Get to know Jerry Cupples & the Pelletgage!

Michael

Administrator
Staff member
Hey everybody, today we're going gonna have a little Q&A with Jerry Cupples owner/inventor of the Pelletgage.

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Jerry, tell us a bit about yourself like where you live, your career, family, etc.

Hello, Michael and Airgun Nation!

I retired from working as a process engineer and manager in the electronics assembly business in 2016. I lived in the Dallas area for nearly forty years. In 2015 I bought my new home on the Blue Ridge, in the Saluda Mountains near Hendersonville, NC. My grown son Jeff is in Richardson, Texas. I live in the woods, effectively, and there is little limit on shooting around my home.

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So what year did you start Pelletgage?

In spring of 2015.

Let’s assume that our audience has never heard of Pelletgage or even pellet sizing & sorting. Briefly explain why you created the Pelletgage & why it’s important.

My friend Joe Peacock showed me his product called Speedy Pellet Inspector. It was designed to help sort out pellets that have visible defects, and we all know that putting them into a tin and shaking them can cause some damage. If you look close, there can also be malformed pellets. I asked Joe if there was any intent for measurement, and he told me that his CO2 laser did not have the necessary precision to cut plastic for that. In my career, I had long used laser cut steel tooling for circuit board assembly. The idea bulb flashed on over my head, because I knew how to make make (arguably) the most precise laser cuts in the world. About a week later, I had a prototype in my hands, and used an optical comparator to confirm the diameter of the apertures were in 10 microns steps. Ten microns is 0.0004 inches, and the size accuracy of the apertures vs nominal size is less than 0.0001 inches. Some people think they can get the same accuracy with calipers, but I doubt that.

So, I took it home and checked my first two tins of pellets, same well known brand… one was mostly 4.51 mm, the other 4.53. While I could see that the pellets were indeed fitting into the expected apertures, I was very disappointed when checking that first tin, almost every pellet was the same. But I have since seen many big variations within tins that should have the same diameter. I believe that even the best pellets on the market have variation, and sometime that variation produces noticeable effect on shot groups. and I know that some rifled barrels are more sensitive to this than others. My thoughts are that subtle difference in the barrels choke, crown, and the heights of the lands vs the groove are what cause this sensitivity. The fundamental concept is to assure you have consistently sized pellets, and so far, it’s a certainty that they may have adverse variance in lots, and also true that you may get a consistent shift in size from the same nominal diameter products.

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Why did you spell it Pelletgage instead of Pelletgauge?

The term “gage” is well established in technical usage. To gage is basically to use a simple mechanical reference for sizing. Gauges are devices that make a complex measurement for rotation, pressure, velocity, etc. So, in engineering terms, Pelletgage is a “fixed gage”; designed to assess a specific attribute based on comparative gaging and used for quickly assessing approximate size in a go / no-go manner. This isn’t really a misspelling, but I will admit, most spell checkers want that extra “U” I registered the domain names both ways :)

Do you actively shoot airguns? 

Yes, I have a small collection, and my brother (Dr. Tommy Cupples) and I frequently set out spinners or paper targets for friendly contests. Tommy has had airguns a lot longer than I. He gave me my first “adult” gun sixteen years ago, a .22 cal Chinese break barrel from Mike Melick. It was an eye opener for me, it had much better power and accuracy than I imagined. I have quite a few of them now, including some classics like a pretty Sheridan Blue Streak. I also have a couple of nice rifles set up for field target, so I enjoy shooting a wide variety of guns, including some that burn powder. I recently got an older Daisy No. 25 BB gun just like the one my dad gave me in about 1963, and it has been destroying cans out in my back yard…so I sell a BBgage, too!

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What is your favorite type of airgunning? Benchrest, FT, Hunting, Plinking…

Field target. I have competed for about six years. I met a number of good friends in the Texas FT clubs, and have enjoyed the (usually) good natured sport. It’s effectively a bunch of grown kids playing with toys in some ways, and we share the fun of getting accuracy in different trajectories, target distances, and weather conditions. North Carolina has a lot of FT shooters, and I have enjoyed meeting some great people here. It’s typical to find that airgun shooters have much in common, and can share those interests in enjoyable ways. In Dallas, we had the “North Texas Airgun Militia”, a silly name for a group of people who’d gather a couple of times a year and shoot thousands of pellets from dozens of guns at various targets. That was one of the reasons I got into airguns.

What do you enjoy doing outside of airgunning?

