Tag Archives: rifle

Excerpt from “Gunsmithing Student Handbook Series”

At the time of this writing there are three books in the Gunsmithing Student Handbook Series.  In early 2018 “Chambering Rifles for Accuracy” was released.  In its first week on Amazon.com it was #1 in two categories.  Gordy Gritters, famed benchrest gunsmith & Fred Zeglin well known wildcat and hunting rifle maker joined forces to create this comprehensive title.  It covers the subject of installing and chambering barrels from simple rechamber jobs, to hunting rifles and the last half of the book is all about benchrest quality gunsmithing.

The excerpt here gives you an idea of how careful the authors are to cover details often overlooked in such books.  Enjoy:

Tolerance Stacking; 
                Everything You Need to Know About Pilots?

Chamber reamers come with two styles of pilots, solid or removable bushing (the later sometimes called a floating pilot).  One is evil and one is practically perfection.  But which is which?  I can tell you that in renting tools to gunsmiths I have found the industry is split on this question about 50/50.  In other words, about half demand solid pilot reamers exclusively and the other half will not touch those nasty solid pilots with a ten foot pole.

It is clear that there is a trend toward the removable pilot reamers.  This is because barrel makers are not all holding to the same production standards.  Some have the idea that a tighter bore is better, while other makers hold close to the “standard” bore dimensions.  Example, .308 bores are .300” on the bore and .308” on the groove.  Custom barrel makers have tightened the bore to say .298”  This will required a smaller pilot as the standard pilots are normally .299” with tolerances of + 0 to – .0005”. removable pilot reamer 

Removable pilot reamer.

The reason for the tighter bore?  In short, it is believed that it produces better accuracy.  This is only true as compared to a loose bore that is oversized, i.e. a groove on a 30 caliber of .309 or .310 will produce lower pressures and potentially be less accurate because the bullet is not fully engaged until pressure bumps the bullet up to match the bore.

For a pilot to work correctly it should be .001” smaller than the actual bore dimension.  In other words, it needs to be a close slip fit.  If a pilot is too tight it will bind and likely break the reamer, and possibly damage the bore.  If a pilot is too loose it will promote chatter.  It is possible to run the pilot on a removable pilot reamer closer to the bore diameter (.0005” under bore diameter is ideal), but it must still slip easily in and out to avoid damage to the barrel or the tools.

A little history at this point might be interesting:  Red Elliot was and still is legendary with old timer gunsmiths as the absolute best reamer maker of the last century.  Near as I can tell he was the first to offer removable pilots on his reamers.  Why did he do this?  Well, he found that there were enough different barrel makers in his day that the dimensions of the bore diameter (where the pilot rides) varied a fair amount. 

So, this problem of bore dimensions changing a little is nothing new.  What about SAAMI standards you say?  I will address that in just a moment, for now lets talk about how Red Elliot handled bushing pilots.

I have seen several of Red’s reamers with bushing type pilots, what we sometimes call floating pilots today.  Red held very tight tolerances on his bushings so that it required a little pressure to slide them onto the reamer, held in place by a screw mounted in the end of the reamer the bushing would not turn once the screw was tightened.  This is contrary to the bushing pilots we see commonly used today, where the bushing is a slip fit with about .0005” tolerance internally.  This tolerance is added for manufacturing ease. Tolerance stacking is not usually mentioned in conjunction with floating pilot reamers, but we are going to take a closer look at it here.

Another source of tolerance issues is the fact that the pilot receiver on the reamer must be concentric (round), and in line with the reamer.  If either of these conditions is not correct there will be problems with the reamer cutting oversized or out of alignment with the bore.  Admittedly, this is not much of an issue with today’s cnc machines.  So long as the operator does not make an error, and no chips get caught in the set-up.  One other possible source of trouble would be a warped reamer (not common).

Now for SAAMI, their standards are voluntary, so obviously any barrel maker can decide whether or not to hold solid to the standards.  Industry standard is plus or minus a half thousandth (+ or – 0.0005”) on the bore diameter.  The bore diameter is the smallest diameter of the barrel, also referred to by shooters as “across the lands”.  The same tolerance applies to the groove of the barrel.  I will leave the discussion of groove depth as we are talking about bore diameter as it relates to chambering tools, groove depth does not affect these dimensions.

