The Small Base Sizer Die is for bottleneck type cases used in tight-chambering semi-automatic, pump or lever-action firearms. The sizer resizes cases below SAAMI minimums, reducing the shoulder and body by a few thousandths. It also de-primes the case. Note: Not recommended for ammunition used in bolt-action rifles.
- Sizes brass smaller than SAAMI specs
- Bottleneck type cases semi-automatic like AR-15
- Reduces shoulder and body by a few thousandths
- De-primes the case
The RCBS Small Base Sizing Die is special in that it sizes the brass smaller than SAAMI specifications. This helps aid greater reliability in semi-automatic rifles like the AR-15 pattern rifle and more. If feeding reliability is a must in your semi-auto or if you're having chambering issues with your semi-auto - this is the sizing die for you.
FAQ
What's the difference between full-length sizing, neck sizing, and small-base sizing dies?
- Full Length Sizing Dies: Resize the entire case to SAAMI minimum dimensions; best for reliability, semi autos, or brass used in multiple rifles.
- Neck Sizing Dies: Resize only the neck; reduces the chances of case head separation and can improve accuracy in bolt action rifles fired in the same chamber.
- Small Base Dies: Resize slightly more than standard full length sizing dies; ideal for semi autos or tight chambers where feeding reliability matters most.
More Questions? Refer to the RCBS Dies FAQ
- Manual:
- Download Manual
WARNING: This product can expose you to chemicals including lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information, go to www.p65warnings.ca.gov.
