Easton Axis vs FMJ (and FMJ Max): What the Aluminum Jacket Really Changes
FMJ is an Axis-diameter carbon shaft wrapped in a 7075 aluminum jacket. At the same spine that jacket adds 1.2 to 1.8 grains per inch. On a 28 in arrow at 340 spine from a 65 lb bow, I modeled the FMJ build 50 grains heavier and 15 fps slower than the Axis build. Launch kinetic energy comes out the same, momentum is about 6% higher, FOC is 1.3 points lower, and it lands about 4 in low at 40 yards on pins set for the Axis.
Durability is a trade, not a win. In 15 ArcheryTalk threads, 15 owners said their own FMJs bent or dented and 6 said theirs never did; 4 said their Axis shafts broke or split. Easton's newer FMJ Max closes most of the weight gap: on a 28 in arrow it lands within about 11 grains of Axis at 400, 340 and 300 spine, with the jacket and a tighter straightness spec.
- +50 grFMJ over Axis on a 28 in, 340-spine shaft (11.3 vs 9.5 gpi, Easton charts)
- 15 vs 6owners whose own FMJs bent vs never bent, 315 ArcheryTalk posts, 2009–2025
- 15.9% vs 10.6%FOC at the same 459 gr: Axis with the weight up front vs FMJ (modeled)
The question keeps coming back on ArcheryTalk; one 2022 thread titled Easton FMJ vs Easton Axis ran to 43 replies, and the answers split the same way they did in 2009. So I did two things: pulled Easton's current charts for all three shafts and ran real builds through my FOC, speed and penetration engines, and read 315 posts from 224 members across 15 head-to-head threads to see what owners actually reported happening to their own arrows.
Put in your bow and arrow. You'll get the finished weight, FOC, launch speed, kinetic energy, momentum and penetration score for an Axis, an FMJ and an FMJ Max build at the same spine, plus how far the two heavier shafts land from your Axis pins. The last line shows what happens if you put FMJ's extra weight on the front of an Axis instead.
Shaft weights from Easton's published charts (Axis has a 260 where FMJ and FMJ Max have a 250). Speed from my shared compound speed model, FOC from my FOC engine, penetration score from my momentum-based model at 20 yd with a 3-blade fixed head; it's a proprietary comparison number, not a lab measurement. Drop gaps are drag-free. Assumes a 9 gr nock and three 6 gr vanes on every build. Check spine for your own setup in the carbon spine calculator.
Which One Should You Pick? The 1-Minute Decision Table
| If you want… | Pick | Why |
|---|---|---|
| A heavy arrow without adding front weight | FMJ | 1.2–1.8 gpi more than Axis at the same spine; the weight comes with the shaft. |
| The most FOC for a given total weight | Axis + a heavier insert | Put the same grains up front and FOC rises 3.7–5.3 points in my builds. |
| Arrows that survive a lot of practice and 3D | Axis | Owners reported FMJ bends far more often than Axis breaks. A bent FMJ is done. |
| Easy pulls from foam and a slick finish | FMJ or FMJ Max | Easton markets both FMJ lines for easy target pull; owners say the same. |
| Axis weight with the jacket and ±.001 in straightness | FMJ Max | Same gpi as Axis at 400, a hair heavier at 340, lighter at 300. |
| Flat trajectory to 60 yd and past | Axis or FMJ Max | FMJ lands 6–9 in low at 60 yd on Axis pins in my builds; re-sighting fixes it, but the gap between pins grows. |
How Do Axis, FMJ and FMJ Max Compare on Easton's Own Charts?
All numbers here are from Easton's current pages for the 5mm Axis, the 5mm FMJ and the 5mm FMJ Max.