Admittedly barrels considered “match” grade or “air gaged” are supposed to be held to a tolerance of .0003” or less total variance, end to end of the barrel.  This does not indicate the actual bore diameter, we are left to assume that it is the standard diameter for caliber.  In the case of a 30 calibers we would be talking about a .300” bore.  What if the maker decides to simply use a gage that works with the bore diameter they are making, say .2995” and it air gages as above.  You have a match grade barrel but the bore is at the minimum size according to industry standards. 

Are you starting to see how bores can vary and still be within standards?

Of course there are those makers who operate outside the standards and make perfectly good barrels.  The point being; different size pilots will be needed to chamber these barrels as was recognized back in the 1950’s and 60’s by Red Elliot.  It’s pretty obvious by now that removable pilots are necessary tools in dealing with variations in bore dimensions.  It should be clear by now that variations in bore diameter of plus or minus .001” or even more, is not that unusual, even though such dimensions do not follow the voluntary standards set by SAAMI.

Solid pilot reamers offer certain advantages over the floating pilot.  First and most obvious there is no built in tolerance between the bushing and the reamer, because the there is no bushing.fixed pilot

 

 Solid Pilot Reamer

Since most barrel makers today are making barrels by the button rifled method dimensions tend to remain pretty steady for a given maker as buttons last a long time if properly cared for.  So if you deal with the same barrel maker all the time chances are a solid pilot reamer will fit the same from barrel to barrel. 

There are other factors that play into the bore and groove dimensions, but that is for a discussion for another book.

One limitation of a solid pilot reamer is that it cannot be changed to deal with variations in bore diameters.  Of course you can have the pilot ground down if necessary to fit a tight bore, but then you would probably need a second or even a third reamer to deal with various diameter bores. 

Everything in life is a trade-off.  Because of the expense of multiple reamers for the same caliber removable pilots are a cost effective answer to the problem.  $10 for a bushing beats $100 or more for another reamer.  There are shops that stock bushings in 0.0002” steps for the popular calibers.  This allows them to match the bushing to the bore every time.

pilot bushingsPilot bushings can be a big investment.

To make the use of removable pilots efficient and accurate, the gunsmith should invest in a set of pin gauges.  These are precision ground pins that can be used to gauge the bore and insure that the correct bushing is selected.  Using pin gauges allows the gunsmith to know what bore diameter the barrel maker is really supplying.

Now keep in mind the pilot has to slip into the bore, so in mechanical terms the pilot has to be about 0.0004” smaller than the bore to slip in without any interference. In most shops the pilot is figured at 0.001” smaller than the bore and rightly so.  Too tight a fit can gall and or leave marks in the bore or stress the reamer and break it during the reaming process.

What happens if the pilot is too loose?

Ninety-Nine times out of a hundred when a reamer chatters (vibrates) in use, it is because the pilot to bore fit is too loose. 

The lack of support when the pilot is too small allows the reamer to move around in the bore, as the tool tries to bite into the steel it grabs hard and because even tool steel is flexible you get chatter as the tool loads and releases tension.  This is the reason that some gunsmith’s insist on having a set of pilots that cover the possible variations in .0002” (That’s 2/10,000 of an inch.) increments.  Keeping the pilot as close to bore dimensions as possible will help eliminate chatter and promote a more precise chamber. 

If you have a pilot that is a perfect match for the bore but is too loose on the inside where it rides on the reamer then the advantage of a close fitting pilot is negated.  To pull the whole concept together…  If you have a .0002” tolerance on your bushing to barrel fit and the same on the pilot to reamer fit, you end up with .0004” total slop on the pilot. 

I can tell you that most people do not grasp this or understand why these tolerances  matter.  I base that statement on 30 years of talking to gunsmithing customers, and the people who call to rent tools.  The comments that shooters and gunsmiths make during our conversations indicate their level of understanding in a hurry.

In general if the total pilot run-out is under .001” then all will work fine and there should be no worries.  This rule holds true for solid pilot or removable pilot reamers.  Long ago I lost track of how many rechamber and barrel jobs I have done.  I can tell you that

Chambering Rilfes for Accuracy, cover

 it is possible to get an accurate job from either type of reamer.  In fact, if pressed for a choice I would say that solid pilot reamers are more accurate on average.  Especially for inexperienced gunsmiths.

I do not make this statement lightly, as I own hundreds of reamers of both types.  This goes back to the understanding of how the tools relate to the barrel.  To reiterate, the one caveat would be that for best accuracy the pilot of the reamer must meet the tolerances of less than .001” run out verses the bore, for all this to hold true.

