Quote Originally Posted by bigtoe01 View Post
Dave

On one of your plug blanks machine in a 6mm deep TP, drill it 3.6mm, then using a small spot drill machine a taper to a depth of 3.5mm on the breech side then using a countersink knock off the front edge to a depth of 0.5mm....then polish it in with fine emery so smooth and round it in. Next flip the plug over and send the spot drill back in to a depth of 1.5mm so we are left with 1mm at 3.6mm.

get a boot lace and some autosol and gently polish the port to just knock off any edges pulling the bootlace thru the port.

If all the theory we are reading is correct this may end up being the ultimate port, if it is drop it in to be drawn up and get the plugs made.

Im thinking something like a 300s seal that allows the barrel to actually touch the port is the way to go or an O ring much like a posted a pic of earlier.

Also remembering that recess that gained you 20fps+ it may be worth machining the plug to 6.5mm depth for TP but the TP is 6mm with the recess 0.5mm like you did before...

I may sketch this up later

Tony any objections if I use a fine taper reamer & a small radius cutter as opposed to the spot drill & countrsink? email me the drg & I'll knock it out...What are we going to do with the other two plugs guys?...VOTE NOW........LINES CLOSE MONDAY AT MIDNIGHT! Calls cost nothing but some suggestions may be laughed at & ridiculed in public.

Okay I'll go!