| Spec | 5mm Axis | 5mm FMJ | 5mm FMJ Max |
|---|---|---|---|
| Construction | All carbon | Carbon core, 7075-alloy jacket | Carbon core, 7075-alloy jacket |
| GPI at 400 / 340 / 300 | 9.0 / 9.5 / 10.7 | 10.2 / 11.3 / 12.0 | 9.0 / 9.8 / 10.3 |
| Outside diameter at 400 | 0.264 in | 0.263 in | 0.257 in |
| Straightness | ±.003 in (Match Grade ±.001) | ±.002 in (Match Grade ±.001) | ±.001 in |
| Spines | 700–200, with a 260 | 500–250 | 400–200, with a 250 |
| Insert | 5mm HIT, 16 gr (or 55 gr stainless half-out) | 5mm HIT, 16 gr (or 25 gr aluminum half-out) | 5mm HIT, or 50 gr steel one-piece half-out |
| Nock | 5mm X Nock | 5mm X Nock, 9 gr | 5mm Microlite nock |
| Maker's pitch | “24% more kinetic energy density” than standard-diameter carbon | Penetration, easy target pull | FMJ jacket on a lighter platform, easy target pull |
From Easton's product pages, October 2026. The FMJ 250 is listed at 11.5 gpi, lighter than the FMJ 300's 12.0; that's how Easton publishes it.
Two things changed since this comparison first went around the forums. Axis is no longer the straighter shaft: Easton lists standard Axis at ±.003 in and standard FMJ at ±.002, which matches one owner in a 2017 thread who pointed out FMJ is marginally straighter than Axis, .002 vs .003. And Axis, FMJ and FMJ Max no longer share every component: FMJ Max uses Easton's 5mm Microlite nock, so a box of X nocks won't carry over to it. The HIT insert does.
What Does the Jacket Do to a Real Hunting Arrow?
It adds weight you didn't choose where to put. I built the same hunting arrow on each shaft at three common pairings (400 at 60 lb, 340 at 65 lb, 300 at 70 lb) and ran it through my speed, FOC and penetration models.
| Bow / spine | Shaft | Arrow | FOC | Launch | KE | Momentum | vs Axis pins at 40 / 60 yd | Pen. score |
|---|---|---|---|---|---|---|---|---|
| 60 lb / 400 | Axis | 395 gr | 12.3% | 264 fps | 61.3 ft·lb | 0.46 | — | 55 |
| FMJ | 429 gr | 11.3% | 255 fps | 61.6 ft·lb | 0.48 | 3.2 / 7.1 in low | 57 | |
| FMJ Max | 395 gr | 12.3% | 264 fps | 61.3 ft·lb | 0.46 | same | 55 | |
| 65 lb / 340 | Axis | 409 gr | 11.9% | 279 fps | 70.6 ft·lb | 0.51 | — | 59 |
| FMJ | 459 gr | 10.6% | 264 fps | 71.1 ft·lb | 0.54 | 4.1 / 9.2 in low | 62 | |
| FMJ Max | 417 gr | 11.6% | 276 fps | 70.7 ft·lb | 0.51 | 0.7 / 1.5 in low | 60 | |
| 70 lb / 300 | Axis | 443 gr | 11.0% | 287 fps | 80.9 ft·lb | 0.56 | — | 65 |
| FMJ | 479 gr | 10.1% | 277 fps | 81.3 ft·lb | 0.59 | 2.6 / 5.9 in low | 66 | |
| FMJ Max | 431 gr | 11.3% | 290 fps | 80.8 ft·lb | 0.56 | 0.8 / 1.8 in high | 64 |
Modeled: 28 in shaft, 100 gr fixed-blade head, 16 gr HIT insert, 9 gr nock, three 6 gr vanes, 29 in draw, 330 IBO. Momentum in slug·ft/s. Drop gaps are drag-free. Penetration score is my momentum-based comparison model at 20 yd, not a lab measurement. All builds and the matched-weight set are in the Axis vs FMJ build data (CSV).
Kinetic energy barely moves, because a heavier arrow leaves a little slower and the two cancel. What the jacket buys is momentum: 4 to 6% more in my three builds, which is what my penetration model tracks, and why the FMJ score runs 1 to 3 points higher. What it costs is FOC and trajectory. If you want the reasoning behind momentum over kinetic energy, I laid it out in momentum vs kinetic energy.
If You Want FMJ's Weight, Where Should It Go?
