The 300 HAM’R – My Build

The picture above is what the HAM’R will look like – a 24 inch, .810 inch, full bull barrel with no taper.

I have a few winter projects started, but thought I would mention a third. I will be building a single shot in 300 HAM’R.

What’s a 300 HAM’R? Briefly, it’s a 223 Remington cartridge, necked up to hold a .308 bullet. HAM’R designer, Bill Wilson of Wilson Combat, wanted a cartridge that could be fired out of an AR-15, but it needed the punch to take down whitetails, wild pigs and the like.

You can visit his site here – Wilson Combat

There is information about the HAM’R on the web, if you want to explore it. This brief narrative is written from a Canadian perspective, but will appeal to everyone. It’s a cartridge which improves on the 7.62×39 and the 300 AAC Blackout. It has been proven by its creator on hundreds of pigs and deer on his Texas ranch.

The cartridge has the punch to get the job done. For example, with a 125 gr bullet, the 300 HAM’R has a muzzle velocity of approximately 2500 fps versus the 7.62×39. The latter manages about 2360 fps.

The picture above shows a 223 Remington on the left, (well, it’s a 6x45mm actually, which is a 223 Rem necked up to 6mm) beside a 300 HAM’R. The 300 HAM’R was designed to work best with 110 to 150 grain bullets. The sweet spot is 125 to 135 grain bullets out to about 250 yards. Gee, that’s a lot like the old timey 30-30! And it is! Call it a modern version of a great deer cartridge.

Why the HAM’R?

It’s cheap to shoot and to reload. RCBS and Lee Precision make die sets for it. Most notably, the 300 HAM’R was accepted by SAAMI, and in the US at least, ammunition is being produced to feed it.

If we see this cartridge in Canada, it will happen because bolt action rifles are produced by companies like Savage or Ruger. Although this cartridge was designed for the AR, it’s perfectly at home in a single shot or bolt action rifle. Since we cannot hunt with AR rifles, single shots or bolt actions are the only choices.

I asked Ruger if they had any plans to manufacture the HAM’R and add it to their Predator line. They said no, but would forward my letter to their design team.

They saidWe have no current plans. We appreciate your input on potential models and will share your comments with our design team!

Which I took to mean – Thanks, but it won’t happen unless we get inundated with requests. Or if Ruger’s board of directors wants it.

But it never hurts to ask, right?

In the meantime, what are the options for “other than AR15 rifles”? Well, if you live in the US, conversion kits can be ordered through Wilson Combat for the Ruger American. The barrels are button rifled, match-grade stainless steel. Each is fully pre-chambered and finished in matte black Armor-Tuff.

Each kit comes with –

1.16” 300 HAM’R® Barrel, 1-15 twist

Black Armor-Tuff Barrel Nut

Barrel Nut Wrench attachment for 1/2″ torque wrench


If you want one, you will have to talk to your gunsmith. For me, the easiest route was to order a single shot barrel for my Contender from Utah based,

Match Grade Machine

Their company produces barrels for Contender and Encore frames. They also have a sister company that makes barrels for bolt actions and others.

Preferred Barrel Blanks

They list 300 HAM’R prefit barrels. For Canadians, this is an option, if you have a donor rifle. These barrels can be imported by at least two companies. Click on the names below.

Nine 35 in Ontario

Prophet River in Alberta

I have done business with these companies, and both are reliable. Either will answer any questions you might have.

But It’s Really About the Cartridge

This is why I decided to build one.

The HAM’R uses less powder than a 30-30. With the events of the past few years, powder is harder to find. Using less for the same terminal effect is prudent.

223 brass is easier to find and cheaper than 30-30.

As well, many shooters under 50 don’t want to buy an old timey cartridge like the 30-30. It uses ancient flat nose or round nose bullet designs. And let’s face it, pointed bullets retain more energy than the blunt ones which means hunters can shoot a little farther than with a 30-30.

Fewer FN and RN bullets are being made. That doesn’t mean the 30-30 is doomed. It just means that the times, they are a changing.

Load development is easier because there are fewer suitable powders. Isn’t that a disadvantage? No. Four or five powders work well, not 12 or 15. They include AA1680, CFE BLK and some others. The 300 HAM’R case only needs 25 to 28 grains of powder to produce the same velocities as a 30-30. The 30-30 uses about five to weight grains more. That makes it faster, easier and cheaper to find powders to develop a good load.

Lead time for barrels coming from the US is about three months. I ordered a barrel on November 15th (2022), so it should be here by late February. Dies, brass and bullets are available and the cost is reasonable.

That’s all for now. More to follow. Thanks for stopping by.