300 HAMR vs 300 Blackout – Cartridge Comparison

Both these cartridges are modern-era military solutions to the 5.56 mm and 7.62 shortcomings of the late 1900s. Many people have started adopting the 300 BLK and, more recently, the 300 HAMR for hunting as they provide excellent intermediate-range hunting capabilities on small to medium animals. But which cartridge is better for the hunter – Let’s find out.

History Of 300 HAM’R

The 300 HAM’R is a relatively new cartridge, developed by Wilson Combat and introduced to the public in 2018 as an intermediate rifle cartridge. This cartridge is so new that SAAMI approval was only awarded back in 2020.

The cartridge was developed to achieve performance similar to that of the 7.62×39 in the AR platform without deviating too much from the 5.56 caliber. This round has proven to have similar capabilities to that of the .308, making it a highly powerful cartridge for the AR-15 platform.

History Of 300 Blackout

Advanced Armament Corporation (AAC) designed the 300 Blackout as a lower-power 30-caliber cartridge. The cartridge is widely used in rifles with shorter barrels as it yields increased performance compared to the 5.56mm NATO.


With SAAMI approval in 2011, the 300 Blackout was then introduced in the M4 carbine and AR-15 rifles to perform best with subsonic shooting and suppressors. The parent case of the 300 Blackout is the .223 Remington.

Main Differences Between 300 HAM’R vs 300 Blackout

picture of 300 blackout and 300 hamr ammo

1) Ballistics Comparison

Numbers don’t lie, which is why ballistic performance is where the true test lies on how effective a cartridge is. We saw this to be true in our analysis of 5.56 & 5.56 NATO. For this ballistics comparison:

  • The 300 HAM’R: We will be using 110 grains rounds with a ballistic coefficiency of 0.215, shot from a rifle with a 16.25″ barrel
  • The 300 Blackout: We will also use 110 grains rounds with a ballistic coefficiency of 0.290, shot from a rifle with a 16″ barrel


300 HAM’R:

  • 100 yds: 2,160 ft/s
  • 200 yds: 1,807 ft/s
  • 300 yds: 1,499 ft/s
  • 400 yds: 1,248 ft/s
  • 500 yds: 1,076 ft/s

300 Blackout:

  • 100 yds: 2,094 ft/s
  • 200 yds: 1,834 ft/s
  • 300 yds: 1,597 ft/s
  • 400 yds: 1,389 ft/s
  • 500 yds: 1,218 ft/s

For the smaller 110-grain round, the HAM’R takes the initial lead with a higher muzzle velocity. However, the Blackout maintains its velocity more effectively as the distance increases. We saw something similar when analyzing the 17 HMR vs 22 cartridges. Both these cartridges are able to stay supersonic up to 500-600 yards.

It is important to note that with the 150-grain bigger bullet ammunition, the HAM’R will have a much better terminal performance with more velocity. Starting with a velocity of 2,106 ft/s at 100 yards and clocking a velocity of 1,441 ft/s at 500 yards, it maintains a velocity of roughly 300 ft/s faster from muzzle to 500 yards than the 300 Blk.


300 HAM’R:

  • 100 yds: 1,140 ft-lbs
  • 200 yds: 798 ft-lbs
  • 300 yds: 549 ft-lbs
  • 400 yds: 380 ft-lbs
  • 500 yds: 283 ft-lbs

300 Blackout:

  • 100 yds: 1,071 ft-lbs
  • 200 yds: 821 ft-lbs
  • 300 yds: 623 ft-lbs
  • 400 yds: 471 ft-lbs
  • 500 yds: 362 ft-lbs

You will notice that the Blackout is able to maintain a higher kinetic energy than the HAM’R for the 110-grain rounds. However, when looking at the 150-grain rounds, the HAM’R can achieve an impressive 1,477 ft-lbs at 100 yards and still maintains a kinetic energy of above 1000 ft-lbs at 300 yards. Whereas the Blk already has less than 1000 ft-lbs of kinetic energy at 100 yards. We saw in our comparison of 2506 vs 3006 rounds just how important high kinetic energy can be!


