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Ed Harris: Building an accurate .22 field rifle!


(Editor's Note: Ed Harris is back! He recently sent me a big archive of his older articles, and there are some real gems in there. I'll be featuring one of these treasures every other Friday! Today Ed talks about rebarreling a .22 rifle to turn it into a budget tackdriver. Some of you may remember that I love playing with .22 rifles, and you can bet I was taking notes as I read this!)


RE-BARREL YOUR 22 BOLT ACTION AND... Make an accurate smallbore silhouette or squirrel rifle!
by C.E. 'Ed' Harris (Rev. 3-1-94)

The idea of an accurate, .22 rimfire rifle weighing 7-1/2 or 8 lbs. with scope, having the same sleek good looks and steady handling as my center-fire varmint rifles was very appealing. We could have used any quality .22 bolt-action for this project, but my Ruger M77/.22 rifle was a natural choice. It was available, and while serviceable, it was an ordinary grouper. Arlington, VA gunsmith Jim Coleman suggested a heavier barrel with SAAMI-dimensioned "Match-type" chamber, and pillar bedding and minor tuning up. The result is very satisfying, and more useful than the original rifle.

My customized Ruger is highly accurate, being capable of 3/4" 10-shot 50-yard groups with good high velocity and approaching 1/2" with the best match ammunition. (See the article "Getting the Most from Your .22 Rimfire" in the 1992 Gun Digest for more details). It weighs 7-1/2 lbs. with a hunting scope, or 8 lbs. with my 10X Unertl, handy enough for field carry when after squirrels or close-range woodchucks. It is now the most-used rifle in my gun rack. I am truly surprised that Ruger still hasn't offered a heavier-barrel M77/.22 with match chamber.

Rebarreling a sporter with a heavier barrel can be done economically if you can find a good used target rifle barrel. Used .22 target rifle barrels with bright, sharp bores, in serviceable condition, can be set back and rechambered successfully. These can often be found at gun shows for $10-40, depending upon local supply and demand, but some luck is involved.

If you know a gunsmith who rebarrels rimfire target rifles, ask him to save you a used Remington 40X, Winchester 52, BSA-Martini or Anschutz barrel. Even if it has been shot a lot, when cleaned up, carefully inspected, set back, rechambered to a SAAMI-dimensioned "match" chamber, and cut to a handy length, a used target rifle barrel will yield a stiff, accurate, 22-24" steady-holding sporter barrel which will group well.

Setting back the typical 26-28" target barrel to 22-24" barrel will remove all of a worn or eroded breech, and leaves plenty enough to cut and recrown the muzzle, giving a handy field gun which is heavy enough for proper balance. However, if you want a flyweight tack driver, this can also be done. My buddy Nick Croyle put a piece of used Hart target barrel on his M77/.22 and had Jim Coleman turn it to the proportions of a buggy whip, and that 5-1/4-lb. rifle with 19" barrel will shoot 1/2" , ten- shot bugholes at 50 yards with Eley Tenex, his squirrel load!

Rebarreling .22 rimfire bolt-actions with threaded barrels such as the Kimber 82, Remington 40X, or Winchester 52 are done much the same as a center-fire rifle, except that excessive tightening of the barrel must be avoided. Otherwise the smaller shank on the softer rimfire barrel (typically 1137 steel of Rockwell B80-90 hardness) may become constricted at the root of the thread where the barrel shoulder stops against the receiver.

For non-threaded barrels, such as Anschutz, the barrel pins must be removed to free the old barrel. The ends of the pins are often polished before bluing cheap rifles, and may be hard to see. They are obvious on Anschutz and other European match rifles.

The Ruger M77/.22 barrel is the easiest to remove, and is accomplished by removing two cap screws which hold the barrel retainer. The Ruger M77/.22 barrel is retained in the receiver by a V-block shaped retainer held by two cap screws. The retainer engages a 45 degree cut in the underside of the barrel. You can copy the old barrel fairly easily. The retainer slot can be rough cut with hacksaw and filed to final dimensions or machined in a milling machine or using the milling attachment in the lathe. The Ruger 10/.22 autoloader barrel is attached similarly, but requires careful attention to the chamber for safety reasons.

