TESTED: NEW Sierra TMK Bullets

Sierra Bullets has seven new Tipped MatchKing (TMK) bullets optimized for match shooting with a cult following in some hunting communities. (Sierra does not advertise or recommend TMKs for hunting.) In this video, we test two of the newest bullets across two calibers, take lab measurements, and shoot ballistics gel!

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About Sierra Tipped MatchKing Bullets

We’ve had some spectacular results with Sierra bullets, particularly with the TMKs.

This year, Sierra introduced seven new heavy-for-caliber, high BC TMK bullets.

From Sierra:

Tipped MatchKing bullets are an evolution of the MatchKing bullet, featuring an acetal resin tip designed to reduce drag and improve ballistic efficiency. The result is flatter trajectories, reduced wind drift, and reliable feeding in magazine-fed rifles—while maintaining the accuracy standards Sierra is known for. Tipped MatchKing bullets are designed for target shooting and are not recommended for most hunting applications.

I had two specific TMK bullets to test: .22 Caliber 88-Grain Tipped MatchKing bullets and 6.5mm 153-Grain Tipped MatchKing bullets.

The 6.5mm 153-grain TMKs require a 1:7.5 twist barrel or faster. The fastest 6.5mm I had on hand was a 1:8, so I couldn’t conduct relevant accuracy testing with this bullet, but I could with the .22 caliber 88-grain bullet.

I used my upgraded 224 Valkyrie with a 1:7 twist barrel, the minimum twist rate required for the new .22 caliber TMK.

I compared each of these offerings to another popular SMK in the same caliber. The G7 BC of the new .22 caliber 88-grain bullet is 0.263. The G7 BC of the popular .22 caliber 77-grain is 0.182.

The new 6.5mm 153-grain bullet has a G7 BC of 0.320, higher than the classic 6.5mm 140-grain SMK (0.264).

This is what can be expected with heavy-for-caliber, tipped bullets: greater momentum at the target and a higher BC.

Accuracy Testing

I had previously worked up a load for my 224 Valkyrie with an 88-grain Hornady ELD-M. I swapped this with the new Sierra and kept the same 23.6 grains of Varget and 2.250” COL. (Do NOT use this load data. Always consult a verified source from a manufacturer.) This 1:7 rifle is one of my early bolt-action builds on the channel. (I also previously built an AR in 224 Valkyrie.)

224 Valkyrie Rifle with the Omega 300 Suppressor (Testing conducted with Area 419 Maverick Gen 1)

I took this rifle out to the 100-yard bench with an Area 419 Maverick Gen 1 suppressor. My first shot (cold-bore, cold suppressor) was low and I observed some vertical stringing.

Once the rifle had warmed up, I fired another group. This five-shot group measured 0.384”, which I was happy with.

The entire group was a bit low, so I’d make a sight adjustment before using it regularly, but this may have been due to the suppressor addition.

The average velocity measured 2694.7 fps with a 10.0 fps SD. I’d be confident taking this rifle/ammo combination out to 1000 yards and coyote hunting.

Ballistics Gel

Though ballistics gel testing is most common for dedicated hunting bullets, we wanted to test the 6.5mm 153-grain TMK at low and high velocity to see what expansion would look like.

TMKs have developed a cult following in some varmint hunting circles, even though they were designed for competition, not for hunting.

I used my custom 6.5 Creedmoor for the low-speed test and my 6.5 Sherman Short for magnum high speed. Neither of these rifles were suited for the accuracy test as they didn’t have the optimum twist rate, but worked fine to demonstrate bullet expansion. The low velocity test represents two scenarios: hunting with a caliber at a further distance or hunting with a less powerful cartridge.

The 6.5 Creedmoor load (low velocity) had a velocity of 2633.9 fps with an 8.5” maximum wound cavity and 23” of penetration.

The 6.5 Sherman Short load (magnum velocity) measured 2898.6 fps on the Athlon chronograph with a massive 10” wound cavity and 18.5” of penetration depth. In this scenario, you are trading weight retention and penetration for more explosive expansion.

Sierra 88-gr. and 153-gr. expanded bullets with non-expanded bullet

I ran some numbers to summarize the weight retention and expansion of each bullet.

Lab Results

Kyle Shields took a series of precision measurements from a sample of ten of each bullet.

He used a FX-120i scale with a 0.02 grain resolution to weigh each bullet and precision micrometers to measure the length and diameter. Here are the results for both bullets.

Conclusion

These heavy-for-caliber, high BC new TMKs offer easy accuracy and explosive expansion. I’m eager to test some of the other bullets as well as try the 6.5mm 153-grain with a 1:7.5 twist rifle.