There is another major factor in how well a reamer cuts and how accurate the gun will be…  The gunsmith must do a good job on the set up for machining.  If the threads are not true to the bore, or the chamber is crooked or oversized, or the throat of the chamber ends up off center, accuracy will be elusive to say the least.

Use of a floating reamer holder is a great way to insure an accurate chamber.  This tool allows the reamer to follow the hole in the barrel without any side pressure that might be caused by minor misalignment of the tail stock to the bore of the lathe.

Whether you plan to build accurate hunting rifles or top quality competitive benchrest and long range guns this handbook has detail descriptions and plenty of clear photos to make the subject easy to understand.  The other titles in the series deal with headspace, the vital counterpart to chambering, check them out here.  More titles are planned for the series.  These are college level training manuals that a gunsmith at any level of experience will value.

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The Big News for Fred Zeglin, April 2018

How many authors can brag that they held #1 in two categories on Amazon.com?

I don’t know the answer to that, but I am one of them so here I am, bragging.

Last month (April 2018) Gordy Gritters and I (Fred Zeglin) released our new book, “Chambering Rifles for Accuracy”.  This book is the 3rd in the Gunsmithing Student Handbook Series. Obviously the reception of the book and it’s counterparts in the series has been very good.  It’s gratifying to see our work appreciated by so many customers.

On behalf of Gordy and myself.

Thank you for pushing us to #1 on Amazon during the first week of April.

#1 on Amazon

#1 in Two Categories on Amazon!

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Christensen Arms, Modern Precision Rifle

Additional Calibers added to the Modern Precision Rifle™

Gunnison, UT – (January 16, 2018) Building upon the successful launch of the Modern Precision Rifle, Christensen Arms has expanded the caliber offerings for the popular rifle.  Beginning in January 2018, just in time for SHOT Show, the Modern Precision Rifle will be offered in a long-action configuration with .300 Winchester Magnum, .300 Norma Magnum, and .338 Lapua Magnum available. Additionally, Christensen Arms has added the new 6.5 Precision Rifle Cartridge to the short-action lineup.  Also chambered for 6.5 Creedmoor and 308 Winchester.

IMG_9868

The Modern Precision Rifle was developed with a proprietary chassis built with aerospace materials to optimize weight savings (16” .308 weighs under 7lbs).  It also includes an adjustable folding stock with a locking hinge mechanism, an oversized fluted bolt knob, and a black nitride coated bolt, receiver, and muzzle brake.  The Modern Precision Rifle is built with an aerograde carbon fiber barrel, free-floating handguard, and adjustable comb; and is guaranteed to shoot sub MOA.

“…as a benchmark, the MPR is going to be damned hard to top,” said Brian McCombie of American Hunter after his initial review of Christensen Arms’ new rifle.

About Christensen Arms
Founded in Utah in 1995, with roots in the aerospace industry, Christensen Arms developed the first carbon fiber rifle barrel. This patented technology resulted in one of the most innovative advances in firearms within the last two and a half decades. With more than 20 years of firearm experience focusing on incorporating top-tier aerospace materials and processes, Christensen Arms manufactures some of the most lightweight, precise, and accurate firearms in the industry and around the globe.

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224 Valkyrie introduced by Federal Premium

Federal Premium® has announced introduction in time for the 2018 SHOT Show, a new cartridge designed to capture market in the popular MSR (Modern Sporting Rifle; Don’t you hate all these acronyms…) AR-15 platform.    The cartridge is design to capture the hearts of long-range precision shooters. The 224 Valkyrie produces flat trajectories, and  claims match-grade accuracy and supersonic velocities beyond 1,300 yards downrange.

“It beats the ballistics of all other MSR 15 cartridges, including the 22 Nosler, 223 Rem. and 6.5 Grendel. Plus, it offers comparable performance to larger rounds like the 6.5 Creedmoor, with roughly half the felt recoil—and at a more economical price,” explains Mike Holm, Federal Premium Centerfire Ammunition Global Product Lane.  “The 224 Valkyrie is based on a 30 Rem./6.8 SPC case necked down to .224 caliber,”

Shooters can review the technical specifications for the new round once it is approved by the Sporting Arms and Ammunition Manufacturers’ Institute (SAAMI) which is expected in January at the 2018 SHOT Show in Las Vegas. At that time, information such as chamber specifications and cartridge pressure standards, proof pressure range and barrel length/twist recommendations will be communicated. Cartridge and chamber drawings will also be available soon after SAAMI approves the cartridge for standardization.