The barrel shank at the breech of non-threaded replacement barrels should be turned one half a thousandth of an inch (0.0005") less than the diameter of the barrel hole, so that it is a snug fit, without having to force it home. You should be able to insert the barrel by hand with slight resistance, pick up the action with the barrel in place, and shake it without loosening. A "forced fit" must be avoided because it may cause a constriction near the chamber which will hurt accuracy.

The looser fit of .002" less than the barrel hole, as found on factory Ruger barrels is normally satisfactory, but may influence accuracy if heavy stock fore-end pressure, common as the rifles from the factory) exerts pressure against the barrel. For that reason we prefer free floated barrels.

Nearly all .22 rimfire barrels require clearance cuts for the extractor and cartridge supports. These can be cut by hand with a hacksaw and finished with small files, but it is best if they are done in a milling machine, or using with a milling attachment in a lathe. Extractors and cartridge supports are semi-circular in shape, and factory clearance cuts are radiused, not straight as a file cut would be. These cuts are located by coating the extractor and cartridge support with lipstick or Prussian blue, and gently inserting the bolt and closing it only enough to "mark" the points of contact to show where the cuts are to be made, which then copy the factory barrel.

Best accuracy in bolt actions with a variety of ammunition requires the use of the .22 Long Rifle SAAMI-dimensioned "Match" chamber. Testing indicates that the "Match" chamber gives a truly dramatic improvement in grouping compared to the common "sporting" chamber. To prove to ourselves we took two match-chambered barrels of established accuracy and reamed them to the normal "sporting" chamber, with no other change. The average extreme spread of fifty consecutive 10-shot groups at 50 yards, firing ten groups each with five different ammunitions, actually doubled when a match chamber was enlarged with the sporting reamer!

Semi-auto .22 rifles can also be rebarreled successfully, but it is dangerous to use the tight SAAMI-dimensioned "Match" chamber in an autoloader, because it WILL slam-fire and blow case heads off. However, the typical "Sporting" .22 LR chamber is too large in diameter, and also too long for best accuracy. In an autoloader the "Winchester 52D-Type" chamber (discussed in my article "Building an Accurate .22 Autoloader" in the 1993 Gun Digest) is what you should use. If you plan to do all types of.22 rimfires, boltguns, autoloaders and handguns and only want to buy one reamer, get the "Winchester 52D-Type." JGS Precision, 1141 South Sumner Road, Coos Bay, OR 97420 can provide these.

If the barrel is to be pinned permanently in place, rather than using a Ruger-type retainer, first cement it in place with "service removable" (Blue #241) Loctite prior to function test firing to ensure the extractor slots line up and do not bind on the bolt. This permits brief test firing and removal for adjustments, if needed. Once feeding and extraction are proven reliable, use the existing barrel pin holes in the receiver as guides to drill and ream new holes for somewhat larger straight pins, or tapered pins to secure the barrel.

The Ruger M77/.22 magazine feeds rounds almost straight into the chamber and requires only minimal breaking of sharp edges on the chamber entrance. A crowning ball with 320 grit abrasive works well to just remove the wire edge. On other makes of rifles which tend to shave lead, chamfering of the chamber entrance must not be over-done, lest it cause bulged case heads, which may cause burst cases, risking personal injury!

I have have found that almost all .22 sporters group more consistently when the barrel is free floated. It is also necessary to ensure that the receiver is evenly supported. If the rifle shoots tight, round groups without significant change in point of impact as the barrel heats and after taking the action in and out of the stock several times, the bedding should not be changed. Otherwise, "pillar bed" the action exactly as done for a center-fire rifle.

This is done by machining through the stock screw holes with a 3/8" drill or end mill, and fitting brass or aluminum bushings which are epoxied in place. Using metal bushings avoid the possibility of shrinkage voids which may occur when trying to "pillar" the guard screw holes with bedding compound. Solid pillar bedding positively prevents wood compression when the screws are drawn snug, holds the action in alignment without bending or twisting, and ensures free clearance of the action screws in the stock so they work in tension, as intended, rather than applying a shear force to the receiver.

Scope bases must be firmly attached. We prefer either Ruger rings on the M77/.22, or Unertl Posa-Mount bases with Unertl external adjustment scopes. Scope rings for internal adjustment scopes should be lapped after mounting on the receiver, to correct for any machining irregularities in the scope bases or rifle receiver. This ensures that the scope tube is not bent or misaligned when the mounts are drawn up snug.

