Stainless Steel Tumbling Pin Media - 0.255" x 0.047" (Free Shipping)

(3 reviews) Write a Review
Usually ships in 24 hours
  • Stainless Steel Tumbling Pin Media Pouch Front
  • Stainless Steel Tumbling Pin Media Pouch Back
  • Stainless Steel Tumbling Pin Media
  • Stainless Steel Tumbling Pin
  • 0.047" x 0.255"


NOTE: Due to market conditions, we are not offering our Stainless Steel Tumbling Media at this time. Thank you.


Stainless Steel Tumbling Media by guntap is the premier tumbling media to clean, deburr, and burnish all types of metal parts, especially brass cartridges used by handloaders. The pins can be used to clean brass cases with any primer pocket or flash hole size without fear of having jammed pins.

Designed to be used in a rotary or magnetic tumbler, brass cartridges come out significantly cleaner and brigher than any other cleaning method currently on the market. Vibratory tumblers are generally not recommended unless they are industrial grade and water-tight.

The key feature is the unique dimension of the pin media - 0.047” diameter by 0.255” length (tolerance < ±5%). guntap only offers this size pin since it does not get jammed in primer pockets or flash holes, making the clean-up process quick and easy.

Although the pins are compatible with almost all common brass cartridges, certain cartridges that use a 25 caliber or 6.5mm diameter projectile can have some pins stuck sideways inside the neck. Keeping cartridges unsized when cleaning will help mitigate this issue. Stuck pins don't always occur, but good handloading practice dictates that all cartridges should be inspected prior to loading.


Product Specifications

  • Created from the highest quality 302/304 stainless steel wire sourced from a US-based steel mill with certificates of conformance
  • Manufactured and packaged in the USA, helping to support the domestic economy, unlike the inferior imported stainless media found elsewhere
  • Ferromagnetic 300-series stainless steel that is attracted by a magnet (but not magnetic itself, nor is it a 400-series stainless), making for easy pick up with a rare earth magnet
  • Virtually unlimited tumbling cycles with brass cartridges, so there's no need to replenish your media due to breakdown, unlike walnut, corn cob, or ceramic media


The Ultimate Combo with Brass Shine Detergent


  • Your pouch of media will come stuffed with a sample packet of guntap's Brass Shine Detergent, the all-in-one solution that is superior to the dish detergent + lemon shine concoction (available to purchase in 1lb, 2lb, and 10lb sizes)
  • Made in Texas at guntap's manufacturing facility, Brass Shine Detergent contains a proprietary formula developed over many months of cleaning thousands of cartridges
  • Made from biodegradable ingredients, guntap's formulation contains only the necessary ingredients to make your brass (and other metals) as clean as possible with as little foam as possible
  • Works with hard and soft water, no need to add any other chemicals to your tumbler for optimal results
Brass Shine Powdered Detergent - 1 pound

Dirty and Clean 50 BMG Comparison

Usage Directions


Although each tumbling batch is unique, the below 4-step system provides general directions for getting started when using guntap Stainless Steel Tumbling Media and Brass Shine Detergent in a rotary tumbler with a 1 gallon capacity.

If you have a 1 quart tumbler, you can reduce the amount of detergent to one teaspoon. For larger tumblers (e.g. cement mixers, PVC pipe, etc..), one to two tablespoons per gallon of water is recommended.

As you perform more cleanings with the pins, you'll be able to fine tune the variables to reach the optimal result in the least amount of time.

*Do not exceed the tumbler’s maximum weight capacity otherwise premature motor failure may occur.


The 4-Step System

Back of Stainless Media Pouch

Stainless Steel Pins

Brass Shine Powdered Detergent

Clean Brass and Pins

Step 1

Place the stainless steel pins in the tumbling drum, along with your brass cartridges (or other metal parts), one tablespoon of Brass Shine, and enough water to fill the drum halfway

Step 2

Turn on the tumbler and let run for at least 45 minutes for relatively clean cartridges/parts, or up to 2 hours for heavily soiled cartridges/parts

Step 3

Turn off the tumbler and check to see if additional cleaning time is needed (replacing the water with more detergent may be necessary if the water appears very dirty)

Step 4

Once clean, thoroughly rinse the cartridges/parts, dry, and store in a sealed container, preferably with a desiccant to prevent oxidation or corrosion



Some common points to note about guntap's Stainless Steel Tumbling Media:

  • When determining how much media to purchase for a rotary tumbler, a rough guideline is to use 5 pounds of media per 1 gallon of drum volume. For quart-size drums, 1 to 1.5 pounds of media is sufficient. For 1.5 cubic foot cement mixers, 50 pounds is needed at an absolute minimum.
  • Using stainless steel pins in vibratory tumblers is not recommend unless it has an industrial grade motor with a water-tight drum. The amount of media can vary greatly, so some experimentation is needed. For magnetic tumblers, refer to the tumbler's user manual for guidelines.
  • guntap Stainless Steel Tumbling Media must meet or exceed the tight tolerances set on the diameter (<0.0005") and length (<±5%) otherwise the entire batch is rejected. The batches of media undergo dozens of tests each day and each pouch is labeled with the associated lot number. Other manufacturers have loose tolerances, no lot numbers, and most of the time, don't perform any testing on their product. 
  • guntap's media with 0.047" diameter pins prevents jamming in cartridge flash holes. Media with 0.041" pins will get jammed side-by-side in the flash hole, and can be very difficult to extract.
  • guntap Stainless Steel Tumbling Media will not rust, even when left wet or submerged in water for extended periods of time. The only time rust will appear is with ferrous contamination. This is typically the result of cleaning carbon steel parts, exposed carbon steel surfaces on the inside of the tumbling drum, or accidental magnetic pick up of carbon steel items when retrieving pins from the floor. This does not affect the cleaning performance of the media.
View AllClose

Additional Information

302/304 Stainless
0.255" (0.247" to 0.260")
FREE Brass Shine Samples:
1 pack for every 10 pounds
View AllClose

3 Reviews

  • 5

    Posted by anonymous from wisconsin on Aug 27th 2021


  • 5
    Cleans inside the case as well as the primer pockets

    Posted by Dean Sensui on Oct 17th 2020

    I did a comparison between crushed walnut shells and pin media in an RCBS tumbler on .45 Long Colt cases that were used for "cowboy" loads with Pyrodex. The cases were soaked for a half hour in a 50-50 vinegar-water mix after being decapped, and before they were run through the tumbler. The pin media did a thorough job of cleaning the cases, both inside and out, leaving no carbon or any other residue. The crushed walnut shell media, on the other hand, couldn't clean the primer pockets nor the inside of the cases. I also compared Dawn dishwashing liquid with Guntap's Brass Shine detergent. Dawn produces a lot of foam which might adversely affect the pin media's effectiveness and left some tarnishing. The Brass Shine detergent doesn't generate much foam at all, and got the cases perfectly clean in one or two hours.

  • 5
    Stainless Media

    Posted by K.C. on May 22nd 2020

    Great product! Fast shipping! Great price! Even comes with a sample of Brass Shine that works very well! What is there not to like?

View AllClose