Can the bullet be seated deeper in .223 reloads?

[Doug M.]

It would not surprise me if the chamber is too tight. Depending on the make, a lot of AR platforms are made outside the spec and can cause problems. Get a chamber reamer from Ned Christiansen (michiguns.com) and make sure the chamber is actually correct for a 5.56X45 round. Do not "assume" the chamber is right unless you have a Colt, FN, Daniels Defense, Sully, or BCM. I've seen staggering amounts of metal come out when a cahmber is reamed to the right size.

 

[Nevada Ed]

If the bullet is hitting the lands , your OAL is too long !!
This new rifle just has a shorter chamber spec and you need to shorten the loads
to get your old loads to work with the new rifle, no big thing.

I don't think dropping to OAL length to 2.22" will cause a big difference in pressures
and you can test these new loads to see what is happening and how POA and accuracy turns out.

I think we are over thinking this problem.