Questions & Answers: A Wreck of a Remington 40-X

by
posted on August 2, 2026
** When you buy products through the links on our site, we may earn a commission that supports NRA's mission to protect, preserve and defend the Second Amendment. **
Remington’s 40-X bolt-action rifle
Remington’s 40-X bolt-action rifle was a single-shot, competition-oriented rifle.

I have always wanted a high-quality .22 target rifle, but could never afford one until just recently, when I found an old Remington 40-X single-shot rifle in pieces at an estate auction. Because it was in pieces and had no sights, the price was low enough for me to take it home.

After thoroughly cleaning the rifle, I started to make note of the parts needed and questions that arose as they materialized from my inspection. My intention is to resurrect this wreck of an old gun to tip-top shooting shape suitable for competition and to learn about its history in the process.

During my inspection, I counted 10 holes in the barrel and receiver that were vacant. I assume these holes were where the missing sights were mounted. What size screws and plugs fit these holes?

The serial number engraved on the receiver is “265XX B” located below “U.S., .22 Long Rifle” and in front of “Remington Model 40-X” also engraved on the receiver.

The letters “WBMB” are prominently stamped on the left of the barrel and the letters “REP” encircled, along with two other faint marks I am unable to make out. Can you tell me when this rifle was made by the serial number? What do the markings on the barrel mean?

The stock has two screws on either side of the fore-end with a rail extending from the trigger guard forward as far as the screws. What is the purpose of the screws and the rail? What kind of scope base fits the receiver? What kind of accuracy should I expect this rifle to be capable of?

Anything else that you could tell me about the rifle would also be greatly appreciated.

H.B. Ware, Pittsburgh, Pa.


Congratulations on your find. I predict that you will spend many pleasurable hours resurrecting this fine rifle into the precision shooter that you desire. The serial number on your rifle will not tell you the age of the rifle, but the markings on the left side of the barrel just in front of the receiver will.

The “W” in WBMB is an inspector’s mark. The “BM” is the date code for January 1965,  “B” is an assembly code and “B” as a suffix to the serial number signifies a Heavy Barrel. On the right side of the barrel is the Remington export/proof mark signified by the encircled REP. Other marks are assembly and inspection symbols that have been used during various periods over the manufacturing life of the 40-X.

The 40-X was introduced in 1955 as a replacement for the Model 37 and represented Remington’s newer answer to Winchester’s Model 52 in the competitive-shooting circles. The first 40-X rifles were based on the Remington 722 action. Remington transitioned the manufacture of the 40-X to the 700 action in 1965, maintaining many of the same features as the earlier rifles.

One of the easily recognizable features to differentiate between the two action models is the bolt handle. The Model 722-action rifles have a straight bolt handle with a round knob at the end, while Model 700-action rifles have a curved or swept bolt handle with a knurled, oval-shaped knob at the end.

The “B” suffix in your serial number indicates the gun left the factory with a 28-inch bull barrel, which usually tapered to .985 inch at the muzzle. The 40-X rifles came with standard 28-inch barrels measuring .750 inch at the muzzle as well as a few other relatively rare models such as the 24-inch Sporter version. Like most rifles of this type, there were some purpose-built with modifications made to meet the needs of the customer.

From your description, it appears that your gun originally came with Redfield Olympic sights. This is indicated by the number of holes in the barrel and receiver that are present. The size screw for these holes is the standard #6-48. Plug screws of that dimension are easily obtainable to fill the vacant holes. A standard base for a Remington 700 with #6-48 screws should get you started in mounting a target scope for optimizing the precision capabilities of the rifle.

If the bore of your barrel is unblemished, it should shoot five shots into a minute-size group (1 MOA) consistently. The quality of ammunition you use to shoot your groups plays a great part in the results you realize. If you are serious about wringing out the best performance possible from your rifle, brands like RWS, SK, Eley and Lapua all make grades of rimfire ammunition that will shoot sub-MOA in a good gun with a capable shooter.

The rail from the trigger guard forward is for attaching slings and other attachments for competition shooting. The two screws on either side of the rail in the fore-end are barrel-bedding screws used to control barrel vibration and assist in fine-tuning precision bullet placement on target. Many shooters leave the barrel freefloated in front of the receiver, but the pads on the 40-X give options not usually found in a target rifle.

If you use a quality scope and shoot quality ammo in your 40-X, you should be a formidable contender in any rimfire competition.

Latest

Woman covering rifle target
Woman covering rifle target

Why This DOJ Opinion on Handgun Ownership Matters

The DOJ Office of Legal Counsel recently released an opinion concluding that the federal ban on licensed firearms dealers selling handguns to 18-20-year-old U.S. citizens is unconstitutional.

I Have This Old Gun: Czech vz.27

Following World War I, Czechoslovakia needed to equip its new army, and one of its priorities was to select a service sidearm, which ultimately became the vz.27.

Rimfire M1 Refined: The Chiappa Bushranger

Italian manufacturer Chiappa is not afraid to take an original design and give it a modern twist. New for 2026, the company is taking its rimfire M1 carbine design one step further with the Bushranger.

TriStar Arms Celebrates 30th Anniversary

Established in 1996 by the father-and-son team of Gus and Ryan Bader, TriStar Arms has grown into one of the firearm industry’s most respected names in value-driven products.

Optic on an Optic: Why You Should Add a Red-Dot to Your LPVO

Why is it that, suddenly, it seems like everyone is running around with little red-dot sights mounted on top of low-power, variable optics? Well, it turns out there are reasons for that.

How Accurate are Today’s Rifles?

In just the last few decades, rifle accuracy has improved an astonishing amount, and our expectations have risen accordingly.

Interests



Get the best of American Rifleman delivered to your inbox.