Bolt fitting question

[Bindi2]

As one who shot the 303 in target comps for a number of years to tight in head space is as bad if not worse than too loose. You will need a rim thickness gauge to make sure all the rims are the same then as the action heats up your ammo wont fit. The head space setting of minimum .064 max .074 allows for all variations of rims and heat expansion. Be aware some cartridge rims are much thinner than other manufacturers. There are other things more important than head space for accurate shooting in the Lee Enfield.