by Dick Jones
Contributing Editor
I’ve been a fan of Mossberg since high school. A high school friend bought a Mossberg 500 pump in 1968 and I was totally impressed that it had good, solid walnut wood, decent bluing, and worked flawlessly. I’ve been a Mossberg fan ever since and once went through a duck season shooting an 835 with a success ratio of one duck per two shells.
When I first saw the Mossberg JM/ Pro, I was afraid Mossberg had tried to put too much into the features and perhaps the gun might not be able to cash the check the features were writing. I was wrong. This is a great gun and, while it might not be up to the level of guns that are painstakingly modified for competition, it is certainly a great gun for the beginning three-gunner. It must work pretty well for the experienced three-gunner as well, because Jerry Miculek has used one for two years now, and the JM in the name represents his initials.
What makes the JM/Pro a great gun is that it works. It has a big operating handle, an oversized loading port for fast reloading, and a ten-round capacity with the big extended magazine. The gun works slick. The trigger isn’t up to master level standards but it’s as good or better than any semiauto I’ve shot. It’s light, with a slight amount of creep and it’s adjustable for backlash.
The polymer stock comes with a good quality recoil pad that’s soft enough to really work. There are stock spacers to allow the shooter to adjust cast and comb height. This is important when you’re shooting on the clock, because it assures you shoot where you look and manage the recoil. I used the stock spacer with the most drop and the gun still shoots a little high, for shooting clays; for stationary targets, it works fine.
The features that are required for a gun that will work for three-gun competition also make that gun an effective tactical shotgun. The large operating handle allows fast operation in the event of a failure. The extended magazine capacity allows lots of rounds available before a reload is required, and the radiused loading port and extended shell lifter make reloading the shotgun under duress faster. Mossberg is one of only a few companies who put the safety where it should be, up on the tang, where safeties have been on quality guns since the first hammerless shotguns were made.
I took the JM Pro to a two gun event at my local club and talked the Match Director into including it in one of the stages. Every shooter in the event fired it with both slugs and shot, and there wasn’t a single hiccup. Afterwards, I got raves on the event web thread and multiple emails asking where to find one. The JM Pro is still hard to find after almost two years of production, and that’s a great testimonial for a relatively new gun.
The JM Pro was designed and built as a working gun. The finish is designed for function and the parts are machined to produce a reliable gun for a competitive price. There are visible machine marks in places, and the trigger group is a bit loose in the receiver. Mossberg didn’t spend extra money on making it visually appealing and the gun isn’t super slick or really solid feeling like a gun that costs three times the price, but the point is, the JM Pro performs as well as a gun that costs three times the price.
I’ve fired mine with everything from slugs to factory 7/8 ounce target loads and there’s only been one malfunction. I had a light strike that failed to fire. After looking on some forums, we found there had been a few posts about light strikes so I had Mike Byrd, at B & B Precision Machine, install a Wolfe 10/22 spring. I haven’t seen a problem since. This happened after it was used in the Crimson Trace Midnight 3 Gun Invitational and the AR15.com Three Gun Championship at Rockcastle.
Using the gun in hardcore competition and looking at the guns used by winning competitors did inspire a few modifications to make the JM Pro a little better. I took it back to B & B Precision Machine, and had them weld up the shell lifter to extend it closer to the magazine follower. Mike also polished the shell stop and radiused it to make it a little more reliable in the loading process. In three-gun, shooting fast isn’t as important as loading fast, so Mike also opened and beveled the loading port and took a little polymer off the rear of the forend to allow loading two stacked shells at a time. All these modifications make the JM Pro a more effective tactical shotgun as well as a better three-gun piece.
Shooting the JM Pro in a competitive event is the proof in the pudding. In M3GI the stages mercifully didn’t require a lot of loading. I used a green Crimson Trace rail laser and their tactical white light. Thanks to gas operation, recoil was softer than the Benelli three-gun shotguns I’ve fired. There is a push, but it’s a gentle push without much snap. In fast strings where you shoot six or eight close targets, you will find yourself further back as you get late in the string, so leaning in for the first target is a good idea. Muzzle rise is moderate in spite of the fact there’s no porting. (Porting puts the gun in open class.) Even before the modifications, it was easy to load and the red self-illuminating sight is easy to pick up.
