The Mosin Nagant 91/30 is an historic artifact, and a fun shooter. Inspecting the rifle, checking the headspace and firing pin depth, and removing cosmoline were covered in Parts 1 and 2. Now it’s time to tune it up. Some owners have lugged this heavyweight rifle to the range, only to discover that their 91/30 couldn’t put a round in a rain barrel at 100 feet. That’s when they start to tear the gun apart or beat it like a redheaded mule. Don’t! With just a little effort, it’s possible to wring out some extra performance from a 91/30 and make it a nice shooter . . .
A garden-variety 91/30 is not a target rifle, but it is capable of 3-4 MOA accuracy with its iron sights. So owners should be prepared to fix what ails their Mosin Nagant rifle. It’s easy. It’s part of the fun. Best of all, the rifle’s performance can be completely upgraded while leaving just about everything close to as-is.
Why is the rifle not performing? It’s probably not so much the gun as it is the set-up.
Although some 91/30s were sighted in at 100 meters, most were zeroed at the factory or arsenal for the expected battle distance of 300 meters. Sometimes 91/30s were zeroed with the pig-sticker bayonet attached, and sometimes they weren’t. Sometimes they were sighted in with light ball ammo, and sometimes they weren’t. This “is it live, or is it Memorex” system causes a lot of today’s accuracy problems with the 91/30.
We won’t be shooting our Mosins with the bayonet, and that’s issue number one. Removing the bayonet alters barrel harmonics enough so that the point of impact can vary significantly from the point of aim when the rifle is fired without it. If a 91/30 was zeroed at 300 meters with the bayonet attached, it will shoot very high at 100-200 yards without it (91/30s rarely shoot low), and it will probably shoot to one side or another, most often to the left. Both elevation and windage issues can be remedied without difficulty.
The first step, naturally, is to establish where the 91/30 is actually printing. If it’s shooting high-left or -right, then both windage and elevation will need to be adjusted. But please, resist the temptation “solve” the windage issue by attaching the bayonet. The bayonet is a bitch to attach. Removing it is harder than performing a field colonoscopy on a rabid honey badger in heat, and will mar the bluing. Moreover, the 91/30 is already long for a .30 caliber-class long gun. Attaching the bayonet lengthens the rifle by about a foot and a half, making it longer than an ex-wife’s memory. So, be smart and leave the bayonet in a closet and don’t attach it to the rifle.
Just adjust the sights. Remember the acronym FORS, which stands for “Front Opposite, Rear Same.” Drifting the front sight in the opposite direction of where the rounds should go will solve the windage problem. So, let’s get drifting.
When I can, I like to use a laser boresight before I go to the range, just to get a vague idea of how the sights are set up. There’s no point in changing something just to make things worse. I’d rather not do a lot of math and scientific voodoo when I sight in. I may use a few extra rounds, but who cares? Milsurp 7.62x54R ammo is cheap.
There is a very rough equation for the amount of adjustment required to drift the sight. It’s very rough because it doesn’t take spindrift, wind, the earth’s rotation, the tides, the Zodiac or anything else into consideration. The equation is A = (B x C) / D, where A is the distance to drift the sight (which is what we’re solving for), B is the distance off the target, C is the sight radius (using 24” for this example) and D is the distance to the target. All measurements must be in the same units – inches, feet, meters, arshins, baby steps or light-years, it makes no difference.
Let’s say that the rifle is shooting a whole foot left at 300 feet. The equation is A” = (12” x 24”) / 3600”, and the rough solution would be .08” (that’s about 1 ¼ sixteenths of an inch). Look at a ruler. It’s not a lot of drifting.
Adjusting the front sight for windage is a piece of торт. That’s “cake” in English; in German, it would be “strudel.” The front sight can be drifted the sophisticated and expensive American way or the clumsy and cheap Russian way. The American way requires the purchase of a sight adjustment tool or pusher specifically made for front rifle sights. The clever U-shaped device fits under the barrel of a pistol or rifle and cradles the sights. Turning a screw drifts the front sight incrementally in either direction, and the sight can be dialed in with pretty good precision. The cost of a sight tool for the MN 91/30 will range from $20 to $400, if one can be found. Good luck with that.