Lapping of scope rings is done by turning a bar of round mild steel, brass or aluminum to .998" diameter on centers and about 10" long. The lower halves of the scope rings are firmly attached to the bases in the normal manner, then lapped with 240 grit to obtain at least 2/3 surface contact.

As for choosing the scope itself, years of experience in the Virginia Blue Ridge on squirrels has proven the value of a 6X scope on small game rifle. For a hunting rifle we suggest having the parallax corrected for 50 yards, but smallbore silhouette shooters should have it optimized for the 75m turkey, which is the most difficult target. A higher magnification is OK for a pure silhouette rifle, but is harder than a 6X to hold steadily in a field position when you have been climbing ridges, is less bright on dark days or in heavy foliage, and usually has too small a field of view for tracking a fast-moving bushytail!

For hunting a 2-minute dot at the center of the crosshairs provides a highly visible aiming point, in poor light, but one which does not obscure small game targets at realistic ranges. An additional 1/2 minute dot centered 7" below the crosshairs provides correct 100-yard holdover for standard velocity target, or sub-sonic hollow-point hunting ammunition. Set the second dot at 6" if you favor high speed ammunition. Dick Thomas at Premier reticles can provide this service on most scopes for a reasonable charge, with about 3-6 weeks turnaround time.
(Editor’s Note: Since this article was written, Premier Reticles has stopped offering aftermarket reticle services, having transitioned to manufacturing scopes exclusively a few years ago - see my SHOT show recap for a discussion of their new product line. At this moment the only place I know that can provide an aftermarket reticle such as Ed describes is the T.K. Lee Company in Alabama.)

Many people have wanted the address of Jim Coleman, who built my rifles, I guess because they have seen the copious volumes of accuracy data featured in American Rifleman and the Gun Digest. I am happy to do this, but point out there are plenty of competent gunsmiths who can do this work. I am pleased with what Jim did for me, but I have no financial stake in this whatever.

James C. Coleman can be reached at Coleman's Custom Repair, 4035 North 20th Rd., Arlington, VA 22207, telephone ( 703) 528-4486. It is best to query him by phone first to see what his current work load is, as he is a one-man shop.

Now that you have some ideas on how to make a really serious rimfire, we better warn those bushytails to jump fast and stay hidden!
Comments

The start of a new week.


You may have noticed that there was no Friday Surprise last week. In fact, it wasn't until yesterday that I noticed there was no Friday Surprise! Apparently I simply lost track of what day it was, one of the risks of working by and for oneself.

---

I need your help. I'm looking to scope a few old .22 rifles, and would like to find some vintage scopes to do so. What I'm looking for are the Weaver Model A4 (4x power, 3/4" tube) or the '60s vintage Bushnell Custom jobs with the integral full-length dovetails (also 4x magnification.) Yes, I've tried the usual places (eBay, etc.) and for such a common item they just don't show up very often. They're not exactly high dollar attractions, and I suspect that's the reason no one bothers to list them on the auction sites -- not enough return on investment.

Should you happen to possess one of these, and should its optics be in excellent condition, and should you wish to part with it, drop me an email.

--

Speaking of .22 rifles: there are tons of inexpensive autoloading .22s in the marketplace, and if they're not Ruger 10/22s no one seems to take much notice. I've talked to more than one person who bought a Mossberg or Savage or Marlin .22 auto at a gunshow and sold it off immediately because it "didn't work right." They usually end up going to Wally World (or the local equivalent) and getting a 10/22 on sale, secure in the knowledge that the Ruger will work where those "cheap guns" wouldn't.

I've salvaged several of those gun show rejects, and with only one exception (where I had to replace an extractor) they were returned to proper function simply by cleaning the bolt. A .22 rifle is a dirty beast, and over decades of shooting the extractor and firing pin channels become caked with goo (a technical term used by gunsmiths.) By pulling the bolt from the gun and getting rid of that sandy, greasy mess you can solve 90% of functioning problems.

Cheap .22 rifles are to be celebrated, not feared. They're easy to fix and loads of fun, even if you can't buy carbon fiber geegaws for them.


-=[ Grant ]=-
Comments

Monday meanderings.


Back To Work - Returned last night from a rare (for me) three-day weekend. I spent the time in the eastern half of the state (the desert part) to visit relatives and do some shooting. The last such trip was two years ago, and I'd forgotten what it was like to relax!