300 HAM’R:

  • 100 yds: 0″
  • 200 yds: -6.1″
  • 300 yds: -22.9″
  • 400 yds: -55.4″
  • 500 yds: -110.3″

300 Blackout:

  • 100 yds: 0″
  • 200 yds: -6.5″
  • 300 yds: -23.4″
  • 400 yds: -54″
  • 500 yds: -102.7″

With the 150-grain bullet weights, the 300-HAM’R achieves relatively similar bullet drop results to its 110-gr lighter bullet. However, the 300 BLK has 50% more bullet drop at all distances with the heavier 150-grain bullet compared to its 110-gr bullet. Just like we saw in our analysis of the 44-40 and 30-30 ammunition, bullet drop is a major factor.

Both these cartridges have similar trajectory performance with the 110-grain bullet, and both are not suited for shooting at living targets beyond 300 yards as the bullet drop is just too unpredictable to ensure a solid shot placement.

2) Size Comparison

comparing the size of 300 hamr and 300 blackout

300 HAM’R:

  • Bullet Diameter: 0.309 in (7.8 mm)
  • Neck Diameter: 0.332 in (8.4 mm)
  • Base Diameter: 0.378 in (9.6 mm)
  • Case Length: 1.595 in (40.5 mm)
  • Overall Length: 2.26 in (57 mm)
  • Case Capacity: 26 grains
  • Max Pressure (SAAMI): 57,500 psi
  • Typical Casing Material: Brass
  • Typical Bullet Weight (gr): 110-150 grains

300 Blackout:

  • Bullet Diameter: 0.308 in (7.8 mm)
  • Neck Diameter: 0.334 in (8.4 mm)
  • Base Diameter: 0.376 in (9.6 mm)
  • Case Length: 1.368 in (40.5 mm)
  • Overall Length: 2.26 in (57 mm)
  • Case Capacity: 21 grains
  • Max Pressure (SAAMI): 55,000 psi
  • Typical Casing Material: Brass
  • Typical Bullet Weight (gr): 110-150 grains

The HAMR is a larger cartridge in case length, enabling it to have a higher powder capacity and pressure. This also allows the HAMR to have a better ballistic performance, especially with the heavier bullet weights. Just like we saw in our post on how far a 22 travels bullet weight makes a bid difference.

Both these cartridges have bullet weights ranging from 110 gr to 150 gr, with the Wilson Combat 300 HAM’R supporting 95-grain ammunition as well.

3) Price Comparison

The HAMR’s ammo is surprisingly very cost-effective, considering that Wilson Combat is the only ammunition manufacturer that makes these rounds. You can expect to pay between $1 to $2 per round. However, ammo is scarce, especially during hunting season, so it is never a bad idea to stock up on some 300 HAM’R ammo.

The Blackout is a very popular cartridge, especially for AR platform fans. Yet, the ammo cost of these rounds ranges between $1 and $4 per round.

So if you are thinking about buying one of these rifles, the huge price difference between shooting these two rounds should be considered.

4) Recoil Comparison

Even though many factors affect recoil, such as grain loads, bullet weights, etc., we know that recoil, in part, is inversely correlated to rifle weight, meaning that if the rifle weight increases, the recoil will decrease. Just like we saw in our analysis of the 308 Rem and 45-70 rounds, recoil is a big factor.

So by using a rifle weighing 8 lbs, a 300 Blackout will produce a recoil energy of 7 pounds, almost two and a half times greater than the low recoil 5.56mm round. The 300 HAM’R will produce slightly higher recoil energy, ranging between 7.2 to 8.1 pounds.

5) Which Is Best For Hunting?

