Iv'e seen this mentioned before but cannot find the thread so I need to ask the question.
Why does one get high pressure signs and a sharp recoil with a minimum powder charge load? Signs included severely flattened primers, noticably heavy bolt lift but still able to cycle by hand. I fired 2 rounds of this batch last weekend. The batch was built to allow a new shooter the ability to shoot the rifle without getting pounded by the recoil. We wound up using Remington factory ammo.
The cartridge in question is a 308 Win. assembled as follows:
- Winchester case, new, FL sized with shoulder set back .010" Shoulder set back is out of the bag. I normally only push the shoulder .003" at the most.
- Case length is "trim to' spec
- CCI200 primer
- Varget 44.0 gn. per hodgdon manual - minimum charge.
- Sierra 155 MK set to .100 off the lands. This is the lightest .30 cal bullet I have in inventory.
The rifle is a Rem 700 BDL with the factory 24" barrel. There are approximately 670 rounds through the gun to date... never any problems with the rifle until this load. The bore and chamber are clean and unobstructed. Remington factory ammo fires fine... no pressure signs. The handloads chamber and cycle fine - no interference felt. I normally don't build light loads such as this. If anything, I'm guilty of building heavy loads that push the book limits at times.
I'm aware of problems with very light loads - under book value - but this is within the range of the published data. I don't plan on building this again and have disassembled the remaining 18 cartridges.
What I would like to understand is what happens inside the cartridge and chamber when a load like this ignites, begins to move and swell the brass and push the bullet into the rifling and down the barrel.
Could someone point me to an article that explains this or perhaps offer an explanation.
Thanks in advance
As for the new shooter, first time behind a gun other than a .22LR, the teen daughter of a neighbor who is not a shooter/hunter, she fired 16 rounds that afternoon. She put ALL 16 inside an 1 1/4" circle at about 130 yards. Most were inside a 1" circle. She has the best trigger squeeze I've seen in a while with perfect followthrough. And she's fearless of the recoil. And because the gun is almost as heavy as she is, I honestly thought she would shoot a couple rounds and stop. NO. She wanted to know if I had more ammo but I didn't. Her dad gave up after 3 rounds.