Inconsistant starting mash temps

Made 2 BIAB recipes the other day. My steps are: heat water to 160-162* then add grains in bag, Stir, put lid on kettle and drape a blanket over it. Wait 10-15min then check temp to see if I’m at my mark which is usually 155*. Did a wheat beer with a SG that would be around 150 and all went well. Did my 2nd which was an IPA so it had more grain volume. When I checked the temp after 15min.,I was still at 160* which makes me nervous that I didn’t get all the sugars out of the grains since the temp was so high. Took lots of stirring to get temp down below 160 and stay there. Question is that because I used a higher grain volume do I need to change my starting temp. because grains will generate their own heat? Here’s the rest of my steps for potential criticism: Mash for 60min., pull bag and set in strainer, have 2 gallons of 170-180* water which is then poured over grains till I have approx. 3.75 gallons of mash. Heat to boil and add hops at various times for 60min. Hopefully have 3 gallons of wort that is cooled using a wort chiller to 80-90*, transfer to bucket and add yeast. Still new to this so always looking for suggestions.

Thanks,
Todd

Here is a calculator for strike temp. I do BIAB and my qt/lb ratio is around 2.3

http://www.rackers.org/calcs.shtml

I add water and check temperature as I am going so I creep up on the mash temp rather than blowing way past it.

Pin pointing why your temp started high would take some reviewing…. Was your kettle warmer on the second one? Your thermometer been checked? I do as Mullerbrau, sneak up on it. You could also have added cold water/ice cubes to correct it too! You’ll just watch next time to see if and what variables there are, always take detailed notes. Sneezles61 :cheers:

I now routinely conserve a half gallon jug of water at room temp that has been treated with brewing salts ready to add if needed if temps overshoot. If it turns out I don’t need it I just heat it at the end of the sparge and use it then.