The unsophisticated Russian way requires the use of a hammer and sickle. Excuse me, I meant a hammer and a punch. You already have those, so they don’t cost a single additional kopek. You also know where to find them, right in the bottom of your tool box. If they’re not in the bottom of the box, you may have foolishly loaned them to your best friend, so don’t forget to look in the bottom of his tool box.
Place a small eraser or wood shim under the sight, which makes this imprecise method a bit more precise and less likely to damage the bluing or the desk you’re using for a backstop. Then, use the hammer and punch to persuade the sight to move in the correct direction, keeping FORS in mind. It won’t need a lot of drift, so tap the sight instead of pounding the crap out of it. Once the sight gets to moving, it moves fast. The sight will overshoot the runway, and it will take a bit of time and a few extra rounds fired to really dial in the windage, tap-tap-tapping the sight to and fro until it’s just right. At the end of the drifting process, the windage will be dialed in and the 91/30 should be shooting straight down the middle, not wide left or right. It will still be shooting high, but that will also be fixed. In fact, taking care of the elevation issue is actually easier than drifting the front sight.
The reason the rifle is shooting high relates to the 7.62x54R round. Ballistics for that hefty Russian sledgehammer depend on bullet weight, powder charge, factory of origin, country of origin, the bore diameter of the rifle in question (they do vary) and a host of additional variables. I’ll leave the science of it to Nick Leghorn because he likes that kind of stuff and he’s really good at it. I was a Liberal Arts major, so math is not my strong suit.
I have ballistic charts for the 7.62 x 54R as well as most other rifle rounds. The charts say that, as a rule of thumb, the 7.62 x 54R has a bullet arc of at least eight to twelve inches or more at 300 meters. It should now be obvious why the 91/30 shoots so high at 100 meters. It’s because that’s the way they were set up to shoot.
MN rifles that were battle-zeroed at 300 meters (about 328 yards) took into account the sizeable bullet drop from muzzle to target at that distance. At 100 yards, though, the bullet is still rising from the muzzle, impacting high by an inch or two. Add that 2 inch rise to the 8 to 12 inches of drop already built into the 300-yard zero, and the MN hits not just high at 100 yards, but embarrassingly high. Like a foot or more high. Like Lindsay Lohan high. I’m talking high.
Russian soldiers were taught to overcome that problem by adjusting their point of aim to compensate. They weren’t just good at it, they were masters at it. Then again, the soldiers were trying to put a bullet anywhere into a man-sized man, rather than dropping a round with surgical precision into a target area smaller in circumference than the base of a shot glass.
Most shooters know about “holding over.” That’s the way I was taught to shoot, way back before mil-dot reticles. Holding over is very natural, a lot like throwing a ball. The ball starts out high and drops, just like a bullet will drop over distance. With a little bit of practice, the computer that lurks between human ears dopes out the solution. Most people, given a little practice, should be able throw a ball close to a target. The same goes for shooting high and anticipating the bullet drop.
But holding under is a whole different ball game. It’s so counter-intuitive that it’s wickedly difficult to do. Holding under by more than a foot – a foot! – to hit a typical range target totally disrupts the sight picture and makes any kind of accuracy problematic, if not impossible. Making a vital hit on a deer would be extraordinarily difficult with a 12 inch under-hold. Making such a hit on a pig or other animal built lower to the ground would be out of the question, since the shooter would then be aiming at the point on the ground – which is a never-ending plane — and not the target.
In theory, elevation can be changed with the 91/30’s rear sight. It’s a great theory, but it doesn’t bear close scrutiny. Rear sight adjustment on the 91/30 is simply too coarse to zero-in at close distances, and a crapshoot to dial in at longer distances. It’s amusing and bewildering to me that elevation on a 91/30 rear sight can be adjusted out to 2000 meters. It might be possible for an exceptionally well-trained marksman to place a round at 2000 meters into a target the size of, say, the battleship Bismarck. Maybe. On a good day. But the odds of hitting a human-sized target at .50 caliber sniper distance with this rifle and its standard iron sights are off the board. It’s the kind of sucker bet that built Las Vegas. Even the brilliant WW2 Russian snipers couldn’t do it.
Back to the issue at hand. For rifles shooting way high at 100 meters, lowering the rear elevation won’t pay off. It’s the hooded front sight that needs to be adjusted. Raising the front sight lowers the point of impact, putting the rounds where they belong. The equation we used for windage works for elevation, too. To lower the point of impact by a foot at 100 yards, the sight needs to be raised (Front Opposite) by about .08”.
