Determining Pellet ...
 

Determining Pellet Head Size...  

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airmojo
(@airmojo)
Joined: 1 year ago
Posts: 188
2019-11-09 16:21:37  

I recently installed an Air Rifle Headquarters (James Maccari) Pro-Mac Kit in my FWB-124 and did some testing shooting with Crosman Premier Lites (7.9 gr) pellets that I had handy (Die #4 1999)... I got pretty consistent results on my Beta Chrony, but would get a shot or two almost 100 fps less then the other normal consistent shots every so often... and the low velocity shot was noticeably harsher...  I thought maybe I screwed something up, like the piston seal when I installed it, so I disassembled it, expected everything, and all looked good.

Thanks to JM, he said that I the first thing I should try is a different tin of pellets, as the ones I was shooting may have different head sizes and weights... so I did, trying a tin of Beeman Crow Magnums (8.8 gr) pellets, and they all shot pretty consistent with no low velocity shots... I smiled, because it was the stupid pellets not my limited airgun-smithing skills !

So I got out my old BIC pen tube that has a tapered inner tube (clear plastic) that was recommended for checking .177 pellet head sizes many years ago (these pens were hard to find back then since BIC changed this style pen and the inner tube was no longer tapered)... and discovered many variances in the size of the CPL pellet sizes... this is a pretty quick tool to check pellet head sizes, but you don't know the actual size unless you use calipers, and I'm not that anal to sit and do all that.

But was still curious as to whether there was an easy and quick tool to use to determine the head size.

Discovered the Pellegage tool online that has various head sizes to measure the pellet head by finding the correct size by dropping the pellet through it... still kind of tedious, but then I thought that it would be a great way to calibrate the BIC pen by marking the head size on it.

Heck even better would be a manufactured one that has a clear tapered tube already marked with the various sizes, and in different gauges for .177, .20, .22, and .25 calibers... if the tube was long enough it could do all the calibers... maybe there is one ?

Think I will get the Pelletgage tool to try it out, and calibrate my BIC pen tube !

Anyone else remember trying to find the clear tube BIC pen to check pellet head sizes ?

Here is a photo of some of the variances that I found in the CPL pellets that I was using to test my FWB-124... the red tape was kind of arbitrary from what I remember... accepting the ones on or above the red line, and reject the others for plinking tasks.

CPL Pellet Head Measures All

 

Ken H in OH -- Life is One Hole After Another...


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Tom Holland
(@xbowairsniper1200)
Joined: 2 years ago
Posts: 46
2019-11-09 17:45:24  

Airmojo,

I have also discovered through Mr. Jerry Cupples, who makes the Pelletgage,  also makes a head size sorter.

Once you use the original Pelletgage that has the various size holes for .177, the holes range from 4.47 mm to 4.56 mm, to sort a decent amount initially.   Once you test all the different head sizes, and you find the best performing head size.  For my uses, this happens to be 4.51mm. 

Jerry was kind enough to send me a Pelletgage R, which is different from the original Pelletgage.   The holes on the 2 metal plates , are 4.52 for the top plate, and 4.51 for the bottom.   All you do is dump a bunch of pellets in, and shake it around.  All pellets that stay proud,  are too big.  The ones that have the skirt sticking up, are the ones that are 4.51, and the ones that dissapear completely,  are too small.  You can sort an entire tin for headsize in about 10 minutes,  it's easy to use, and fast and efficient.   I'll post a review on my Channel below.

 

Tom Holland 

Field Target Tech


 

My Youtube Channel


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airmojo
(@airmojo)
Joined: 1 year ago
Posts: 188
2019-11-09 19:31:48  

Yeah, I saw that one and thought it would be great once you found the right size you were looking for.

I will probably try one, once I try the original Pelletgage one... and figure things out for my various rifles.

But just from my BIC pen sorting, there are obvious many different head sizes, and I have no idea what tolerances I should be looking for... part of the fun of airguns I know.