Somewhere Steve Wozniak Is Crying - The Firearm Blog brings us news that an Aussie company has developed a sniper moving target system using Segways as drones. I was pretty pumped about that - shooting a Segway would be almost as satisfying as perforating a Prius - but alas the little things are armored. Still, it's a neat concept. (I like the part where the Segways run for their lives at the sound of a gunshot!)

Shooty Goodness - One of the topics of discussion amongst my cousins this weekend was their desire to go to Knob Creek for the annual machine gun shoot. Turns out it was happening literally while we were talking about it, and Tam was there.

Pest Control - The shooting part of my trip involved helping to rid my cousin's ranch of the dreaded sage rat. Sage rat hunting has become a Very Big Thing out here in the West, and despite hundreds of thousands of the things being dispatched every season the population continues to outbreed the hunters. Damage to crops from sage rat infestations is staggering, and it doesn't look like the problem is going to end any time soon.

There are a couple of schools of thought regarding the hunting of sage rats. One school likes to set up a shooting bench and snipe the things from long range with a .22-250. The other prefers to use a .22 rimfire, and just get closer. I belong to the latter group, as using a rimfire is significantly cheaper and still quite challenging. (In a good field it's not unusual to go through 500 rounds a day, and I'm just not wealthy enough to afford to do that with a centerfire rifle!)

Another benefit of using rimfires is that it's easy to get kids involved. It's important that children learn early the necessity of responsible wildlife management. The reason we shoot the sage rat is because a) the population is out of control, and b) poisons aren't an option in areas with large raptor populations. (How many of you have actually seen a bald eagle hunting prey? I saw a half-dozen just this weekend, which is the case every time I go out there. With poison, that wouldn’t be the case.)

Happiness Is A New Gun - My nephew Roman came with us on this trip, and I presented him with his first “grown-up” rifle. Up to this point he'd been using one of the little Chipmunk rifles, and it was time for him to upgrade. I gave him a Glenfield Model 25 with some special touches: I shortened the barrel to a more kid-friendly (yet legal) length, tuned the trigger just a bit to get rid of the horrendous grittiness, floated the barrel, and mounted a 3/4"-tubed scope. It turned out to be a fast handling, accurate little gun which he quickly put to good use, making some excellent shots in very challenging (windy) conditions.

Some Thoughts On Equipment - It's normal to think that a beginner doesn't need top notch gear on which to learn how to shoot. My nephew reinforced my belief in the opposite view: the novice is more in need of quality equipment than the experienced shooter. It's hard to learn all the nuances of good shooting when one is fighting with substandard gear, and good quality guns and ammo don't stand in the way of skill development. Regardless of the age of the student, If one is just starting out it's important to buy the best equipment one can afford. It is only after the basics are mastered is one able to rise above his/her equipment, but poor equipment can keep one from truly mastering even the simplest techniques.

-=[ Grant ]=-
Comments

Still more about testing .22 long rifle ammunition.


A recent email asked about
an old article, wherein I talked about the problems with residual lube in a .22 rimfire barrel. Is it really a problem, the email asked, and if so how do I go about eliminating that variable in testing?

Yes, the effects are real. I never believed in the residual lube theory until I saw the results for myself, and to this day I can repeat them at will with that rifle and ammo.

My test protocol now is to use a standard smallbore target, the type with 6 bullseyes on a sheet. The upper left corner is used to fire 25 seasoning rounds, without regard for group size. This both burns off any residual lubricant and allows me to make any sight adjustments to bring the rounds fairly close to center. I then fire a 5-round group at each remaining bullseye, which gives a good average of the groups that ammunition will deliver. If you're counting, that's one single box of ammunition on one sheet of paper.

Rimfire purists will point out that this is not a sufficient number of rounds to really ascertain the true performance of any specific load, and I'll admit that subsequent testing will sometimes show small differences in group size (better or worse) than this. If you're a serious rimfire match shooter, you'll need to fire hundreds of rounds to truly judge what the ammunition will do. Of course, if you are that person you also won't be looking here for advice!

I've found my test procedure to be the easiest, fastest, most reliable method to obtain a decent (field-grade) indicator of relative performance of rimfire ammunition.

-=[ Grant ]=-
Comments

More on testing .22 Long Rifle ammunition.


As I've mentioned from time to time, shooting .22LR "seriously" can be a frustrating experience. It is almost expected that two identical rifles will have very different ammo preferences - and, unlike centerfire cartridges, the differences are often astounding.