There are two ways to do this. There’s the American way and there’s the Russian way.
The American way requires removing the front sight, knocking out the old sight post and replacing it with a longer one machined from . . . oh what the hell, we’re not going to do anything like that. It’s too much like work.
Here’s the Russian-style quick fix, and it works great. Strip about a half-inch of insulation from a single strand of wire, such as 16-gauge lamp cord. Make sure the cut is clean and straight at both ends. Any color that stands out for the shooter will work just fine. I’ve used white and green and they both work fine. The insulation is going to be the new sight, and will be fitted tightly over the original sight post, which will not be removed.
It’s likely that the channel inside the insulation will have to be temporarily enlarged to fit over the sight post. A pointed tool like cleaning pick, ice pick or nail will do the job. Work the tool into the channel slowly until the channel is stretched out a bit, then remove the tool. Slide the insulation over the sight post. The insulation has a memory, and the channel will tighten around the post and fit very snugly. Once slipped over the sight post, the insulation will not come off by accident, and recoil will not shake it loose. However, the insulation can be easily moved or removed with fingers or a pair of needle-nose pliers.
Start zeroing with the new sight set too high, but not so high that it touches the hood. The insulation is thick and will completely cover the target, so take a six o’clock hold. A practice shot will reveal where the rifle is printing, and it may be too low. That’s fine. That can be fixed either by lowering the new sight by forcing it further down onto the sight post, by snipping a tiny bit off the tip of the insulation with scissors or an X-ACTO, or by sanding it down. While zeroing the front sight in this manner, keep the rear sight set to the closest matching mark. If the rifle is being zeroed at 100 yards, the rear sight should be set at 100 meters. The 91/30 should be on target in just a few rounds.
But as the man said, “wait, there’s more.”
Once the sight is completely zeroed at the selected distance, you may wish to dab a bit of glow paint, sight paint or nail polish at the tip to add contrast and facilitate target acquisition. A permanent marker like a Sharpie in a high-contrast color does a good job, too. Use whatever works for you to get the high-visibility you’re looking for. Yellow works great; red is bad for bullseye shooting because the color will bleed into the bullseye.
Now here’s another sneaky little trick. Add a second small dot of paint on the insulation to mark the top of the original sight post. If you can’t see the small bulge that marks the tip of the post, you’ll easily feel it through the insulation. Having two dots creates a double zero, the top one at the new distance and the lower one at the original battle zero when the rear elevation is set to 300 meters. When using the lower zero, a six o’clock hold won’t work because the top of the insulation will be obscuring the target. Instead, the little dot of paint should cover the target. It takes a bit of practice but works great. Confirm both zeroes at the range before taking the rifle into the field.
The sights are zeroed, but we’re not done. We need to check the cleaning rod. Screw it down as hard as you want, and then shake the rod. Guaranteed, it’s loose. They all are. It wiggles, it vibrates, it may be slapping the nose cap when the rifle is fired, and might throw off a shot by just enough to be really annoying. Rather than removing the cleaning rod for shooting and taking a chance on damaging or losing it, leave it in place. Throw a few turns of black plastic gaffer’s tape around the cleaning rod where it meets the nose cap dampen the vibration. Now the cleaning rod won’t rattle or vibrate. The tape will not affect the rod’s cleaning function, and the black tape is unnoticeable. Gaffer’s tape is readily removable, so once again the rifle has not been permanently altered.
The 91/30 should now be accurate enough at both 100 yards and 300 meters. If it isn’t, there’s one more thing that might be done to wring out the last bit of accuracy from the rifle while keeping it as-found. The barrel can be floated.
Some people believe that 91/30 can’t be floated because it has a hand guard cover and barrel bands. They are incorrect. Not only can the barrel be floated, but it might already have been floated by the arsenal, by the factory or in the field. Many Finnish M39 Nagants had floated barrels, and it may be that Russian armorers or even soldiers caught on and did the same to their 91/30s. Maybe it was the other way around and the Finns learned this from the Russians. Who knows. Whatever the true story might be, the fact remains that floating a 91/30 barrel is easier than you’d think and some of them come that way when they’re purchased.