Testing conducted by Federal Premium engineers using 24-inch test barrels with a 1:7 twist revealed the 224 Valkyrie offers up to 128 inches less drop and 69 inches less wind drift (with a 10 mph crosswind) at 1,000 yards than other MSR 15 rounds. The new cartridge also offers significant advantages in velocity and energy.

Print

Courtesy of Federal Premium®

The 224 Valkyrie will initially be available in four loads: 90-grain Gold Medal Sierra MatchKing, 60-grain Nosler Ballistic Tip Varmint, 90-grain Fusion MSR and 75-grain American Eagle TMJ. These proven Federal Premium bullet offerings provide options for long-range competitors, target shooters and hunters pursuing game from varmints up to deer-sized animals.

Federal created a new 90-grain .224-caliber Fusion bullet specifically designed for hunting deer sized game. In a test barrel the 90-grain Fusion exits the muzzle at 2,570 fps. This is going to be the thumper that P.O. Ackley pushed for 50 years ago. He stated back then that a “bullet of the CORRECT DESIGN AND CONSTRUCTION” was necessary for such cartridges.  Such bullets have not really been available until recent years.

224ValkyrieVs22_250

224 Valkyrie ammo dimensions estimated from reamer print.

Federal Premium engineers designed the 224 Valkyrie for gas-driven MSR 15 actions, bu it’s also extremely effective from bolt guns. “You can also buy a new upper and use it with your existing lower. A gunsmith or other person trained in building MSRs can also make the necessary modifications. The easiest way for shooters to capitalize on the new cartridge is purchase a firearm from one of the many gun makers jumping on the 224 Valkyrie bandwagon,” says Holm.

Reloading data will be available in spring of 2018, when SAAMI releases it’s specifications.  Reloading die sets will be available from RCBS, and other ammo-building components will also be offered by several popular brands.

There are nearly 20 gun makers who have already started producing guns for the 224 Valkrie.  So if your hoping to try one out, it should not be hard to locate a gun in your local store before long.  4D Reamer Rentals LTD has already bought reamers and gauges for this new cartridge, in stock even before SHOT Show.

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Reloading A to Z, from AGI

Guest Blog By Jack Landis

Showing case changes

Explaining how cases are changed when fired.

AGI Tech Services
Manager and Editor, GunTech Magazine

One of the questions I have most often fielded from AGI students and prospective students over the last several years is; “When are you folks going to do a comprehensive reloading course?”

Well, the stars finally aligned and we convinced Fred Zeglin to take the few weeks he had off between the courses he was instructing and his latest writing projects to use his impressive knowledge of reloading and cartridge design to teach this course.

Fred has an extensive background as a professional custom gunsmith, cartridge designer, and author. His books Wildcat Cartridges, Hawk Cartridges, and his AGI instructional video course, Taming the Wildcat are well worth studying by students of the subjects.

This new course is almost eight full hours of the information any reloader needs to know. As he says in the introduction, “There is something for everyone here. If you’ve never handloaded, everything you need to know to assemble safe, effective handloads is here. If you’ve loaded for years, odds are you will still find out things you never knew, considered, or completely understood.” Let’s take a look at what’s actually under the hood . . .

Disk 1 – Brief History of Reloading: This is no exhaustive history of every step in the evolution of loading firearms and cartridges, but rather a concise explanation of how we got to what we actually do today.
Reloading Components: Here Fred shows the various types of cartridge cases, bullets, primers, and powders. He explains their differences and the reasons why those differences exist. Why are spritzer bullets pointed?
Why are some powders shaped like little rods?
Ignition Theory: What happens from the moment the firing pin strikes the primer to the exit of the bullet from the barrel is carefully explained and shown in drawings.
Pressure Curves: A PressureTrace Internal Ballistics System is used to show the real-time gas pressure rise and fall from primer ignition until the bullet leaves the barrel, approximately 1.5 milliseconds. Fred draws curves
which demonstrate what the pressure curves would look like in the Fred Zeglin, Cartridge Designer
case of a dramatic overload, high pressure caused by an over-length case, and powder detonation which can
occur if a very small charge of slow burning powder is used in a large case.
Resource Books: Fred explains why the Cartridge Comparison Guide belongs in your library as well as other books
that give you information on a huge number of cartridge’s dimensions, shapes, ballistics, and terminal performance. The reference books discussed will help you decide what cartridge you might want in your next gun.
Reloading Manuals: Reloading without these “must have” sources is like driving with your eyes shut, a real recipe for disaster. You need more than one so you can cross reference loading data to make sure the load you are
contemplating is safe.