For instance, I have one rifle that shoots it's favorite load into an average 5-shot group of .275" at 25 yards (from prone.) However, that same rifle shooting it's least favorite load struggles to maintain 3" at that same distance! What's more, once you find that one load that shoots well in that one gun, the next batch (lot) of that same ammo may not. It will never be as bad as the best to the worst comparison, but the variance can be enough to put the next best (or sometimes the third best) in the top spot - until you change lots again, of course!

Finding the gun's favorite load is strictly a matter of trial and error. It's not usually even a matter of the type of load; for instance, a gun might shoot one particular 36 grain high velocity hollowpoint load very well, but the next maker's similar fodder won't be even close.

Those who are serious about their rimfires, therefore, tend to do a lot of ammunition testing. When I acquire a new .22, I'll run as many as 20 different kinds of ammo through it, keeping careful notes about the results. This takes time, and if not done correctly results in meaningless data!

As you probably know, .22 ammunition is externally lubricated. That is, each bullet has a coating of some kind of lube to keep it from fouling the bore. Each maker uses a different lube, and sometimes they'll use different lubes within their own product line.

The problem is that residual lube from one load can affect the next few rounds using another load. Case in point: some time back I was testing a new rifle with a couple of different loads. I had just finished with Wolf Match Target, and loaded in some much cheaper Federal stuff. The first 5-shot group with the Federal was absolutely astounding - an honest .175" group at 25 yards! I don't know which amazed me more, the rifle or the ammo, but I wanted to do it again!

I loaded another magazine, "assumed the position", and shot another group. This one was slightly larger, which I attributed to me. I repeated the procedure, and this time the group had almost doubled in size. The next one was even worse.

What accounted for that first group? After thinking about it, and reading some information from Steven Boelter (whose rimfire experience dwarfs mine), I came to the conclusion that perhaps there was some residual lubricant from the Wolf ammunition which was "contaminating" (but in a good way) the Federal load. Testing my hypothesis was easy: I shot a few magazines of Wolf, then switched to the Federal. The first group of Federal was, again, under .200" for 5 shots. The following groups deteriorated rapidly, just as they had the first time. A repetition of the sequence duplicated the results. It seemed that the Wolf lubricant affected the Federal rounds in a good way, but as it was rapidly depleted from the barrel the groups suffered.

From this I adopted the rimfire shooter's testing procedure: when switching loads, first clean the bore (a quick brushing will suffice.) Then, shoot 1 round of the new load for each inch of barrel length to "season" the barrel to the new ammo before firing any groups that will count. This is Boelter's recommendation, and I've found it to be sage advice. Remember: only after the seasoning rounds have been fired do you shoot any for score or analysis.

Those first few rounds may group better, or worse, than the shots following. It doesn't matter, because the groups made after the seasoning process are the ones that tell you what the load really, truly does in that gun.

-=[ Grant ]=-
Comments

In praise of the "boy's rifle"


When I was a kid (which was not all that long ago - at least I don't remember it being all that long ago) we had "boy's rifles." Today they're known by a more politically correct term, but as Juliet said "That which we call a rose, by any other name would smell as sweet."

The boy's rifle was chambered in .22 LR, and was most often a single-shot bolt action - though repeaters were not unheard of. Their wood stocks were sized slightly smaller to fit a teenager's frame (before the days when teenagers were routinely 6' tall and weighed in over 180 lbs), and were slim from butt to forearm. The grip area was smaller in circumference to fit shorter fingers, and the receivers and barrels were similarly proportioned.

Though not normally fitted as nicely as the adult-oriented rifles in their respective lines, they usually shot pretty well. Some, in fact, were downright amazing, especially considering the very simple sights they carried.

People used to larger guns are often astonished when they pick up an old boy's rifle; light weight, quick handling, and superb pointing characteristics are almost foreign concepts today. Unfortunately, those attributes usually lead to snide comments about feeling "like a toy." Were they to actually shoot one - or, better yet, pack one into the field - perhaps their opinions would change. I know mine did!

Like many people, I have a number of "adult" .22 rifles, none of them weighing under 7 lbs. I recently acquired an old Stevens Model 66, which is a bolt action tube fed repeater. At barely 5 lbs, it's definitely a lightweight - but this 70-year-old gun, well worn on the outside but pristine on the inside, is an absolute joy to shoot.

