The Best Cartridge You’ve Never Heard Of
By: Brandon Buskill
The jewel that's been missing from your gun safe is a 5mm Remington Rimfire Magnum. I grew up with a 5mm rifle always close at hand and regularly shot one. Only after I got older did I realize my favorite rimfire was actually a bit of a mystery to most shooters. The majority of sportsmen I cross paths with have never heard of it.
Introduced by Remington in 1969, the 5mm had a relatively short commercial life. Two variants were available: the model 591 was magazine fed and the model 592 was tube fed. Both were discontinued in 1974. The sole ammo offering at the time was the 38 grain Power-Lokt hollow point and its production was discontinued in 1982. From the mid 1980's till 2008, ammo was so scarce and so expensive the few shooters that had loved the 5mm were forced to shelve them. At an average of $2 per shot, one could not justify its continued use. I jealously guarded about 150 rounds we had left and only shot them to check my zero or take game. So what happened? If this round is so great, as you will soon see by ballistic comparison, why would it fade away?
Have you heard the phrase "if it ain't broke, don't fix it"? Well, this is what happened to Remington. The venerable .22 WMR had already been around for nearly 10 years and was widely used. The 5mm did offer more velocity and energy at all ranges in comparison to the .22 WMR but the differences in performance were not enough to drive sales. Unlike today, sportsmen were not hung up on maximum performance. Both worked well at typical small game range. So why change? Today's shooters are a bit more inclined to read up on ballistic performance before they purchase a new weapon or ammo offering, so I feel the upcoming specs in this article will pique your interest in this spitfire round that's been around since Nixon first took office and man first stepped on the moon.
On the technical side, the 5mm is a bottle necked cartridge similar in length to the .22 WMR holding a .204 diameter bullet. As mentioned earlier, the original offering available till 1982 was a 38 grain Power-Lokt hollow point travelling at 2100 fps and delivering 372 foot pounds of energy. Fortunately, for the devotees of the 5mm, Aguila began producing 5mm ammo in 2008 and production continues today. Modern offerings are a 30 grain jacketed hollow point and a 30 grain semi-jacketed hollow point. Velocity is reported by Aguila at 2300 fps with 352 foot pounds of energy as the result. Many shooters claim to achieve speeds of 2400 fps. Regardless, either speed makes the 5mm faster than the .22 WMR and it exceeds both .22 WMR and .17 HMR in energy at all ranges.
Still, however, you may ask why should I try one? Well, if the cool factor of having a gun your friends don't have is not enough and if better performance is not enough, how about this…
You can still get ammo for it during this unprecedented nationwide shortage!!! This article was written in January 2021 during the worst ammo shortage in modern times. We are a year into it and you can still buy all the 5mm ammo you want. It's omnipresent online. Previously common .22LR, .22 WMR, and all the .17's are scarce as hens teeth but not the 5mm. Come to find out, a perk of being an obscure round is that there is no rush to gobble it up. There simply are not enough 5mm shooters to use it all. You'll spend a little extra on the gun. On Gunbroker they seem to go for $600-1000. Occasionally, you'll find one advertised in the local paper or at a flea market under $200 but this is getting rather uncommon. Ammo is available in 50 round boxes and costs vary from $23-$36 per box depending on retailer. At basically 50-70 cents per shot it is nearly twice as expensive as .17HMR or .22 WMR but you can actually find the ammo when you need it. Will we be plagued by ammo shortages in the future? Who can say? But I can rest easy in the knowledge that I can stock up on ammo as needed because the fervor just isn't there to clear the shelves of it.
The 5mm covers all the bases: it's a cool conversation piece, it performs very well in its class and you can actually find ammo for it. Combine this with enough power to cleanly take 100 yard body shots at game as large as coyote and wild turkey and being cheap enough to shoot often, you really don't have a good reason not to get one and make it a regular part of your shooting fun.
