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View Full Version : Did some dumb things!



Norbrat
06-01-2009, 12:58 AM
Just thought I'd share some dumb things I did recently while loading a mild .308 load, and how these things can come back to bite you.

I'm usually very careful in my reloading processes, but I took shortcuts this time.

I had cast up some bullets using a new Lee CTL312-160-2R mould but I had a few issues with it not dropping the bullets easily, so I didn't cast too many as it was a frustrating process. The mould will be Lee-mented soon!

Anyway, I was keen to try the bullets out in a mild, almost sub-sonic load, for a .308. I didn't have a bullet sizing die at the time but I figured the as cast diameter of .312 should be OK with this mild load. I also did not use gas checks.

I used some once-fired brass I had bought recently, but couldn't remember whether I'd sized it. Measuring it with some vernier calipers seemed to show that it should be OK, and the bullets were being held in the neck, so I figured all would be fine.

After some research on the net, I decided to try 10 gns of Trail Boss powder.

Normally, when loading a new style bullet, you should try an empty case with just the bullet seated in the chamber of the firearm to ensure it will chamber properly. But I find it a hassle to get the gun out of storage, then the bolt which is locked away elsewhere, so I figured it should be OK to just go a bit under the recommended maximum length of 2.875" and set it at 2.65".

Some of the bullets were only just being held in the neck, so I decided to apply a crimp.

It didn't take too long for me to have about 80 rounds loaded, and I headed of to the range to try them out.

However, the ammuniton would not chamber as easily as it should. I was able to force the bolt closed on some of the rounds, and fired those, but then I had one which stuck in the chamber.

BTW, I do not recommend you force a bolt closed on tight ammo!! The only reason I did was because I knew it was a mild load and highly unlikely that it would result in excessively high pressure. I would not NORMALLY do this!!

Anyway, the rules at the range say that no attempt be made to remove live ammo stuck in a chamber at the range. This is because there have been instances (NOT at that range!!) where stuck ammo has fired when the nose of the bullet was pounded with a cleaning rod. This has resulted in at least one death of a person standing behind the open action of the rifle.

So I took the rifle home and VERY CAREFULLY tapped the stuck round out using a cleaning rod. Again, I do not recommend anyone do this!!

It seems powder can explode it subjected to enough friction, but I figured that it would be unlikely with this load as there was still plenty of airspace between the powder and the base of the bullet. But I was extremely careful and heaved a huge sigh of relief when the cartridge finally came loose!

So what caused this? I measured the outside of the neck of the loaded cases, but they were smaller than cases fired from that rifle.

I finally pushed a bullet into the chamber throat and took some measurements. It turns out that when the case is loaded with THIS bullet in THIS rifle, it has to be no longer than 2.60"!

So I ran the remaining ammo through the bullet seater die to push the bullets in a further 0.050", and because the cases had been crimped, a small sliver of lead was shaved from the bullets.

Back to the range with the chronograph, and this time the ammo fed perfectly. The chrony showed the velocity around 1250fps, so not quite subsonic, but nevertheless a comfortable load to shoot.

But the sloppy reloading still caused one more hiccup. One of those small slivers of lead must have hit the front of the chrony as the front plastic cover suddenly flew off when I fired a shot. Close inspection showed a tiny hole in the cover, as well as a small spot of paint removed from the metal front of the chrony. Still, not a major drama and easily fixed with some glue.

Interestingly, even with this rather cavalier reloading approach, the loads are quite accurate. The group at 100 metres is around 2", smaller than the area covered by the thick reticle of the Tasco 3-9x40 scope on this rifle.

Lesson learned :roll: