Phantom Breech Insert Size

[stockclass48]

Anyone know what the OD is for the Phantom Breech inserts where the feed tube sits? I know the ID is 8/32 but I'm in need of purchasing a drill/tap and would like to know what size drill bit and tap to get. I'm planning to install this insert on a modified kingman hammer to use as stock class. Unfortunately, the existing hole is already worn out and figured using one of these breech inserts would work. Thanks in advance!

[stockclass48]

My Kingman Hammer

[Frmrspec]

1/4-36

[superman]

can also confirm that size is correct based on ASP's website.
https://airsoldier.com/product/cci-s...hread-inserts/

[stockclass48]

Thanks so much for the help fellas! Going on Amazon now to look for an 1/4 - 36 HSS Tap

[Chuck E Ducky]

This is the way.