I like to hike in DuPont State Forest very near my home, and ride my Polaris UTV on the roads and trails nearby. My property adjoins Jones Gap State Park (in South Carolina), there are thousands of acres of scenic public lands and waterfalls near me, and I see a beautiful sunrise off my deck most mornings. I collect flashlights and pocketknives, and tinker around with those, too. I tune in to many types of radio to get weather and news, and try to keep a cellular data connection alive far from a tower.

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Which do you feel is more important: weighing your pellets or sizing them?

Pellet weight is secondary to the diameter, likely because manufacturers have better process control for that variable. Airguns have some interesting dynamics, and my brother compares the firing cycle to that of a blowgun. The fit of the pellet OD to the gun barrel as it travels the rifling lands and again at the crown are a big part of what guns “like” a particular pellet. If your blowgun is shooting darts that don’t fit well, it affects the consistency for velocity, and the consistency of the exit from the crown.

I know from experience that sizing & sorting does make a difference & I was able to prove this out at EBR this year.

I’m glad Pelletgage helped you, and I have had many similar responses. A number of people have said they were rescued from total frustration after various gun tuning, barrel cleaning, scope changing, etc. when they found an issue with the pellets they had always used successfully in their favorite rifle. Benchrest shooters are good customers, along with field target competitors. Airgun hunting is becoming more popular, too. Hunters are very serious about making clean shots after all the effort needed to track game. They want accuracy when they pull a trigger in that big moment.

Even with the best quality pellets, the risk of having that one undersized head that costs a point in competition is avoidable. I believe many shooters are not aware of the pellet head diameter that their gun works best with. Most guns can do reasonably well with a range of head sizes, but there is still some improvement to be had. For instance, pellets mixed with 4.51/4.52/4.53 will all do pretty well, but the resulting group size of the mixed pellets is larger than the group sizes achievable when only the 4.53 was being shot. It’s then a matter of ‘how small do you need that group to be?’. Competitive shooters not only want to eliminate “fliers”, they want to hit that small kill zone out there at 40 yards, repetitively.

Are there any “famous” shooters that also use the Pelletgage?

Michael Wendt! ;-) I can look at the winners lists from field target and benchrest competitions, and see quite a number of Pelletgage customers, including European contests. Before the 2016 Olympics, I had a coach for the US team contact me with interest, and I donated a number of Pelletgages for use at the US team training facility in Colorado, and they did OK! Let’s see…Tom Gaylord (BB Pelletier) has written about it, and one of my first customers was Stephen Archer. Pelletgage is used to find head diameter sizes for the pellet reviews done for Stephen’s Hard Air Magazine.

You recently released the PelletgageR. How is it different than the original Pelletgage & how do you use it?

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PelletgageR is designed to efficiently sort pellets for a specific, narrow size range. There are 48 apertures in the gage plates, all the same diameter. By using two gage plate (a “go” and a “no-go”) the user can quickly sort for the size desired. Pelletgage can be used to sort pellets, but only one at a time. Pelletgager is at least 10 or 20 times faster. PelletgageR can be used with two gage plates stacked and registered, so that when the pellet drops into the top plate, it can either catch on the larger aperture (oversized) catch on the lower aperture (desired size) or drop through the lower aperture (undersized).

Who would you recommend use the Pelletgage products?

Any “serious” airgun shooter. There have been quite a few sold to airgun dealers and people who write about the hobby. I don’t think purely casual shooters need this, and it won’t make a $100 gun group like an FX. I once shot a FT match with a very serious and well equipped shooter. We were squadded together, and he commented while shooting that he was surprised that people would pay $49 for this tool. I commented back to the guy (as he took aim with his Whiscombe rifle with March scope) that it surprised me that some people would invest so much money in airguns and not make every effort to get the best possible pellet. He said “you have a point” :).

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Right on Jerry, Thanks for spending a few minutes with us. 

If ya'll have any questions for Jerry or want to share your experience with his products... please chime in!


 
Very nice interview guys! Thanks Jerry for what you have shared with the community in the development of the pelletgage. I have one in .25 and have found some very eye opening facts about different pellets and different guns that are fussy and some that are not. Your contribution to the sport is very much appreciated. Thank you.

PS Wife and I spent about a year in Greenville SC and hiked the Jones Gap State Park several times. Very beautiful part of the country, but wouldn't want everyone to know that, so your secret is safe with us. lol.
 