The best word I can use is "handy". It's the kind of gun that carries unobtrusively on the shoulder, yet springs immediately to eye level when needed. It makes my "grown up" .22 rifles seem ungainly by comparison.

Give one a try. You may just get hooked - and wasn't that the whole idea behind the boy's rifle to begin with?

-=[ Grant ]=-
Comments

On scope magnification


Moving back to the farm as I recently did has changed my shooting habits. I'm shooting a larger amount of rimfire rifle lately, not just for fun but also predator/pest control.

For all the years I lived in suburbia (which is a Kafkaesque purgatory for a simple, ignorant country boy like me) I did all of my shooting at the gun club. When I shot rimfire there I invariably took the only scoped .22 rifle in my inventory, forsaking the other iron-sighted rimfires in the safe.

Out here, where the rimfire rifle is a constant companion, the scoped rifle is too awkward to constantly carry around. The open sighted rifles are slimmer, lighter, and less delicate, which means that I'm using them more and more often.

Shooting virtually all open sights has resulted in an interesting revelation: the less magnification I have, the better I shoot.

For years I shot long range rifles with higher magnification scopes. The last centerfire I built - a marvelous 6.5-284 screamer - got topped with a relatively low power 2.5x-10x variable scope, which I've found completely adequate all the way out to 800 yards. Friends shooting at that same range would use 16x or 20x optics, and wondered why I chose the "small" magnification. Even at that time I recognized that the 10x was enough; I just didn't need any more.

As to the rimfires, my scoped rifle carries a straight 4x optic. As I shoot more with iron sights, I find that even this modest magnification is more than I really need, especially from field positions. Even at 4x, movement is sufficiently magnified that my mind starts to play the game that is the bane of precision shooters everywhere: "hurry, the crosshairs are right on target! Pull the trigger now!"

In the field, I've proven to myself that I can shoot open sights more than accurately enough. There are times, though, when a scope would be handy - differentiating target from background in dappled sunlight, for instance. In those cases I'm dreaming of a nice fixed 2.5x scope - or maybe a 2.5x-5x variable, just in case I need a bit more magnification at some point. (In my heart I know that I won't, but the "I might need that someday!" attitude is part and parcel of being an avid shooter!)

For me, less magnification is definitely the way to go.

-=[ Grant ]=-
Comments

On rimfire ammunition and accuracy


Serendipity, that's what it is. Last week a consistent topic kept coming up in a variety of places: the necessity (or lack thereof) for "accurate" .22 long rifle ammunition.

"I don't shoot groups, I hunt {insert favorite furry tidbit here}."
"You can't shoot really accurately in the field anyway, so better ammo isn't worth the price."
"The ammo already shoots better than I can, so I just buy whatever is cheapest."


I believe such comments to be shortsighted. First, though, a bit of information for those not intimately familiar with the vast array of rimfire ammunition.

The .22lr is the most popular (by a huge margin) cartridge in the world. It is available in a bewildering number of forms, from the very cheapest to the "ohmigod, I could buy a good steak dinner for that amount of money!" In general, the more accurate the ammo, the more it will cost.

The odd thing, however, is that not every .22 gun (be it rifle or pistol) will necessarily shoot the most expensive ammo into the smallest group. Rimfires are notoriously finicky; you can, quite literally, take two different .22 rifles, of the same model and vintage (and very close to the same serial number) and each will have very different ammunition preferences. Sometimes the most expensive will in fact shoot the best; other times, a less expensive fodder will do the deed.

In terms of consistency, however, the more costly ammunition will win out - it simply won't vary as much from group to group, even if its absolute accuracy isn't as good. In other words, a cheaper ammo may produce a smaller group occasionally, but the more expensive stuff will shoot the same size group all the time. In the aggregate, the more expensive the ammunition, the more likely it will shoot better in any given gun.

There's no guarantee that you'll set records with more costly bullets, but it's a dead certainty that you won't with WallyWorld specials!

Back to the subject at hand...let's say that you have a rifle that at its absolute best is capable of shooting the magic 1 minute-of-angle (MOA) group (which is, for all intents and purposes, 1/2" at 50 yards.) What this means is that the group it shoots with its best ammunition choice will fit into a circle measuring 1/2" in diameter. Clear so far?