Here’s the complicated field kit needed to float the barrel: the MN teardrop tool or a screwdriver, some sandpaper, a couple of sockets in 10mm and 12mm, and a crisp, new bill.
The process starts with field stripping, which is about as intellectually and physically challenging as removing the cap from a tube of toothpaste. First, if the 91/30 has its sling attached, remove the front dog collar. The rear can be left in place. Unscrew the cleaning rod and set it aside. Next, there are retaining springs underneath the barrel bands that keep the bands in place. Depress the springs using thumb pressure or the MN teardrop tool, and the barrel bands can be walked forward until they clear the hand guard cover.
The whole Mosin shooting match is held together by two tang screws. One screw is on the top toward the rear of the receiver.
Back off both screws a little, but don’t remove them. The end of the stock, like the end of the hand guard cover, is protected by a metal nose cap. The purpose of loosening the screws is to create a gap so that a crisp dollar bill can be inserted past the nose cap, between the stock and the barrel. You may also use unwaxed, flavored dental floss, which leaves the stock plaque free and tasting all minty fresh.
To float the barrel, completely remove those two tang screws. They are the only things that hold the magazine and the barrel in place. 91/30s may have shims at the tang and recoil lug. Don’t lose the shims. Note their locations and use witness marks to aid in repositioning them.
Remove the screws, the barrel and the magazine and set all the parts aside. Don’t lose the screws. The rifle is now field stripped. Use this opportunity to check for hidden dirt, carbon or cosmoline, because the sticky crud gets into everything. Remove any crap with the proper tools, patches and cleaners. Check the interior of the stock for warping and cracks. Bad or damaged wood can be the cause of pressure in the barrel. Bad wood might be irreparable, but replacement stocks – synthetic or original — can be purchased.
If the stock is in good shape, the barrel can be floated. Gritty sandpaper wrapped around a properly the sockets from your socket wrench set will do the job. Test fit each socket to be sure it fits in the channel correctly. Note that the barrel is tapered, and so is the channel that will be sanded. Because the channel is more funnel than tunnel, you’ll need more than one sized socket.
The purpose of sanding is to remove high points and smooth the channel ever so slightly, not to cut a new channel. Gently sand the high points of the wood in the area indicated by the witness marks. Work slowly and accurately. It’s not a race. Take plenty of time and don’t remove any more wood than is absolutely necessary. You may find that the wood is fine and that the high points are cosmo deposits that are still leaching out of the wood. Sand them away. There also may be a high seam anywhere that two pieces of wood join. Sanding will smooth those out in no time.
Recheck the work by replacing the barrel and mag assembly, re-tightening both screws and repeating the dollar bill test. Once the rifle passes the dollar test, pocket your money and finish the job by wiping away or vacuuming up any sawdust. Check for splinters or unnecessary roughness. If you don’t like the way the wood feels, used a finer grit of sandpaper to polish it. A tack cloth is useful but not critical for removing the last vestiges of dust.
To reassemble the rifle, re-insert the barrel and magazine assemblies into the stock. They interlace, so do this carefully. Don’t worry, it’s strudel. Turn the two tang screws a few times to get the barrel and magazine properly aligned, then screw both down tightly, alternating between the two screws for even tension. A word of advice — after shooting the rifle, check the screws as they can loosen, which will cause a 91/30 to start throwing rounds all over the place. If the accuracy of a dialed-in 91/30 suddenly goes all to crap, the screws should be the first things that get checked, especially the top tang screw.
If you’re wondering whether or not to use Loctite on the screws, I don’t encourage it. My concern is that the Loctite might end up somewhere that I don’t want it to be. Should you feel otherwise, go ahead and experiment.
Reposition the hand guard cover and slide the barrel bands into their proper positions. The barrel bands will now clamp the hand guard cover to the stock, forming a two-piece wooden tube. The barrel will float inside that tube. That’s it. That’s all anyone needs to do. Торт, da? While it’s true that the whole business can be bedded, there’s not much reason to do that and besides, the purpose of this exercise is to avoid permanent alterations. Floating the barrel is not an alteration, it’s a restoration. There’s a difference.
[Click here for Part 1]
[Click here for Part 2]
[Click here to read Chris Dumm’s review of the Mosin Nagant]