I try not to be so tedious in my pellet selection, because I do not shoot at airgun matches, or field target... pretty much just a back yard and basement shooter... but like being able to check the results of a new kit or piston seal installation.

I would rather scratch my butt with a strand of rusty barbwire fence than tediously weigh and sort pellets... but I know it may have to be done like my recent past experience ... 😀 

Ken H in OH -- Life is One Hole After Another...


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nervoustrigger
(@nervoustrigger)
Joined: 2 years ago
Posts: 201
2019-11-10 03:37:00  

With the BIC tube, are you collapsing the skirts?  Pellet skirts are larger than the heads by quite a bit (typ. 0.005" / 0.12mm or so in the small bore calibers) so I'm curious if this method is instead characterizing differences in the skirts.


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airmojo
(@airmojo)
Joined: 1 year ago
Posts: 188
2019-11-10 04:35:36  

@nervoustrigger

No, you just insert a pellet head first into the tapered tube... the skirts do not collapse or change shape.

I've only used it for the Crosman Premier Light 7.9 gr pellets... it may not work for all domed pellets, depending on the length of the pellet and the size of the skirts, so that's a good point to consider.

Ken H in OH -- Life is One Hole After Another...


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James Perotti
(@jpsaxnc)
Joined: 2 years ago
Posts: 77
2019-11-10 09:31:24  

The occasional peewee pellets are a mystery to me. They look fully formed, but I don't understand how they can be formed in the same mold/jigs as the full size pellets.


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airmojo
(@airmojo)
Joined: 1 year ago
Posts: 188
2019-11-11 07:52:53  

Well the problem could actually be the skirt size, not just the head size... but at least the skirt size can be adjusted wider with a pellet seating tool before putting the pellet in the breech...

A die of some sort would be needed to make the skirt size smaller... but don't know why you want a smaller size skirt... I guess it may depend on the gun... I'll have to do some more testing.

Ken H in OH -- Life is One Hole After Another...


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MDriskill
(@mdriskill)
Joined: 2 years ago
Posts: 140
2019-11-12 05:01:55  
Posted by: @airmojo

Well the problem could actually be the skirt size, not just the head size... but at least the skirt size can be adjusted wider with a pellet seating tool before putting the pellet in the breech...

I could be off here, because I’m basing these comments on some older pellets, but I’ve never had much luck with CP’s. The issue is that the head is actually bigger than most other .177 pellets, and the skirts smaller. 

So...they feel tight when you load them, but actually seal rather poorly at the skirt, and that fat head has to deal with the muzzle choke. All in all the perfect formula for inconsistent speeds over a chrono.


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airmojo
(@airmojo)
Joined: 1 year ago
Posts: 188
2019-11-12 12:43:09  

@mdriskill

Hi Mike... Could very well be... I really only use my chronograph when I suspect a possible problem, or install a new kit or seal.

I have several boxes of the CP light 7.9 gr .177 pellets in my stash and used many over the years... although I have not bought any recently due to the inventory I have... and my age ! 😀 Most recent is a Die #1 from 2008.... also have Die #5 1998, #4 2000, #7 2004, #7 2006.

I do recall people complaining about various die numbers several years ago, and I might have a few boxes of those dies.

I did open a can of JSB Exact Diablos that I bought several years ago, but never tried them... I think they are 8.44 gr according to my scale... they seem to be shooting really consistent with the couple of 10 shot strings that I just did.

I'm going to buy some more of those... looks like they may come in two different head sizes... mine does not have the head size marked on the can, but I will check the size when I get my Pelletgage.

I'm a plinker for the most part, but do like to shoot targets to check group sizes at various distances.

I guess I really just need a good reputable pellet for doing any actual testing and chronographing.

 

Ken H in OH -- Life is One Hole After Another...


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nervoustrigger
(@nervoustrigger)
Joined: 2 years ago
Posts: 201
2019-11-12 13:36:46  
Posted by: @mdriskill

I could be off here, because I’m basing these comments on some older pellets, but I’ve never had much luck with CP’s. The issue is that the head is actually bigger than most other .177 pellets, and the skirts smaller. 

