How To Repair A Shotgun Rib
January 04, 2011
It wasn't all that many years ago that the majority of shotguns sold had plain barrels. As a kid growing up in western North Carolina, I rarely even saw a shotgun in the field with a vent rib. Those I did see belonged to local high rollers, the movers and shakers of our small town. They had the money to buy the fancy "extras" for their guns, like barrels with vent ribs. As worldly authorities on all matters pertaining to firearms at the age of 15, my buddies and I dismissed ribs as just fancy window dressing. We sure didn't have ribs on any of the assorted break-open single shots, economy pumps, and old semiautomatics we used each season.
The Remington 870 shotgun had suffered a shallow dent in its rib and was a good candidate for repair.
That's all changed now. Manufacturers put ribs on the vast majority of shotgun barrels sold in the U.S., and in fact, those plain barrels are now the exception. This is due to a number of factors. First, and perhaps most importantly, guns with vent rib barrels sell better. It seems like gun buyers have more disposable income nowadays, and the extra cost for a vent rib is not a significant factor. Also, new technology has made it faster and consequently cheaper for manufacturers to install ribs on barrels. And, finally, regardless of what my buddies and I thought years ago, a rib does make a shotgun look nicer, and it provides a nice platform for a variety of different types of front and mid-rib sights or beads.
With more and more shotguns sporting ribs, it's to be expected to run across those that have become damaged. Vented ribs are by their very nature susceptible to damage. Ribs normally consist of a relatively thin, flat bar of steel or aluminum attached to the barrel by a number of separate posts. Vent ribs can also be found that are made of a single bar of steel or aluminum in which spaces between the posts have been milled away. Both types of ribs are easily damaged.
In most cases the damage is caused by a shotgun being dropped on its rib, which generally results in a section of the rib being bent down towards the barrel. The real problem, however, arises in repairing the rib.
A rubber O-ring holds the two claws and the crosspiece (L) of the Vent Rib Tool against the shotgun's rib (C), and the elevating screw exerts gentle pressure against the tool's crosspiece as it lifts the claws and the damaged rib (R).
Over the years I have seen numerous attempts by gun owners to repair dented ribs. Seldom were they successful. Typically, the gun owner uses a tapered blade screwdriver to try to pry up the depressed section of the rib. This causes a number of problems. Because the screwdriver blade is tapered or wedge-shaped, the gun owner often inadvertently scars the barrel or the sides of the opening of the vent in the rib below the dent. In addition, the top of the rib may be twisted as it is pried up. This is due to uneven pressure being applied to the underside of the dented rib.
An Easy Fix
Dented ribs can often be repaired quite easily. All it takes is the right tool and a willingness to go slowly and work carefully. It doesn't take much in the way of tools to do this job properly. In fact, it only takes one--and it's not all that expensive.
The tool is called Murray's Vent Rib Tool. I have no idea who Murray was, or is, but his tool is truly the answer to a gunsmith's prayer. As far as I know, the only source for this amazing tool is Brownells, Dept. ST, 200 S. Front St., Montezuma, IA 50171; 800-741-0015; www.brownells.com. The tool sells for only $30, and considering the cost of a new shotgun barrel, it's well worth it!
The Vent Rib Tool consists of two claws that straddle a brass bar. The brass bar, which is about three inches long, 1/2 inch high, and 1/4 inch wide, has a milled cut out along the bottom side. A crosspiece connects the tops of the two claws. An elevating screw runs through this crosspiece and bears against the top of the brass bar. A rubber O-ring holds the two claws against the crosspiece and against the rib when the tool is used. Other than an Allen wrench to turn the elevating screw, that's all there is to it!
Once the job has been completed, there should be little evidence of the damaged rib.
How you actually use the tool will depend upon the seriousness of the damage to the vent rib. A friend gave me a Remington 870 barrel that had a fairly shallow dent in the rib at approximately the mid point of the barrel. It was a simple matter to just place the brass bar base of the Murray's Tool over the center of the dent in the rib. The bar was positioned so the milled relief cut on the bottom of the bar was centered over the mid point of the dent. The two claws attached to the crosspiece were then positioned so they hooked under the lowest point of the dented rib.
The elevating screw in the crosspiece was then turned in so it lifted the claws up. Since the claws were hooked to the underside of the dented rib, the rib also rose. It was just a matter of carefully raising the rib until it was just slightly above the normal level of the top of the rib. When the lifting screw was disengaged, the rib flexed back down just a bit. You may have to do this a couple times until you get the rib back into its correct position.
Because they engage both sides of the rib at the same time, the two claws eliminate the possibility of twisting the rib as it is raised. The lifting force is equal on both sides of the rib. This is certainly something you would never get using a screwdriver as a pry bar!
More Severe Damage
If the dent is more severe, you have to approach the job a bit differently. For example, suppose the top of the rib is touching the top of the dented barrel.
In that case you have to raise the dent in stages. You first engage the claws as close to the center of the dent as possible on the breech side of the dent. Once the claws are engaged you raise the rib just a bit, perhaps no more than 1/32 to 1/16 inch. You then move the Murray's Tool to the muzzle side of the dent and position the claws the same distance from the center point of the dent as before. Again, you raise the rib just a bit, certainly no more than 1/16 inch. You need to elevate the dented rib
just enough to allow the claws to extend under the lowest point of the dent. Once that is done you are ready for the third and final positioning of the tool.
As with the Remington 870's repairs, the Murray's Tool is placed directly over the lowest point of the dent, and the claws are engaged on either side of the rib. Make sure that neither of the claws is canted to one side or the other. They should both bear firmly and squarely against the sides of the rib. Engage the elevating screw with the Allen wrench and slowly raise the rib. Again, you will need to raise the rib just a bit above the normal level of the top of the rib. When you disengage the tool, the rib will tend to bend back down just a bit. If all goes well, even a severe dent in a rib like this can be repaired so that there is virtually no trace of the original damage.
If you're a shotgunner or a gunsmith hobbyist, the Murray's Vent Rib Tool is one of those unique, inexpensive tools that you really should have in your toolbox. I know I'm awfully glad I have one!
Until next time, good luck and good gunsmithing!