Up front, if FOC matters to you. An FMJ spreads its extra grains down the whole shaft, so they add weight without moving the balance point forward. Put the same grains in the front of an Axis and you get the same arrow weight, the same speed and the same momentum, with the balance point well forward. Easton sells a 5mm brass HIT break-off insert from 50 to 75 grains for exactly this kind of build.
| Spine / bow | Extra grains | Arrow | FOC, FMJ | FOC, Axis + front weight | Pen. score, FMJ / Axis + |
|---|---|---|---|---|---|
| 400 / 60 lb | +34 gr | 429 gr | 11.3% | 15.1% | 57 / 59 |
| 340 / 65 lb | +50 gr | 459 gr | 10.6% | 15.9% | 62 / 65 |
| 300 / 70 lb | +36 gr | 479 gr | 10.1% | 13.8% | 66 / 69 |
Modeled. Same total weight, launch speed, KE and momentum in each row; only where the weight sits changes.
Thirty to fifty grains up front makes a shaft act weaker. An Axis 340 that tuned with a 16 gr HIT may want a 300 once a 50 gr brass insert goes in, and the FMJ doesn't have that problem because its weight isn't up front. Run both builds through the dynamic spine calculator before you buy shafts, and check the balance in the FOC and balance point optimizer.
Whether those extra FOC points are worth anything on an animal is its own argument. My take is in how much FOC adds to penetration: it matters most on a bad hit into bone, less on a clean double-lung shot.
Which Bends or Breaks More, Axis or FMJ?
FMJ bends more often than Axis breaks, going by what owners reported about their own arrows. I read every post in 15 ArcheryTalk head-to-head threads (315 posts from 224 members, July 2009 to December 2025) and counted only first-hand reports.
The bending reports cluster around practice. One member had 7 bent out of a dozen shot into a bag target in one weekend; others describe slow wobble that shows up on a spin test after months of groups. On the other side, one hunter wrote that he'd been shooting FMJs for 15 years and never had one bend, and another went to FMJ because he kept breaking Axis. Axis failures, when owners report them, are split or mushroomed ends and shafts snapped by an animal.
The materials explain the pattern. Carbon flexes and springs back until it fractures. Aluminum yields: past a point it takes a permanent set, and a thin jacket bonded to a carbon core can't spring back on its own. So a glancing hit or a hard pull that an Axis shrugs off can leave an FMJ out of straight, and the arrow still looks fine until you spin it. A cracked carbon shaft is the more dangerous failure, though, because it can come apart on the shot. Flex and check every carbon arrow after a hard hit.
Across 315 posts (2009–2025), FMJ owners like the weight, the easy pull from foam and how it hits. The recurring complaint is bending, mostly from practice: shooting tight groups, missing into hard objects, and other people pulling their arrows at 3D shoots. Axis owners mostly report long service and few failures, and the ones that broke were usually split ends or animal damage.
Does the Aluminum Jacket Penetrate Better?
Through weight, a little. Through the surface, nobody has shown it. A common forum line is that aluminum has less friction than carbon in tissue; one owner put it as aluminum having less surface tension than carbon. I couldn't find a measurement of that for arrow shafts. The two shafts are the same diameter, so frontal area doesn't separate them either.
What I can put a number on is momentum. The FMJ builds carry 4 to 6% more, and in my penetration model that's worth 1 to 3 points out of 100. For whitetails that's inside the noise; for elk it's a small, real edge, and you can get the same momentum from an Axis by adding front weight. Check your own build in the kinetic energy, momentum and pass-through calculator.
Is FMJ Max the Best of Both?
On paper it's the answer to most of this argument. Easton launched it as the FMJ jacket on a lighter-weight platform for faster speeds or higher-FOC builds, listed at ±.001 in straightness, with the new Microlite nock. At 400 spine it's the same 9.0 gpi as Axis; at 340 it's 0.3 gpi heavier; at 300 it's 0.4 gpi lighter than Axis. It's also a hair slimmer, 0.257 in at 400 vs 0.264 for Axis.
Owner data is thin because it's new. In two 2024–2025 threads I found three first-hand reports. One built 300s for his Mathews Lift X 33 at 475 grains and called them really durable so far, though he hadn't hit anything hard yet; another got perfect flight through paper with 55 gr outserts. The third tried them and is going back to regular FMJs because the Max isn't as durable. That's three people. I'd treat FMJ Max as unproven on durability and proven on weight, which comes straight from Easton's chart.