Considering the ballistic performance and cost per round of both these cartridges, it is safe to say going for a 300 HAM’R Wilson Combat rifle is the best for hunting. Here’s why:

Small Game

Even though a .22 caliber round is better for shooting small critters as it is cheaper and has less recoil, the long-range capabilities of these two cartridges make them attractive alternatives, especially with hog hunting, where you need more power.

Using any of these two cartridges are excellent for small game, up until 300 yards, where the bullet drop’s effect on accuracy becomes too significant.

Medium Game

It is recommended and in many states regulated to hunt deer with a cartridge with at least 1000 ft-lb energy. For that reason alone, the 300 HAM’R is the better cartridge for hunting medium-sized game.

Using the 150-grain rounds, you will be able to ethically kill a deer up to 300 yards with the HAM’R. In comparison, the 300 BLK is limited to hunting within 100 yards.

Large game

Even though they use the popular .308-inch diameter bullet, they are not suited for big game hunting, such as elk and moose. As it is required for a cartridge to produce at least 1,500 ft-lb energy to even consider hunting large game. Both these cartridges are unable to produce that much power.

Can You Shoot 300 Blackout in 300 HAM’R

The short answer is yes, you can shoot a 300 BLK round from a HAM’R rifle. However, there are a few things to consider before trying it.

  • Case Length – The HAM’R is a larger cartridge, which means that the magazine of the HAM’R is larger. Finding a magazine that can hold both cartridges would be the way to go. Bill Wilson and the rest at Wilson Combat have designed a magazine to accommodate 300 BLK, 300 HAM’R, and .223 rounds.
  • Pressure – The Blackout shoots with less pressure than the HAM’R, thus it might have an effect on the accuracy of the rounds when shooting it from the HAM’R as the barrel was designed for HAM’R cartridges.

Which Cartridge Should I Use?

Both these cartridges are extremely accurate within 100 yards, yet the 300 Blk was designed for tactical use and delivering a heavy punch at short ranges. Thus, if you are looking for a cartridge with a more versatile platform and improved accuracy at long range, and you are not too bothered by ammo scarcity, then go for Wilson Combat’s 300 HAM’R.

Frequently Asked Questions

Is 300 Hamr the same as 300 Blackout?

Both use the .308-inch diameter bullet and have similar cartridge specs. However, the 300 HAM'R has a much larger case length and can load with more grains, thus being able to shoot with higher pressure than the 300 blk.

What is the 300 Ham R good for?

The 300 HAM'R is excellent for small to medium-sized game hunting or use in a ranch rifle and provides better performance than the 5.56mm.

How far will a 300 ham R shoot?

The 300 HAM'R can maintain a supersonic speed of up to 600 yards with supersonic loads. However, for deer hunting, the 300 Ham'r should not be shot at a distance beyond 250 yards to still ensure an ethical kill.

Is the 300 hamr good for deer hunting?

The HAM'R is an excellent cartridge for deer hunting, having a favorable bullet trajectory and delivering more than 1000 fpe worth of power within 300 yards with the 150-grain bullets.

What does Hamr stand for in guns?

HAMR stands for Heat Adaptive Modular Rifle.

Is the HAMR or RPD stronger?

The RPD can deliver a heavier punch than the 300 HAMR, but taking into consideration the rate of fire, accuracy, and other ballistic measures is important before making a final decision.

The Bottom Line

The blk is an excellent close-range cartridge and works well for both hunting within 100 yards and self-defense. However, the HAM’R, also being a well-balanced cartridge, has a much better performance than the blk and is, thus, if you are an avid hunter, then the more versatile HAM’R is the better option. Still, the 300 BLK is an excellent target-shooting cartridge, as we explain in our extensive review of the 6.5 Grendel vs 300 Blackout.

About the author

Patrick Howard

I have been working as a gunsmith for 20 years. Rain, fog, moisture, high temperature, or even snow are all the things a product must withstand in order to be recommended by me.

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