Author’s Note:  This writer is a reporter, pure and simple (minded).   I am no physicist, engineer, metallurgist or scientific type of any sort.   Any similarity between the content of this article and scientific accuracy   must be attributed to the work of others more qualified.  Hopefully, however, some of their findings, valid or invalid,  are accurately reflected herein. That said, settle back and, hopefully, you, too, will enjoy an enlightening  chuckle or two. That is the intent.

            It was five o’clock in the morning.  Still dark outside.  The  dog and I had been outside so she could do her early morning “thing.”  Second cup of coffee was just above this keyboard on the computer desk.  I had dealt with  my e-mails and turned to Benchrest Central’s Rimfire Forum to see what thread of interest someone may have posted overnight.    There it was: “Pecking & tapping my way to a tuned rifle?” by a guy whose moniker (User Name) was Colt .45. 

Ole Colt .45 had written, “Well, I bought a stethoscope, I read everything written here recently and I have pecked, tapped and thumped until I’m blue in the face…I’m not sure I have a clue what I’m hearing or not hearing?  I removed my Hoehn tuner and Henrich  mid barrel.  I put my stethoscope against the side of the stock, the side of the forend, the bottom of the forend and just behind the tang.  It seemed like I heard most clearly with it behind the tang.  I tapped with my index finger, it seemed like the sounds I heard were a kinda bonggg with an echo like until one point about 6” from the muzzle.  Then it was just bong,  no echo?”
            By now this reporter, having experienced many times the frustration inherent in tuning a rimfire rifle,  was laughing uncontrollably, enough to start the dog barking and my   spilling  coffee all over  the desk top.  Colt .45 continued, “Forward of that (bong)  the echo was back.  I put the Hoehn back on without the weight or bloop tube and the bong without the echo was now about 3” from the muzzle.  I put the Henrich  back on and it did not seem to move the bong or dead spot but did make it harder to hear.  I added the 8 oz weight to the Hoehn and it seemed like the bong-no-echo was nearly at the muzzle.  I then added the bloop tube and it seemed like it was at the muzzle?  I never did hear an actual dead spot…thud…just the echo would seem to disappear from the bong sound.   I tried several settings (of the tuner) from all the way in and out to 500.  Was I hearing what I should have or just wasting my time?  I need some input from the tuning guru’s.   Colt (tapped out) .45.”   Colt .45 is  Sergeant Alan Fisher, a 25-year veteran of the Missouri Department of Corrections who is into his second year of rimfire benchrest competition.

            Thus began a search for bong, bongggg and a thud.     Responses to Colt .45’s post came from across the country and around the world.   It was to attract five pages of questions, comments, and suggestions and some 11,000-plus viewers  before it went into the archives.   This reporter’s  belly laughs  began to diminish  as more  bong experiences were reported on the Forum.  Still,  cynicism  prevailed;  all those reported experiences were pretty much discounted  until Allan Hall called and said, “Let me  tell you something…there is something to this bong, bongggging stuff and you need to write about it.”    Allan was reminded this old boy is   already so deaf he  can  no longer hardly hear a 105mm howitzer fire (the source of the deafness); how in blazes would he  know a bong from a bongggg or a thud?   Allan  was told    he needed to  bong a couple of my rifles.   Convince  me.  This was a turn-around for Allan.  His skepticism  about this stuff   dominated  until he sat down with four or five good shooters at the new Kettlefoot Range and those guys “explained” it in such a way that he became convinced.  He said they took  four rifles that were producing exceptional scores up there and “bonged” ‘em with a wood pencil.  Every one of those rifles  had the dead spot (or, thud or bong- with- no- echo) right at the muzzle.  Further, he said, you sure couldn’t argue with their obvious success.  Those guys were so  persuasive   he became a “believer.”     Maybe this writer’s cynicism wavered a bit – but not much.  

            Incidentally, for some reason Colt .45 adds a quote to all his posts on the Forum,  “It’s not much of a crime, whacking a surly bartender,”…Gus from Lonesome Dove.    

A few days later, using a  fifteen dollar Wal-Mart stethoscope, Allan tapped along the barrel of my  Messer-built Hall rifle with a piece of wood doweling.    He found the “thud”  about an inch behind the muzzle and suggested taking the Fudd tuner off.  NO WAY!  It had taken forever to get that rifle tuned and anyone caught  monkeying with that tuner would   face a certain slow  and painful death.    Not ready to die for such a puny cause he relented and began tapping on a Suhl on  which K. C. Young had  installed a heavy Lilja 1:16 tight  bore barrel.    It was  wearing a Harrell tuner which was threaded for additional weights.  He tapped along the barrel until he determined the “thud” was occurring about three inches behind the muzzle.  Putting a three-ounce weight on the tuner moved the dead spot about an inch further forward.   Not much more could be done to that rifle until Lynwood Harrell could ship a set of weights.     They were ordered.   More on this later.

In the meantime, dialogue on the Rimfire Forum ran rampant.     A fellow named Mel Eck wrote, “It works.  We had the opportunity to watch Bill B., now known as head pecker at work , do two rifles in two minutes with awesome results with a turkey call.”

