Peterson Brass 300 Remington Ultra Mag Unprimed Box of 50

Peterson Brass 300 Remington Ultra Mag Unprimed Box of 50
Item #:PCC300RUM50
$2.80 per piece
Buy 3 or more, save 5%! Only $132.99 per box!
Shipping: One flat fee of $12.95 per online order.
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Availability:In Stock
Due to the packaging and shipping process, case necks are often slightly dinged or bent and need to be rounded up and sized to give proper neck tension. New and/or fired cases must be full-length resized or have the expander ball of the sizing die run through the case neck prior to loading.
Read 2 Reviews

Product Information

All 50 count listings of Peterson Cartridge casings come in one of their plastic ammo boxes.

Made in the U.S.A.

Peterson Cartridge Co is committed to producing Match-Grade Brass that enables our customers to get more reloads per casing than industry average.

Warning: Only use Peterson Cartridge Co. casings in firearms in good condition, designed, marked, and chambered for this cartridge. Do not use Peterson Cartridge Co casings for “fire forming” or any other purpose other than what they were designed and tested for. Peterson retains no responsibility for the enclosed casings if they are used outside of the manufacturer’s recommendations.

This is not loaded ammunition.


WARNING: This product can expose you to Lead, which is known to the State of California to cause cancer and birth defects or other reproductive harm. For more information go to -

Read 2 Reviews - Average Rating: 4.5 stars

Good stuff

By James G. on Jul 19, 2023
Brass looks good. I will load them very soon.

Peterson 300 RUM Brass

By Travis S. on May 30, 2023
The product shipped fast and was undamaged when I received it. And the brass is very easy to prep and load.
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