To anyone who’s donned the uniform and taken the ‘Unlimited Liability’ oath to defend the U.S. Constitution, this knife should look very familiar. The U.S. government awarded its first contract for the new ‘Bayonet-Knife M7’ in 1964, and more than 4 million have been made in the last fifty years. This one has been modified by cutting saw teeth into the back. I like the appearance of this sawback M7, but I wondered if those sawteeth actually made the knife more useful as a utility-survival knife . . .
A double-edged spear point isn’t the best blade shape for a general-purpose knife, unless your idea of ‘general-purpose’ includes stabbing, spearing, skewering, impaling, and maybe a second helping of stabbing. And basically nothing else.
That needle-sharp tip was ground into the blade by whatever machine shop cut the sawteeth. They ground the edge pretty sharp (even the reverse edge) but they didn’t get it very well centered. It’s sharp enough to dig splinters with, but the 6.75″ blade is way too long for such precision tasks.
The reverse edge is sharpened for the first 2.5″ from the tip, and then serrated with these aggressive-looking sawteeth along the rest of the spine. When it comes to saws, however, aggressive is as aggressive does…
And this beast turned out to be a Bambi when it came to cutting lumber. This unimpressive groove is the result of about three minutes of diligent sawing. These sawteeth might actually keep you warm in a survival situation, but it would only be from the incredible exertion of trying to saw up some firewood. When your arm went limp and your hand cramped up, you’d freeze.
Instead of wasting my strength on sawing this dry old lumber, I got much better results by simply chopping at it. The M7 doesn’t have the kind of thick, heavy blade that you’d really want in a chopping knife, but it chopped this far through fairly soft wood in about 45 seconds. Even if time isn’t of the essence, the M7 won’t be chopping up logs for your survival cabin: it barely made a dent in a green fir bough.
This M7 isn’t a great hatchet, but it’s a terrible saw. It performed fairly well as a kindling splitter when I used another big stick as a hammer, but I could only pound on the toothed section of the spine because I didn’t want to snap off the sharpened tip.
I also cut up some food with the M7, and it’s not very good at that either. Chopping vegetables is difficult because you can’t press too hard on the spine of the blade, and you don’t want to reach down into the peanut butter jar because you’ll puncture the bottom before you know it. And cleaning sticky stuff out of those serrations absolutely sucks.
All in all, it’s safe to conclude that these serrations don’t add anything to this knife’s usefulness. They might look pretty neat, but they actually make this knife less capable for the one thing it does really well: stabbing. If (God forbid) you had to stab something living, these sawteeth would get caught in its fur or clothing as you withdrew the blade, and this could make follow-up strikes more difficult.
If you’ve got an M7 bayonet sitting around, you’ve got a sturdy blade that does one thing very well: it pokes deep, deadly holes in things after your AR-15 jams or runs out of ammo. Keep it for your most dire TEOTWAWKI scenario, but don’t over-sharpen the tip and please don’t cut sawteeth into the spine.
I picked up this Imperial M7, on a whim, for about $25. Knowing what I know now, I would have spend a few more bucks for an unmodified M7. For a much more useful bayonet/utility knife, I’ve got the newer M9 and OKC-3S on my wish list.