I would advise NOT to lubricate the cases - hatcher's notebook is full of mishaps due to soldiers lubricating rounds.
Quote Originally Posted by Eaglelord17 View Post
Sounds like your issue is with the blanks as they are fine with standard rounds.
I read the OP as they inserted empty cases and they cycled fine - not that they fired standard rounds and they cycled fine.
Check the easy things first which only require and eyeball -
- check the chambers for rust, polish if necessary,
- triple check behind the lugs. I recall m16 blanks were exceptionally suety. If your rifles have only ever been fed with blanks for decades, there could be lots of buildup in there or other critical places.
- If the blanks are indeed coated with something, perhaps try tumbling the blanks in walnut media, or burnish with steel wool.

The OP says the bolts are hard to open, not hard to pull and extract. So, I just did an experiment on all my 03s and a3s. Mark a line parallel to the case with a Sharpe. Carefully insert a fired case under the extractor, and chamber with your line on top. dry fire, and slowly open. You will notice the cartridge does not twist at all, my line was still vertical on all rifles.
A lot of things can happen with the jarring caused by firing. Worn parts, or those with heavy and hardened carbon buildup, could be misaligned in the cocking cam, creating difficulty opening.
In my experience, the fouling caused by blanks was so bad at the end of a training exercise (m16 blanks) that in subsequent training events we would purposefully not fire, and literally yell "bang" instead (and of course get in trouble for it). That s&*^ gets everywhere you least expect it...and sticks more when things are well lubricated. If not cleaned thoroughly after each firing, the extra carbon from blanks will build up and harden - and no matter how thoroughly YOU scrubbed decades later, it likely isn't coming off without special treatment - e.g. they make scrapers for ARs for this purpose in heavily fired rifles. Summary version - blank ammo is some really really exceptionally dirty stuff.
If you confirm your problem is indeed hard carbon fouling, you can try a soaking carbon cleaner, like slips 2000 http://mail.slip2000.com/slip2000_carbon_killer.php
I haven't used it, but you will find videos on the web for cleaning up muzzle brakes, and other parts that normally get this kind of buildup.