Great interview Michael . I've been lucky and got to spend some time with Jerry . What a great guy and a real gentleman.

It's super easy to talk over my head as any one who has met me can testify to . But when I met Jerry for the first time and he explained how the pelletgage not only worked , but the level of precision it takes to make it I was impressed for sure ! 

I own a .177 and .22 and they are really cool . When pressed for time I use mine as kind of a go-no go guage which help me sort out the really outta round pellets ya sometimes get . It's a really useful tool in a lot of ways . 
 
Jerry is a great guy. I was very lucky to get to know Jerry shooting FT here in Texas. When I announced I was going to start hosting FT matches at my range 5 years ago, Jerry Couples and a few other veteran FT guys, contacted me and came out to meet me. Jerry pretty much came to every match I held until he retired and moved to NC. I miss not seeing my friend at our monthly Texas matches.

When Jerry was in TX he developed the PelletGauge. There was a lot of time & money spent getting the PelletGauge to the end product. Jerry kind of made it sound simple in his interview but he went thru multiple processes/methods to get the holes precise. Jerry isn't in the garage doing this with a drill press. First he had to find vendors to precisely make the holes and then find vendors to inspect them for precision, etc. There was a process there to find the right combo of methods, materials, & testing to get it right. So when I saw all he went thru I felt the price for the gauge was a bargain when I bought mine. It's a handy tool. It is an eye opener sizing pellets. Do not believe the head size you ordered is what you got. Sometimes you wonder why they even put a head size label on the tin at all. Another part of the interview Jerry mentioned Joe Peacock and the Speedy Pellet Inspector. Joe is another great guy and the Speedy Pellet Inspector works great. Kind of cool these two guys that came out and shot my matches, saw a need, and did the Texas thing by saying screw it. I will build it.
 
Hello, JoeWayne, Craig, Bill, Don and all,

Thanks for the kind words. 

The issue we all face is whether the pellets are consistent. There are apparently some obscure reasons why any given pellet will not perform. If you scour the net, you see discussions about how a particular lot is great/terrible and that there are mysterious reasons apart from pellet head size. I have seen clear evidence and reports examining the back of the pellet, revealing that the punch used to push the slug into the swage die can differ. This can be seen as a smaller/larger recess. This is sometimes mixed in one tin, and is rather obvious when you know what to look for.

This type of inconsistency could simply affect the way a given gun's bolt pushes the pellet into the leade during loading, but also may affect the balance of the pellets mass, and the rotational inertia of the pellet - thus its ballistics. I've always felt that any imperfection that affects how well the pellet spins (think of a top that is not concentric in weight) would immediately affect accuracy.

I think we'd all like to solve the mystery of why pellet variations - even in the same brand and caliber - seem to have magical effect on accuracy. I feel sure that the head size- and the consistency of the head size - is one factor. From many reports, the effect of this variance is much greater for some rifles.

All of this goes back to what the manufacturer is doing within the tooling, processing, and I believe, in the inspection and sorting that they do (or don't do) that results in lot-to-lot changes.

Incidentally, FunGun,the waterfall shown in the post is Falls Creek Falls https://discoversouthcarolina.com/products/25555 and that creek begins a 1/4 mile from my home. The falls is about a mile down the hill from me. Watch for bears up here. The photo shows one of four visitors to my deck this year.

Merry Christmas to all my airgun friends!
 
Nice interview. Congratulations on the PgR’s launch, Jerry!

The German roll out gage is interesting. Converting € to $, surprising that the price point I’d just under $200, although I suppose there are still shipping charges to consider. Looks like it can measure concentricity and roll out of the head/skirt, and the recess in the back side of the pellet. The poor man’s run out gage for the pellet exterior is rolling the pellet in a glass surface to see if it wobbles. The recess under the skirt was an eye opener to me some years ago when I got my first multi-shot CO2 air rifle that loaded with bolt action from a rotary magazine. Accuracy was lousy until it was pointed out to me that the air rifle ineeded pellets with a tight fit of the probe at the end of the bolt to the hole under the pellet skirt to load consistently. Compre, for example, JSB exact to RWS Superdome, Both very good pellets, but look up the skirt and one can instantly see a big difference.

The ‘pop gun / blow gun analogy comes from the now out-of-print “The Airgun, fromTrigger toTarget” , Cardew & Cardew.