Disk 2 – Developing a load plan: What IS a loading plan and why do you need one? Have you
decided what the load you’re thinking about creating is supposed to accomplish? Do you have a purpose for loading it? What is it? Is it reasonable?

Powder and bullets shown

Selecting correct components for your load plan.

He explains to you why you shouldn’t be “That guy” who just searches for the hottest published load for his cartridge and doesn’t “Waste time” with Starting Loads. “Hey, if it’s published it’s safe, right? These guys always leave a safety
margin, right?” Why you need to keep a complete notebook recording loads, velocity, accuracy, etc.
The Bench: Where should it be, how should it be constructed, how sturdy does it have to be, how high should it be, and why. Press and Die Set-up: Learn how to properly set up the dies, shell holders, and decapping pins from a two die set in your press.

Prepping the Brass: Cleaning, Reaming Inspection: Why you need to clean and inspect your brass, chamfer ream the case mouth and clean out the primer pockets.

PressureTrace Internal Ballistics System
What’s in a “Complete loading kit?” Fred opens a big box from Hornady that contains everything you need to load quality ammo, other than cases, primers, bullets, and powder. Why these make sense for the beginner.

Lubrication: Fred shows you several different methods and products to lubricate the cases prior to resizing, and
why you need to do it.
Full-Length Sizing Dies vs Neck Sizing Dies: Ever wonder what the hoopla about neck sizing from accuracy buffs is all
about? Fred explains why you might want to do it, what makes you able to do it continuously with some cases, why you’ll have to eventually full-length size, and how to avoid “Over-sizing.” Do you know what guns you should not only
never neck-size for, and moreover why you’ll need a “Small base” die? What IS a small base die?
Sizing the Cases: By this time, you will be all set to make those cases like new again.
Priming the Cases: Fred shows you four different priming methods, and why some are better than others in his opinion.
Measuring the powder: Several different scales are shown and how to set them up. After that Fred dips, throws, trickles, weighs, and finally stands and watches a machine do it all.

Disk 3 – Charging Cases: Now we actually begin to load cartridges. Attach the powder measure to the press, verify it is throwing the correct weight, adjust the die so the case is just partially re-sized, and dump the powder into the case. Watch Fred set-up the bullet seating die for no crimp, set the bullet on the top of the case and feed it into the die, adjust its seating depth, and . . . voila!! A real live reloaded round of ammunition made by your very own self.
Seating Bullets with a Crimp: Here you will learn how to set the seating die so it will crimp the case mouth into the bullet’s cannelure just as the bullet reaches the correct depth, and why and when you sometimes need to do this.
Using the Lee Loader: Robart Schaefer demonstrates the use of the basic Lee Loader. Many of we “Senior” reloaders started with one of these tools. It gives you everything you need to load one caliber of good quality ammo for ~ $28. Just supply brass, bullets, primers, and powder. The box holding the tools will fit in the back pocket of your jeans, assuming you don’t fill them as full as some of us.
Fred at the bench demonstrating proper die set up
Next up is Robart Schaefer again, this time with the Lee Hand Press. This is basically a bench type press that
you can use sitting in your La-Z-Boy while watching football. And I have. While it won’t full length resize large
cases, it will do everything else. I probably used it more than anything else with a Lee decapping die, got
my youngest to do a bunch too, and then primed those cases with a Lee Auto Prime. Yep, thousands of them. Got them both for under $50 more than a couple of years ago.
Reloading Cartridges with a Three Die Set-up: Fred explains the use of three die sets. The third die is used to bell the mouth of straight wall cases and pour the powder charge through into the case.
Annealing Brass: Working (sizing) makes it hard and susceptible to cracking. Heating it softens it again and allows more loadings. Fred shows how to do this and gives several alternatives and cautions.
Case Trimming: Here’s where you learn how to trim those over length cases back to the correct size with a couple of different tools and ways of measuring.
Additional Case Prep Procedures: Learn about vibrating, tumbling, and ultra-sonic case cleaners. Learn how and why we uniform primer pockets and flash holes.
Reloading Cartridges Using a Progressive Press: Fred demonstrates a progressive loading press, and describes what happens, and how, at each station.
Disk 4 – Tools and Accessories: Fred wraps up the cartridge reloading portion with a “Show and Tell” of some specialty tools that will make your reloading easier. Shown are extended shell holders to ease the loading of really short cases, a competition shell holder set whose heights vary by .002 inches to allow you to set the exact amount of case sizing you want, powder measure baffle and drop tube, and neck lubers for neck sizing. Specialty dies include neck sizing dies with interchangeable bushings to adjust neck tension, Lee Factory Crimp dies, in-line feeding and micrometer seating
dies, and bullet pulling dies. An impact bullet puller is demonstrated as well.

