Gun Review: Mossberg 100 ATR

I walked into my gun store last week fully expecting to buy a Remington 700 in .308 Winchester. As I was walking down the aisles toward that long-touted paragon of bolt actions this little beauty caught my eye. It’s a short action bolt action rifle chambered for .308 Winchester made by Mossberg. It’s called the 100 ATR. The firearm comes with a free-floated barrel, pre-installed rails for a scope and iron sights. IRON SIGHTS! The Mossberg 100 ATR only cost a fraction of what I would have paid for a Rem 700 (and became cheaper by the second as I reminded my local gun shop owner just how much I spend on transfers there to do reviews for this site). But is it any good?

Since I actually purchased this rifle (instead of getting it on loan for testing and evaluation) I felt free to customize the rifle. As soon as I got home, I broke out the Dremel and polished off that obnoxious branding on the bolt. With the mark gone, the Mossberg 100 ATR has a Glock-like minimalist appeal—if you can call a bolt that looks like it came off a Medieval manor door “minimalist.”

I polished the action a little, but it didn’t need it. The Mossberg 100 ATR’s action feels as smooth and crisp as a Dove bar straight out of the box. Sorry RF; the Mossie’s action is as good if not better than its Remington 700 counterpart. The 100 ATR’s bolt handle seems to have a slightly more curved profile to it than the 700, which makes it feel a little better in the palm of your hand, enabling a more pleasant cycling motion when using the palm of your hand. Also like the 700, the 100 ATR has a flickable safety switch by the right thumb that doesn’t compromise your point of aim.

And that’s where the similarities stop. Well, almost . . .

Like the Rem 700, the 100 ATR has an internal magazine and a capacity of five rounds. Only four of those rounds actually fit in the ATR’s magazine, making it a 4+1 rifle (with the fifth round in the chamber). The Rem 700 has a floorplate on the magazine; the shooter can unload the magazine without cycling the action. The 100 ATR has no such thing, meaning that unloading the rifle requires the shooter to cycle all of the rounds in the magazine through the chamber. The magazine is completely internal, and uses a follower that fails to meet the description of “tilt free” in every imaginable way, which is about par for the course for bolt guns. This makes loading the ATR’s magazine a little difficult (trying to make sure not to jam it), but when you’re cycling the action and feeding from the magazine it works just fine.

The 100 ATR comes with an adjustable weight trigger. It uses something Mossberg calls their “LBA” or “Lightning Bolt Action.” See that lightning bolt there? That’s actually a little piece of metal that sticks out in front of the trigger and makes it feel more like a two stage trigger than a single stage, as you need to depress that before you can get to the trigger proper. There’s a noticeable amount of wobble in the little bit of metal, but the trigger behind it is rock steady.

The trigger proper is a single stage affair with a nice, clean break. It’s set a little heavy from the factory, but an ordinary screwdriver is all you need to dial it back. Getting the metal out of the plastic is remarkably easy; only two bolts hold the thing in place. Once the plastic is off adjusting the trigger is simple as can be.

As I mentioned at the top of the hour, the 100 ATR’s big selling points are the pre-installed iron sights and pre-mounted scope rails. With the Rem 700 you have to buy a scope, rings and mounts before you even think about heading to the range. The 100 ATR’s sights consist of a post for the front sight and a “V” cut rear sight. Aligning the sights is easy and intuitive.

In a firing position, the Mossberg 100 ATR feels a little flimsy. The lightweight plastic stock makes the gun feel much lighter than other bolt action rifles. The balance is still pretty good, but the plastic stock is hollow. Every sound and vibration is transferred down the stock and into the shooter’s ear. Despite the disturbance in the force, when firing the gun the stock feels as solid as anything I’ve ever fired.

The lightweight stock also makes the perceived recoil a little greater than the Rem 700 and other similar rifles. There’s not a lot of mass, so all of the force goes into the shooter’s shoulder. Like my Mosin Nagant, I can shoot about 60 rounds through this gun before my shoulder tries to murder me.

Using a Primary Arms 3-9x40mm scope and a few Birchwood Casey Shoot-N-C targets, I was able to eek out a 5-round 1 inch group at 50 yards (ignoring the flier, which was thanks to the Mosin Nagant M44 in the next lane). A 2 MoA rifle is still nothing to sneeze at, especially for what I paid.

In terms of potential improvements, a bipod is an excellent addition to this rifle. Some mounting options may not work (as the sling hole is molded into the plastic and not a stud like on other rifles), but a cheap Winchester bipod works just fine. Slap on a scope as well and you’ve got yourself a fine shooter.

The Mossberg 100 ATR costs as much as an AK-47 clone but shoots like a good Remington 700. If you need a value-priced bolt gun in .308 Winchester, the ATR is definitely worth a look.

Mossberg 100 ATR Rifle

Caliber: .308 Winchester (7.62×51 NATO)
Barrel: 22″, 1:10 twist
Size: 42″ overall length
Weight: 6.6 lbs.
Operation: Bolt action
Finish: Matte blue
Capacity: 4+1
MSRP: $452 (typically closer to $360 retail)

Ratings (Out of Five Stars)

Accuracy: * * *
Using a bipod I was able to get a 2 MoA group at 50 yards. Using match ammo I could probably bring that group size down to around 1 MoA. . Good enough, I’d say.

Ergonomics: * * *
Just about everything on this rifle feels right. The rifle feels good in your hands. The checkering on the stock is aggressive but not painful. It’s also light enough for hauling around for hunting. For precision shooting, however, thumbhole or pistol grip stocks are definitely the more comfortable way to go. While most of the gun feels right, the stock does feel a bit flimsy and the bolt feels a tad rough to the touch.

Ergonomics Firing: * * * *
The rifle was marked down for recoil. There is a rubber buttplate to absorb some of the force, but most of the recoil goes straight into your shoulder. Other than that I have no complaints.

Reliability: * * * *
There aren’t many things to go wrong with a bolt action. I denied it the fifth star due to concerns about the magazine follower.

Customization: * * *
The front sling mounting point is problematic for bipeds who favor bipods. It’s suitable for some of the more expensive bipods, but if you’re using the one I like from Cheaper Than Dirt that surrounds the sling swivel stud then you’re S.O.L.. The choice of weaver rails (over Picatinny) reduces the fancy optics factor, but a Dremmel fixes that pretty quick.

Overall Rating: * * *
Better rifles exist at slightly higher price point, but the 100 ATR gives them a run for their money.