Rklenke wrote:After cleaning and lubing my first shot cycled fine. The next shot stuck the brass in the chamber where I wasn't able to extract with the charging handle. I had to drop a cleaning rod down the barrel. Since I'm firing brand new starline brass, should I run a film of dry lube on all my cases?
I wasn't able to shoot any factory ammo since I had that case stick and didn't have the cleaning rod on me.
Never Lube Cases Before Shooting! Not even dry lube.
During ignition, the cases expand against the walls of the chamber and need to cling to it until the bullet breaks the seal as it exits the muzzle, lowering that pressure. If the cases don't cling, a lot more force will be exerted upon the bolt than it was designed for. Lubricants, even a small amount, can cook off from the case heating up during ignition while being squeezed between the chamber wall and the outside of the case. The molecular components in the lube can "crack" down into adhesive solids under those extreme conditions. Ever see the plastic-like residue in a popcorn popper after many uses without cleaning them. That plastic like compound is the result of the oil "cracking" down. The buildup of those deposits, while very thin, on the chamber walls, makes it sticky and more prone to additional buildup. Its a good reason to clean the barrel at the range when you're done and it's still warm. I'm talking proven track record solvent (Read: Not CLP oil) bronze brush and tight patch repeated passes. You'll feel it when you've done enough passes. Its also why you push several dry patches through the chamber and bore,
Before shooting the rifle. Never shoot out the protective oil left in it from the last cleaning session.
Ar a COL of 2.26, 32.2gr of Lil Gun is only a 65% case fill charge. You would be much better served using a more voluminous,
slower burning powder with 300gr bullets, like H4198, H4227, even AA1680. A fast burning undercharged round can develop higher pressure, more than a stout load sometimes. This has been discussed a lot recently but bullets designed for 45 ACP use (Read: Non XTP Mag) may deform when they squeeze down to the bore dimensions as they move forward, forming a plug until the pressure increases enough to push them into compliance. That pressure spike which I might add is worse with faster burning powders, can result in the cases seizing up during extraction, even from an immaculate chamber. Under excessively high pressure, the brass is physically altered to where it doesn't shrink back enough after the pressure drops, to allow easy extraction, or doesn't shrink back at all.
There's a lot to understand about internal ballistics but fortunately there's lots information on the web at your disposal, to help get a mind's eye about what is happening in those first couple of milliseconds. Google, combined with good search terms, can do wonders. So can books.
Hoot