How's my flame look?

I'm working on converting my 10" banjo's to low pressure propane. I drilled out the orifice to .067" and I'm getting blue tips, but just want to be sure this is about the max power I'm going to get or if I should keep tweaking. The flame seems to surge in and out a bit too. I've been using a 4" 10 psi cajun that'll shoot a flame a foot in the air, so this is a big chage.

Also-when I'm lighting it, it keeps blowing a flame back out the back of the burner as it ignites. Kind of scarry. Any ideas why?

I'm using the hose from the high pressure regulator for the banjo's from NB and a Marshall 2 stage low pressure regulator. Should I use a larger hose for low pressure?

Based on the size you listed the orifice is way small for that pressure, start with 3/32"(.094") bit and step to 7/64"(.109") if air shutter is not fully opened to get blue flame. Based on the sound in the video the gas is burning at the jet opening not on top of the burner as the mixture was way too lean and it flashed back to the jet. Start burner testing with air shutter closed and open it until flame burns blue with yellow tip, make a mark for future reference so it can be reset if it is accidently tweaked.

That's actually what I tried on my first attempt. The .094" burned similar to what I've got now, but didn't blow back when I light it. The .110" was a big, lazy red flame.

You think this is about the maximum flame I should expect with this set up? Just seems weak to me. Would I have gotten better performance out of Hurricane burners?

I was hoping to mount the other two burners this weekend, but I'm second guessing my burner plan at the moment.

Has anyone ran a high pressure regulator to the boil kettle and then stepped it down to low pressure for the automated MLT, HLT?

I solved my problem. I was using a 1/4" hose from the regulator to my burner, upgraded to 3/8" and the burner came to life. The .094" orifice size ended up being about right.