OUch! Mismatch inch/metric. Sounds like that L1A1 Century was putting out. I thought you might have been talking about the Centurion STG58 that they have been putting out recently.
Yours has the big thumbhole stock?
Have you pulled out the gas piston to check it. Mine acted the same way until I pulled the piston out and found that it had bent. I replaced it with a DSA Heavy Piston and it worked like a dream from then on.
[This message has been edited by CassidyGT (edited November 02, 1999).]