Bullet Casting: Robart tells us why we should consider casting our own lead bullets and shows what tools and equipment are needed for the process.

Lead: What kinds of lead alloys are needed, where to scrounge what you need, or buy it pure or ready alloyed
if all else fails. The characteristics of the various alloys are discussed and their uses explained.
Pouring Ingots: How and where to heat your lead safely, why and how to flux, and cleaning the dross off the top. It’s kind of cool to see the steel wheel weight clips floating on top of the lead. How to pour the cleaned and alloyed lead into
smaller, easily handled ingots . . . into what looks like corn cob shapes in a jello mold. Why you can never have water around hot lead.
Casting Bullets: Now we get down to actually pouring lead into the molds. How to tell by looking at the bullets whether the lead, mold, or ladle is too hot or cold. He pours from a ladle into the top of single and double molds, and from the bottom into a six bullet mold.
Testing Hardness: Here is a tool the tests the Brinell hardness of the cast bullets and explains how you can determine how hard they have to be based on the chamber pressure of the cartridge they are going to be fired from.
Sizing and Lubing Bullets: Why cast bullets need to be sized and lubed after casting, and how it’s done. What to use for bullet lubes is a choice made based on the bullet’s expected velocity The Lube Sizer Press: This press has a heating
element that heats the lube before it deposits in the lube grooves, seats a gas check, and sizes the bullet, all in one
smooth stroke of the handle.

Final Thoughts on Bullet Casting: Robart wraps up his discussion of bullet casting with a reiteration of why it’s a cool thing to do, and repeats the cautions earlier expressed. Have fun and be safe!

Epilogue: Fred closes by showing a bullet neck concentricity gauge and explains what it tells you and why it is important as a lead-in to a discussion of why learning even more advanced techniques can improve your abilities as a reloader and shooter. If you have never reloaded a single cartridge, you can do so with success and confidence after watching this video course. You will also be able to make informed choices on what tools and equipment will fit your needs and budget.

As a bonus, AGI put Darrel Holland’s Advanced Reloading Techniques course in the package too!

Reprinted courtesy of Hot Brass Magazine

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5.56 x 45 (Nato) vs. 223 Remington; The Ongoing Saga

The subject of 223 Remington vs. 5.56×45 (5.56 Nato) is a popular source of discussion.

Probably one of the best blog posts on this subject can be found at http://www.luckygunner.com/labs/5-56-vs-223/

One item this and most of the discussions seem to overlook is headspace.  Since this blog leans more toward gunsmithing subjects, I wanted make sure this subject was discussed.   I often hear from clients that the 5.56 and the 223 differ in headspace.  The truth is, when I checked the various gauge makers they are all working to the same standard.

Why is this important?

Mainly because educating the shooting public minimizes accidents and makes life easier for all concerned.  None of the articles I looked at mentioned headspace.  Most of the chamber dimensions being shared do not include headspace dimensions.  This may be in part because they are so hard to locate for the 5.56 Nato.

Forster Products publishes the data for their 5.56 gauges.  Minimum headspace (Go gauge) is 1.4636” according to their specifications with a tolerance of -.0003”.  With the Maximum (Field gauge) measuring 1.4736”; that’s 10/1000s of an inch longer than the go gauge.  Most No-go gauges would be set .004” to .006”  longer than the Go gauge.  The Pacific Tool & Gauge print shown here uses a Go gauge that measures 1.4636”.

5.56 Nato Print

Look at the Minimum Headspace dimension listed on this print, it is identical to the dimension used on the 223 Remington.

SAAMI specifications for the 223 Remington show a Minimum headspace (Go gauge) of 1.4636” identical to the military spec for the 5.56×45.  The Nato round is not a SAAMI cartridge, so they do not provide prints or specification for it.

