You have a lube problem. Short and simple, the lubricants you are using do not provide enough lubrication. I use RCBS water soluble, and I can recommend Imperial Sizing wax.
And as you suspected, this barrel has a big chamber. My bolt gun gunsmith told me that Krieger M1a barrels made a special reamer that cuts the chamber extra large in the case head. They did this for a purpose: TO ADVOID LAWSUITS.!
Kreiger does not want any lawsuits from reloaders who will have out of battery slamfires due to improperly sized ammunition.
There are a lot of reloaders who use Federal primers, size with standard dies, and don't use case gages to set up their dies. A number of these guys are very adamant that they know best. A very small number of these guys will blow their rifles to pieces, and go to court, because it has to be someone’s elses fault.
Clint’s Fowler’s opinion is that reloading for gas guns is too dangerous, and he does not recommend it. Probably influenced by the number of accidents he sees, and that he builds match rifles.
http://www.fulton-armory.com/
M1 Garand pages/Garand FAQ articles/ Reloading for gas guns
Worth reading his opinion on the matter.
BTW, this is all federal once-fired brass from a M1A with a Krieger barrel.
And as you suspected, this barrel has a big chamber. My bolt gun gunsmith told me that Krieger M1a barrels made a special reamer that cuts the chamber extra large in the case head. They did this for a purpose: TO ADVOID LAWSUITS.!
Kreiger does not want any lawsuits from reloaders who will have out of battery slamfires due to improperly sized ammunition.
There are a lot of reloaders who use Federal primers, size with standard dies, and don't use case gages to set up their dies. A number of these guys are very adamant that they know best. A very small number of these guys will blow their rifles to pieces, and go to court, because it has to be someone’s elses fault.
Clint’s Fowler’s opinion is that reloading for gas guns is too dangerous, and he does not recommend it. Probably influenced by the number of accidents he sees, and that he builds match rifles.
http://www.fulton-armory.com/
M1 Garand pages/Garand FAQ articles/ Reloading for gas guns
Worth reading his opinion on the matter.