IBU: 14.03
25 g - Saaz, Type: Pellet, AA: 3.5, Use: Boil for 30 min, IBU: 10.08

MASH GUIDELINES:
1) Infusion, Temp: 51 C, Time: 40 min, Amount: 9.3 L, Use 56.4 degrees stike
2) Temperature, Temp: 70 C, Time: 20 min, Amount: 6.9 L, boiling
3) Temperature, Temp: 77 C, Time: 15 min, Amount: 5.4 L, boiling
4) Sparge, Temp: 79 C, Time: 15 min, Amount: 10.9 L, mash
Starting Mash Thickness: 2.5 L/kg

I'm undecided on the pale malt to use, but am leaning towards Golden Promise rather than Marris Otter. I'll probably change my mind on the way to the home brew shop several times.

2. The yeasts.

CML's specifications give a lower end for fermentation temperature at 15° for both yeasts. So I sent them an email asking if this could be lowered if the pitch rate was doubled. That way, I can split the 19L batch into 2, and use one packet of yeast in each. I got a really prompt response from Steve at CML explaining that the lowest they had used them at double pitch was 14° for the California Common and 12° for the Kolsch. They also recommend a 8-12 week lagering for each yeast. I've got two 'heat only' inkbirds going spare so if I can rig up two water bags with fish tank heaters I should be good to go as soon as ambient temperatures are no higher than 12°. The weather is turning here so that could be very soon.

3. The method.

I'll mash and boil & chill as per the recipe.  Then split the wort into 2 10L FV's, put them in the water baths. Both well then be left to do their thing for however long it takes for them to complete fermenting. Then they will be bottled, left to carbonate in the water baths at a slightly higher temp, probably around 18°, then stored away in a cool wintry garage for the suggested lagering time.

Hopefully, as well as producing some amazing historic almost lager, I will be able to do an honest comparison of the two yeasts too see which I prefer. I can then add historic lager recipes to the long list of beers I don't have time to brew!