My curiosity as to why so many shooters think there is a difference between the gauges for these two, led me to do an Internet search to see what people are reading.  I consider all material on the Internet to be of dubious quality until I can confirm the data through trustworthy sources.  What I found was interesting; you have to dig deep to find anything that pertains to headspace and the 5.56 Nato.

What is easy to locate are drawings which purport to show why the two cartridges are not the same.  The dimensions  they are concerned with mostly have to do with the junction of the body and shoulder plus the shoulder and neck.  In the real world the camming action of the bolt closing would be more than sufficient to deal with the tiny difference that might exist in the brass.  Frankly there is more variation in tolerances allowed that these drawings account for, in short, it’s all smoke and mirrors.

One Internet source shows the Military gauge .001” longer than is found in the prints mentioned above.  Even if that were the case, that is only 1/5th of the difference between a standard Go and No-go gauge for the 223 Remington.  To be totally clear, it would make NO difference.

Conclusion:  Headspace gauges for the 223 Remington and the 5.56 Nato are identical.  The differences between the cartridges has to do with case wall thickness and how they are loaded.  If you want to shoot either type of ammo in your gun, rechamber it to 223 Wylde.  The Wylde chamber is designed to work safely with both types of ammo.

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New Approach to Firearms Education

Flathead Valley Community College will launch a new two-semester evening Firearms Technologies Certificate starting this fall.  The 27-credit program will feature curriculum developed to support the growing firearms industry in the Flathead Valley in Montana as well as across the country.

One of only a few colleges in the nation to offer firearms related programs. FVCC has taken a unique approach, developing the program as an enhancement to its existing industrial machine technology program introduced last year under the Department of Labor “Amplifying Montana’s Advanced Manufacturing and Innovation Industry” grant (#TC-23760-12-60-A-30).  This approach will make FVCC the only school that focuses on manufacture of firearms and related parts.

The new program will provide students the opportunity to incorporate advanced machining skills with an understanding of firearms operational systems. Courses are tailored to emphasize the manufacturing of firearm components.

Fred Zeglin, curriculum coordinator for the program, developed the courses under the guidance and input from local firearms manufacturers.  “Manufacturers say they are seeking trained machinists who understand firearms.  Classes have been designed to build understanding of a wide variety of firearms and the way that they function.” said Zeglin.

Emphasis will be placed upon the completion of several gunsmithing projects involving blueprints and schematics using a combination of both hand and machine tools. This program will provide a clear understanding of firearms design and function, enabling graduates to assist with design implementation or tolerance issues in manufacturing environments.

The program will be held in the evenings with labs during the daytime on Friday and Saturday. Course topics will include firearms introduction and safety; manual mill and lathe systems; bench metal techniques; firearms theory and firearms repair; machine tools for gunsmiths; and precision rifle building.  This selection of courses are designed to increase the marketable skills of the students in the manufacturing realm.

The program will be marketed nationwide bringing focus to the local industry.  Prospective students must apply both to the program and for admission to FVCC. Program applications are due August 1 at 4 p.m. Applications are available online at http://www.fvcc.edu/firearms or in the Admissions Office in Blake Hall on the FVCC Kalispell campus. For more information, contact Jori Bullemer at 756-3905 or jbullemer@fvcc.edu or Will Richards at 756-4862 or wrichards@fvcc.edu.

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NRA Short Term Gunsmithing Program, Kalispell, MT

FVCC LogoFlathead Valley Community College is hosting the NRA Short Term Gunsmithing Program again this summer.  2014 will be the third year for this program at FVCC, the program has grown in attendance each year and this year should be no different.  New classes are being offered so if you attended or looked at the offerings in the past there is probably something new for you this year.

Quality instruction is the name of the game at FVCC.  The instructors for the Short Term Program are all top notch professionals who are well respected in the gunsmithing community.  For instance, Lee Helgeland is one of the premier stockmakers in the nation.   He has spent 30 years perfecting his craft and is a member of the American Custom Gunmakers Guild.  Another instructor new to the Kalispell program this year, Sam Hatfield, certified NRA and Sig Academy Master Instructor.  Sam was head gunsmith at Green Mountain Guns in Lakewood, Colorado and served as a member of the United States Army Marksmanship Unit as a gunsmith. Sam now owns Hatfields Gunsmithing Inc. in Manassas, VA.