Assuming that the actual center of the group is at the actual point of aim, any shot fired will fall a maximum of 1/4" from the point of aim; this is known as 1/4" radial dispersion. If one shot lands at the extreme edge of that dispersion, and the next at the opposite side of that dispersion, the distance between them will be 1/2", which is the group size. See how that works?

Now, let's say that some other ammunition shoots 4 MOA in this rifle (2" at 50 yards.) Any shot that is fired will now land within 1" of the point of aim. That's still not bad; certainly not enough to even get you in the door at an Olympic training village, but enough to nail pop cans off the fence.

Or is it?

A standard 12oz pop can has a diameter of 2.6", or 1.3" on either side of the center. Aiming dead on that center point, with our 4 MOA ammo, means that the worst shot of the bunch only has .3" to spare to knock the can off the fence. In other words, with that ammo your aim and hold has to vary no more than .3" if you expect to hit the can with any given shot!

Will the better ammo give us an edge? You tell me...with 1 MOA ammunition, the expected radial dispersion is .25". That means that any given shot, holding absolutely dead center, now has a margin of error of 1.05". In other words, your aim and hold now has a bit over an inch of leeway to hit with 100% certainty. I'd say that's a significant advantage, wouldn't you?

Shooting is all about being able to trust your skills, but you can't get to trust your skills until you first can trust your equipment. If you practice by popping cans off the fence, how will you know if that miss was because of your skills, or because of your equipment - and is it the ammo, or the gun?

Someone will no doubt be yelling at his (or her) monitor that not every shot will be at the outer edges of the variables. In other words, an ammo that shoots 4 MOA will distribute shots all over that circle; not all of them will be in the center (otherwise it would shoot better than 4 MOA), but likewise not all of them will fall on the edge of that circle. This is true.

The trouble with this line of thinking is that we don't know where any given upcoming shot will fall. We know that it may hit in the center of its expected circle, or it may hit at the edge, or somewhere in between. We don't know where it will hit until it does; if we expect to hit the target with every shot, we have to assume the worst and prepare for it, looking on anything else as a wonderful happenstance.

It's all about probabilities. Let's take our 4 MOA ammo; it's possible that, say, 80% of its shots might fall within a 2 MOA circle. This means that 80% of the time, you have a bit over 1/2" of leeway on that pop can. Put differently, if you can aim and hold within 1/2" of center, you'll hit the can 80% of the time. If you're happy with 80%, great! (Yes, I'm aware that you can increase the hit probability by simply decreasing the distance to the target. If you're going to shoot everything from 20 feet away, you may feel free to use the worst ammo in the worst gun, and never have the need to improve your skills. Everyone wins - sort of.)

Personally, I'm not enamored with those numbers. Look at it from my perspective: I like to hunt small game with my .22 rifles, both for pest control and dinner. I'm an old farm boy who has a close relationship to the animals around him; if an animal is to die by my hand, I require that death to be as humane - quick and painless - as is possible. For me, that means headshots and instant incapacitation. If you eat small game, you know that head shots are necessary simply to maximize the amount of usable meat from the ammo. Squirrels aren't all that big to begin with!

Further, a missed shot is a lost animal; unlike targets and pop cans, they usually don't wait around for you to try again. I want 100% hit probability if I can supply the necessary foundation (sighting and hold.)

A small animal's head often has a kill zone of around 1-1/2" (even less if forced to take a frontal shot.) If I were to use ammunition that only shoots 4 MOA, that would require me to have absolutely zero error in both sighting and hold to make a clean kill at 50 yards. (Actually, it has negative error - meaning that even with perfect performance on my part, I cannot expect the ammo to deliver a clean hit 100% of the time.) At 25 yards, it doesn't get a lot better - my total allowable aim/hold error for a clean kill is a whopping quarter-inch! Can you do that from a field shooting position? Really? Every time?

Switching to the better ammunition gives me a big edge. At 50 yards my self-induced error allowance is now a half inch, and at 25 yards it is almost 3/4". It means that the chances of a successful clean kill are significantly improved by using the better fodder.

Higher quality .22lr ammunition isn't just for benchresters and group junkies. If one is just starting out, it means faster and surer skill development. For the hunter, it means greater yield and more humane treatment of the animal. In my mind, it's worth the price.

The only thing left is to get a whole bunch of different kinds of ammunition and test them all in your gun. You'll learn just how much you'll have to pay to get the accuracy you really need - not the accuracy someone insists you can settle for!

-=[ Grant ]=-
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