October 9, 2022Why it’s smart to full-length size your brassCommentary by Erik Cortina Why should you fully-length size your cartridge brass? Let me explain why. I have seen it repeatedly: shooters trying to close the bolt while the wind is changing. They were so focused on getting their bolt closed and getting their rifle back on the bags, that they forgot to turn the wind switch. Bang… Eight! The 2017 Canadian Nationals was the straw that broke my back. I was paired with a young girl, and she tried really hard to close her rifle’s bolt. She would close the bolt most of the time, but sometimes she couldn’t get the round to chamber. She was primarily focused on her rifle and not the conditions. After we were done with our strings, she had five more rounds than the 15-round limit. This is a lot! I suggested to her that Full-length sizing be done with 0.002? Shoulder bump, or Controlled Full Length Sizing as I call it. I told her to not worry about losing accuracy. I explained to her that I sized full-length for all my rounds. I also asked if she noticed the smoothness of my bolt and my score. They were both great!
Controlled Full-length Sizing has not been shown to reduce brass life or improve accuracy. I find that I am able to focus more on the conditions if I don’t have too much to do with chambering or extracting rounds. It is second nature. After firing, I keep the bolt open by placing my thumb on the top of the stock and rotating my hand upwards. I reach into the box to retrieve the spent case and place it back in the ammo box. Then, I pick up another loaded round to put in the chamber. I check the conditions and then push the bolt in. I close it with my index finger and middle finger. Bolt guns *
Image courtesy Sinclair International, which stocks a variety Full-length dies.
AccurateShooter.com Editor
A quality die must be a good match for your chamber to ensure proper Full-length sizing. Whidden Gunworks offers both non-bushing and bushing FL dies for our project rifles. Whidden’s click-adjustable FL sizing die is the new, patent-pending option. This allows for precise control of shoulder bump. It works great. *For gas guns like the AR10, it may be worth increasing the shoulder bump to.003. You can do more. Some benchrest cartridges can be adjusted to.0015? Perhaps bump is the best option. But.002? It is a good starting point.
Similar Posts:Tags: Erik Cortina, Full-length Sizing, Neck Sizing, Reloading Dies, Reloading Tips, Whidden Gunworks