To learn more about the instructors for this summers program check out this link:

http://www.fvcc.edu/continuing-education/gunsmithing-program/instructors.html

New classes this year include “S&W Revolver Action Work”, “1911 Handgun AMU Accuracy Rebuilding” and “Accurate Reloading for the Hunter”.  Perennial favorites like “Customizing AR-15 or AR-10” and “Introduction to Checkering” will still be on the schedule.

If you have ever wanted to learn more about gunsmithing but can’t take of the two years necessary for most schools, the NRA Short Term Gunsmithing Program is a great alternative.  Classes normally run or one week, Monday through Friday.  They are intensive hands on classes with small numbers of students, so you have great access to the instructor. This unique learning opportunity is set up as part of the Continuing Education Department of the College and the courses are non-credit.

If cost is a concern I noticed that the College has some Scholarships provided by NRA donations, details at this link:

http://www.fvcc.edu/continuing-education/gunsmithing-program.html

An electronic copy of the brochure for these classes is available at this link:

http://www.fvcc.edu/wp-content/uploads/2013/03/Gunsmithing-Course-Brochure.pdf?2ebeaa

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How To: Inlet Your Barrel Correctly

A barrel should be inlet up to the center line of the bore, or in other words, half it’s diameter should be below the wood line.  All too many new gunsmiths and hobby gunsmiths just inlet until they can get the screws into the action and call it good.

There is a simple way to make sure your barrel channel is deep enough so that the bore line will be aligned to the top of the stock.  Take a square and place the outside 90 degree corner of the squared into the barrel channel.  If the square touches on all three sides then the barrel channel is a half circle.  GEDSC DIGITAL CAMERA

If the point at the bottom of the barrel channel touches and keeps the sides from contacting the top of the stock then your too shallow.  Conversely, if the point of the square does not touch but both sides are in contact with the top of the stock then your past 50 percent depth.

Fred Zeglin is working on a series of booklets, “Gunsmithing Student Handbook Series”.  This little how-to tip is just one peek into the upcoming books.  What gunsmithing tips would interest you?

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26 Nosler UPDATE, post SHOT Show 2014

Cartridge for 26 Nosler next to similar cartridges

26 Nosler is a new cartridge design, it actually fills a niche in the factory cartridge world.  Between the WSM cartridges and the RUM cartridges, the first being short action, the latter being full length magnum.  So the 26 Nosler is in between.

This may not sound like a big deal but it was a very good idea for a 6.5mm Magnum.  When the 7mm or 300 Remington Ultra Mag is necked to 6.5mm it’s not very satisfactory.  The case capacity is far overbore for the 6.5mm bore, so accuracy suffers and finding a good load is difficult.

By reducing case capacity as Nosler has done with this new design they have brought the balance between bore and capacity back into a range where load development is easier and barrel life will be better than with the full length RUM wildcat such as the 6.5MM UltraCat originated by Z-Hat Custom back in 1999.

26 Nosler drawingDesigned with a maximum cartridge O.A.L. of 3.340”, the 26 Nosler cartridge functions in a standard length magnum action with a 3.400″ magazine box.  It is very similar in length to a 300 Winchester magnum case.  This equates to a shorter bolt through and lighter weight gun than with the full length magnums like the 300 H&H or 7mm RUM.

The 26 Nosler is capable of pushing a 130gr bullet at a Muzzle Velocity of 3400 fps according to Nosler.  With that kind of velocity bullets must be made for the extra stress that velocity will bring to the jacket.  No disrespect to Nosler but this is a job for a NorthFork Bullet if I ever saw one.

The 26 Nosler is a non-belted, 6.5mm centerfire rifle cartridge.  With a useable case capacity of 93 grains of water, the 26 Nosler is speedy, it outperforms the 264 Win Mag by over 200 fps with a 130 gr bullet.  Loaded with the 129gr AccuBond-LR, the 26 Nosler retains as much velocity at 400 yards as the 260 Remington produces at the muzzle.

26 Nosler compared

Zeroed at 350 yards, the 26 Nosler has a maximum point blank range (PBR) of 415 yards.  It appears from the chart at the right that Nosler is figuring 5 inches +or- form zero to get to that 415 yard point blank range.

Nosler’s choice of a 6.5mm cartridge is a good one, sectional density and high ballistic coefficients make 6.5mm a good bet. Retained energy and accuracy at long range is always good with a 6.5mm.  This will be a good cartridge for wide open western hunting for deer class animals.  Thumbs Up!

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