Springers are like pop guns — designed to have a tight fit of the pellet at the breech. The piston compression causes a very rapid increase in pressure (and temperature) at he skirt end of the pellet, which tends to form and seal the skirt to the bore at the breech. The pellet only begins to move when the pressure behind the pellet passes the threshold when, like a child’s pop gun, the pellet pops loose and begins to accelerate down the barrel. Inconsistent head size and dinged skirts both affect the consistency of the timing of the ‘pop’ of the pellet, and, therefore, the pressure behind the pellet as the instant it begins it’s accelleration down the bore as well as the resistance to pellet movwmwnt down the bore.

Old BB guns are more like blow guns. In some cases, the BB can even roll out the end of the barrel if it is tipped downward. The projectile is like a loose fitting feathered dart. In blow guns, the pressure accelerating the projectile is much less dependent on the fit of the projectile.

Modern PCPs (I suspect, but don’t know for sure) may somewhere in between — seemingly not as tight as the fit of a pellet in any of my springers, but certainly not as loose as the BB guns I grew up with. Must confess that I have no real “feel” for pellet fit in my PCPs that load with a bolt rather than a fingertip mechanically seating the pellet. The only single pump pneumatic airguns I own that load with a fingertip rather than a bolt are my “Izzy” IZH-M46 target pistol, and Walter LGR-U 10-meter air rifle. Both prefer a relatively loose fitting pellet, but the fit is still much too snug to be consider either “blow guns”.

From reloading brass for powder burners, I know 2 things for certain. First thing: the distance from the bullet surface that engages the lands and grooves to the point beyond the breech chamber where the rifling begins, the “jump”, is critical, for two reasons. 1) seating bullet depth in the brass so that when the cartridge is loaded, the bullet is already touching the lands, tends to better center the bullet in the bore, and 2) seating the bullet in the brass so that the bullet is touching or even ‘jammed’ into the lands causes a significant (and potentially dangerous) rapid increase rise of chamber pressure that builds in after the powder is burning, but before the bullet begins to move down the bore. Second thing: concentricity of the brass holding the bullet to the centerline of the bore is critical. Any run out of the bullet relative to the brass case and neck means the butlet is off center and canted as it is entering the rifle bore. Independent of the powder load, both seating depth (pressure variations) and concentricity (centering in the bore) affect accuracy. That’s why custom bench rest rifles have very high tolerance chamber size, and often, reloading dies made with the same machine tooling at the same time, and with identical precision to the custom barrel chamber. Mass produced rifle barrels and rifle ammunition have much lower, looser tolerances, so that one standard fits all.

The parallels to airgun accuracy, head size (pressure variation) and concentricity (bolt probe to pellet skirt recess fit and centering with bore on loading) appear to be similar in importance for best accuracy. Air gunners don’t have custom barrel chambering, and few if any “reload’, but it is possible, now more than ever, to custom fit mass produced pellets to your favorite airguns. If you shoot at competition levels, especially bench rest, then a few millimeters may be critical. But if you just like to plink or target shoot off hand, then minute of accuracy in the range of the head size of a small rodent is all you really need . . . except for those pesky flyers! And still, there are those gearhead geeks among us who enjoy having and playing with airguns, pellets and the tech tools that go with, just because we can.
 
Welcome Sir!,

I see the need for your product, although I've also been looking to get sizes made for my better airguns that are finicky.

I very well may try your product & I'm happy to see you enjoy a beautiful country setting life. 

An example Where I could use your .177 gage. My 1991 RWS 48 is incredible. I think I can get it to be just as good further out if I found 10.5's that weren't so dang tight. Crosman magnums would be good candidates for an actual sizer in this case. Any plans on doing anything like that in future? 

If anyone reading this wants 3 tins of undersized .177's, give me a holler. They must have been made for a very small ".177" barrel.

Welcome Sir & thank you for your invention.


 
I became an 'early adopter' of Jerry's PelletGage in 2016 when I purchased a .177 gage. It has served me well and is still a 'go-to' tool when I'm going to shoot FT.

I've added several airgun rifles to my modest collection and they are in .22cal running PCP. I just recently contacted Jerry for a .22 Pelletgage. I have received a most courteous and personal reply from this fine gentleman on New Year's (today!!!) I was wonderfully surprised to receive his response and grateful for getting such a prompt acknowledgement and assurance that the .22cal I purchased would be sent to me. Thanks again Jerry for the incentive.

Reading this article has permitted me to know better this ingenious individual and appreciate the priviledge of having dealt with him in a personal fashion. 

Cheers!