            Sober advice to Colt was offered by Joe  Friedrich, a top notch rimfire  shooter from  Oxnard, California.   Joe wrote, “Colt, with both tuners off you will hear a dead zone; this zone could be ¾  of an inch to an inch long.  The barrel will start to ring (bonggg, whatever it sounds like to one’s self) again past this dead zone.   We all know there is more than one node in a barrel;  many do not agree with this method and it is nothing new but has been successful for us.

            “Colt, you are hearing it right…it is a flat sound like a thud.  I have seen the dead zone with most barrels that are five to six inches behind the crown.  Try the stethoscope
on your scope rings.  The barrel will have the same sound when going past the spot as it did before  you arrived at that spot.”  Another writer suggested ,  “Try connecting the stethoscope with a large paper clip to the trigger guard.”

            Colt replied, “…I’m not hearing the thud that I thought I would hear when I got the node or dead spot.  Instead, I hear a bongggg except at one place I hear the same bong- without- the -echo.  I assume this is the dead spot.  Was that a bong or a bonggg?  It’s driving me crazy!”

This whole  tapping, pecking, bonging process  probably stemmed from   an article by Bill Calfee in the March 2005 issue of PS.  One contributor to this thread suggested  that probability and observed, “Target shooting isn’t a matter of life or death – it’s more important than that.”

            If you read that article you will recall several  points Bill made.  He wrote that after 15 years of  testing barrels in every conceivable way  he had concluded:  the vibrations of a rifle barrel, when fired, are vertical;  the vibrations  (described as a “full cycle”) converge to produce one  node (thud, bong- with- no- echo, per Colt.45); that  node must  be at the muzzle for maximum accuracy; the node pattern is parallel to the bore; and beyond the node vibration again occurs in what Bill described as a “part cycle.”    Bill maintains it is the “part cycle” beyond the node which ruins accuracy.  (There are those who challenge some  of Bill’s observations; we report, you decide.)

            Summed up:  The objective is to use a tuner, weights, or whatever to “fool the barrel” in such a way as to place the node at the muzzle.   This is what Colt. 45 was attempting to do by tapping his barrel and listening to the bong or  bongggg while trying to find the thud (bong- with- no -echo).   Assuming he did, in fact, find it three inches from the muzzle he was using his tuner, additional tuner weights and Henrich device to move the node   (bong-with-no-echo) to the muzzle.   Colt .45 was to report later that he may have finally achieved that goal.  When this was written  Colt had produced one ARA score of 2325 using SK Standard Plus ammo and had placed 7th, 6th and 3rd with two high targets.  “The tuning thing about drove me nuts.  I think my wife enjoyed watching me crawl along the floor with a stethoscope in my ears tapping on my barrel while muttering to myself,” he said, adding, “I tapped with a variety of objects until I discovered my finger worked best – and  yes, I felt like a doofus.”

Regardless of the science, it is generally agreed that best accuracy is obtained when the node (dead spot, bong-with-no-echo)  is at the muzzle.  Adding weight to the tuner can move  the node toward the muzzle.    The additional weight is usually composed of  the machined and threaded weights which screw in to the tuner.   Others report successfully using other methods – one of the most popular being the adhesive backed lead weights used in balancing tires.

            Joe Friedrich said, “I like using the wheel weights because you can stick them anywhere you want on the tuner and placement of the weight is most important.  I have different screw on weights from two to eight ounce increments but will always use the wheel weights which I can place closer to the crown.  I get the best results when I get  just enough weight forward and then the rest close to the crown.”   Joe must know what he’s doing; he has two perfect certified 2500 ARA targets to his credit so far.

            Shucks, armed with all of the information reported above it would appear that getting that node to the muzzle  for maximum accuracy is a lead pipe cinch, wouldn’t it? That Hall/Messer rifle referenced earlier in this article  seemed a natural;  the “thud” had been located only one inch behind the muzzle.  So, adhesive backed wheel weights were added until the “thud” was at the muzzle.  Nothing to it!

But something wasn’t right.  The next morning during practice time preceding an RBA  match this new set up was put into play with ammo that rifle has been digesting  most happily.   Results were disastrous!  A few groups fired into sighters prompted the quick removal of those weights before competition began.  They’re still gone.

            On the other hand, the weight set arrived from Lynwood Harrell’s place for the Suhl with the heavy Lilja barrel.   The mid weight was screwed onto the tuner and several  test groups were fired with  the rifle.   Maybe there was some slight improvement; the node had been moved closer to the muzzle, according to the stethoscope.  That mid-weight was removed and replaced with an 8-ounce screw on weight.  That change produced an eye popping six-round group which measured .072.   Adding more weight caused  subsequent groups   to open up.  Why?  Dunno.  It just did.

No question but what the tapping, pecking, bonging that had Colt .45 so frustrated is being successfully  applied to their respective rifles by some very fine and  well-known rimfire benchrest  shooters.  The results speak for themselves.   Wilbur Harris owner and webmaster of Benchrest Central which provides the Forum, always quick to cut  directly to the point with a humorous comment,  responded to Colt. 45’s plea for help, advising, “…”I’m not even a novice, much less a guru…but what you really want to hear is the Rangemaster saying, ‘and first place with a score of XXXX is Colt .45.”