Michael Eichele
Well-Known Member
No matter how many loads you have made and shot, rifles you have owned, developed loads for and tested, how old you are, and how much experiance you have, once in a while you just miss the boat and then something comes along that seems so bizzare and unexplanable. I had a potentially dangerous experiance the other day and figured out the source. Yes I felt stupid and humbled, but I wish to share this beacuse A: I have no shame and B: I hope someone else can learn from this and not find themselves in a dangerous situation.
In all the years I have been reloading and shooting and testing various rifle types and calibers, I have always re developed a load when I changes lots of powders, cases and primers. The one thing I never thought to re develop for was bullets. I always just assumed manufacturing procedures lended themselves to making concistent bullets from lot to lot unlike chemically based components.
The last couple of weeks I have been developing loads for my new barrel on my 300 RUM. I worked up slowly to find the max charges for 3 powders. All yeilded decent to good accuracy. I ran out of bullets and bought some new ones. Went home, loaded them up to the max charge, went to the range and the pressure and velocity went through the roof. 95 grains of RL-25 originally offered 3377 FPS (avg). The new velocity was 3485 with a 180 AB. It took a bit of sweat to get the bolt back. I had to reduce all my loads by 2 grains. I was scratching my head trying to figure out what happend. Finally I figured it out. I was seating my bullets .020" off the lands. The new bullets at the same OACL measument (3.740") was now .002" off the lands.
Granted, I didnt damage my rifle or myself, it could have been ugly. The lesson here is always check a new lot of bullets to see if they will be closer to the lands. Personaly, I may be seating ALL my bullets long and just shove them into the lands during chambering to avoid this problem and just work up loads with them into the lands. Not sure if I will do this or just reset my die for new bullets. More experiments are in order.
Later
In all the years I have been reloading and shooting and testing various rifle types and calibers, I have always re developed a load when I changes lots of powders, cases and primers. The one thing I never thought to re develop for was bullets. I always just assumed manufacturing procedures lended themselves to making concistent bullets from lot to lot unlike chemically based components.
The last couple of weeks I have been developing loads for my new barrel on my 300 RUM. I worked up slowly to find the max charges for 3 powders. All yeilded decent to good accuracy. I ran out of bullets and bought some new ones. Went home, loaded them up to the max charge, went to the range and the pressure and velocity went through the roof. 95 grains of RL-25 originally offered 3377 FPS (avg). The new velocity was 3485 with a 180 AB. It took a bit of sweat to get the bolt back. I had to reduce all my loads by 2 grains. I was scratching my head trying to figure out what happend. Finally I figured it out. I was seating my bullets .020" off the lands. The new bullets at the same OACL measument (3.740") was now .002" off the lands.
Granted, I didnt damage my rifle or myself, it could have been ugly. The lesson here is always check a new lot of bullets to see if they will be closer to the lands. Personaly, I may be seating ALL my bullets long and just shove them into the lands during chambering to avoid this problem and just work up loads with them into the lands. Not sure if I will do this or just reset my die for new bullets. More experiments are in order.
Later