If you're chasing speed and FOC instead, Easton's 4mm Axis Long Range runs 7.6 gpi at 400 spine and ships with 50 gr aluminum half-outs. It's a different arrow from either of these, and it needs 4mm components throughout. To set any of these beside other makers' shafts at the same spine, open them in the Arrow Comparison Engine.
Can You Swap Components Between Them?
Mostly. All three take 5mm HIT inserts and 5mm field points sized by the shaft's outside diameter; the nock is where FMJ Max differs.
| Component | Axis | FMJ | FMJ Max |
|---|---|---|---|
| 5mm HIT insert (16 gr) | Yes | Yes | Yes |
| 5mm brass HIT break-off (50–75 gr) | Yes | Yes | Check Easton's listing |
| 5mm X Nock | Yes | Yes | No, ships with Microlite nocks |
| Match Grade HIT Collar | Yes, size by spine | Yes, size by spine | Included with Match Grade |
| Half-out | 5mm stainless 55 gr, steel 75 gr | 5mm aluminum 25 gr, steel 75 gr | 50 gr steel one-piece |
From Easton's product pages. Collar and half-out sizes change by spine; check the chart for yours. The nock and insert fitment finder and the arrow nock size chart cover the rest.
For most whitetail and elk hunters, I'd shoot Axis and add weight up front if I wanted a heavier arrow. You get the same momentum as an FMJ at the same total weight, several more points of FOC, and a shaft that owners report surviving practice better. Check spine after you add the weight.
Pick FMJ if you want a heavy arrow without building one, you shoot mostly at foam where easy pulls matter, and you'll spin-test after hard hits. Pick FMJ Max if you like the jacket but don't want the weight; just know the durability reports so far are three people long.
Shoot one of these and have something to add, especially an FMJ Max report? Send it through the contact page. I'll fold real owner data into the next update.
Frequently Asked Questions
What is the difference between Easton Axis and FMJ arrows?
Axis is an all-carbon 5mm shaft. FMJ is a 5mm carbon core wrapped in a 7075-alloy aluminum jacket. At the same spine the jacket adds 1.2 to 1.8 grains per inch (9.5 vs 11.3 gpi at 340), tightens the listed straightness from plus or minus .003 to .002 in, and changes how the shaft fails: FMJ tends to bend, Axis tends to split or break.
Is Axis or FMJ better for hunting?
It depends where you want the weight. FMJ gives you a heavy arrow with no extra parts. An Axis with the same grains in a heavier insert matches its weight, speed and momentum with 3.7 to 5.3 points more FOC in my builds. Owners also report FMJ bending more often than Axis breaking.
Does FMJ penetrate better than Axis?
Slightly, through weight. In my builds an FMJ carries 4 to 6% more momentum than an Axis at the same spine, worth 1 to 3 points in my penetration model. The idea that aluminum slides through tissue with less friction is common on forums, but I couldn't find a measurement of it. An Axis with added front weight closes the gap.
Do FMJ arrows bend easily?
They can. In 15 ArcheryTalk threads, 15 members said their own FMJs bent or dented, mostly from practice, groups and hard misses, while 6 said theirs never bent. Aluminum takes a permanent set where carbon springs back, so spin-test FMJs after any hard hit.
How much heavier is FMJ than Axis?
At 400 spine FMJ is 10.2 gpi vs 9.0 for Axis, at 340 it's 11.3 vs 9.5, and at 300 it's 12.0 vs 10.7. On a 28 inch shaft that's 34 to 50 grains more, before any components.
What is Easton FMJ Max?
FMJ Max is a lighter FMJ: the same carbon core and 7075 jacket at Axis-like weights (9.0 gpi at 400, 9.8 at 340, 10.3 at 300), listed at plus or minus .001 in straightness, with Easton's 5mm Microlite nocks. Owner reports on its durability are still few.
Do Axis and FMJ use the same inserts and nocks?
Axis and FMJ both use 5mm HIT inserts and 5mm X nocks. FMJ Max also takes 5mm HIT inserts but ships with the 5mm Microlite nock, so check nocks before you mix shafts.
Hey, what's up? Burak here. Archery addict, board game geek, Daft Punk fan.