FWIW, I have not had much luck with CP's either, at least not since around 2013.  Quality seems to have nosedived since then, even with the previously well-regarded single-die boxed pellets.   From my measurements, the heads are indeed sometimes oversized a bit and usually it coincides with pronounced parting lines, suggesting they were from a die that is being used past its useful life and has worn to the point it is producing a larger head diameter.  However I have not have not observed undersized skirts.  I just double checked some from a tin and some from a box and they fall in the range of 0.182" - 0.185" which is plenty large.


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MDriskill
(@mdriskill)
Joined: 2 years ago
Posts: 140
2019-11-13 05:22:24  

@nervoustrigger

Very interesting!

Again, my comments are based on some pretty old CP’s. IIRC, on those both the head and the skirt measured around .180. Most other pellets in my stash measure around .177 at the head, and .182 and up at the skirt. So as I mentioned the CP’s feel deceptively snug when loading, but I wondered how well they sealed. 


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Hector J Medina G
(@hector-j-medina-g)
Member of Trade
Joined: 2 years ago
Posts: 337
2019-11-13 14:59:09  

Premiers were designed with a different philosophy in mind as almost all other pellets.

Premiers (as well as "Sniper" pellets), seal at the head and the skirt just rides on the lands' tops.

Almost every other pellets is designed so that the head rides on the lands' tops and the sealing is done by the skirt.

If you have the time read this:

https://www.ctcustomairguns.com/hectors-airgun-blog/at-the-moment-of-firing-and-fit-of-pellet-to-the-rifling  

Keep well and shoot straight!

 

 

 

 

 

HM


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nervoustrigger
(@nervoustrigger)
Joined: 2 years ago
Posts: 201
2019-11-13 16:12:05  

Hi Hector, that is an interesting point about the Crosman Premiers. I will say I have noticed that the heads measure ever so slightly larger on average than most other brands (save for the large-binned H&N FTTs and such) but I had never heard or read that they are meant to seal at the head.

So I’m trying to make sense of how this works. Your article says “the obturation (seal) is done at the head, and the skirt is just along for the ride”. I presume you don’t literally mean the head expands and forms a seal at the time of firing, rather just that the head is responsible for sealing in its pre-fired form. In other words, deliberately large enough that it helps seal straight away.

If you do mean the head expands at firing, how is that achieved at any pressure that would not first expand the skirt and seal there?


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TomR_here
(@tomr_here)
Joined: 2 years ago
Posts: 99
2019-11-13 17:22:16  

Interesting read there Hector.  


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airmojo
(@airmojo)
Joined: 1 year ago
Posts: 188
2019-11-14 05:55:27  

@hector-j-medina-g

That's good to know... something that I may have forgotten over the years about the Crosman Premier Pellets... and explains why the old tapered BIC pen tube worked for checking the head sizes of .177 CP pellets without interference of the skirt end of the pellet.

Thank you for posting that !

Ken H in OH -- Life is One Hole After Another...


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Hector J Medina G
(@hector-j-medina-g)
Member of Trade
Joined: 2 years ago
Posts: 337
2019-11-14 08:29:30  
Posted by: @nervoustrigger

Hi Hector, that is an interesting point about the Crosman Premiers. I will say I have noticed that the heads measure ever so slightly larger on average than most other brands (save for the large-binned H&N FTTs and such) but I had never heard or read that they are meant to seal at the head.

So I’m trying to make sense of how this works. Your article says “the obturation (seal) is done at the head, and the skirt is just along for the ride”. I presume you don’t literally mean the head expands and forms a seal at the time of firing, rather just that the head is responsible for sealing in its pre-fired form. In other words, deliberately large enough that it helps seal straight away.

If you do mean the head expands at firing, how is that achieved at any pressure that would not first expand the skirt and seal there?

You are right NT. And BTWm "obturation" just means sealing. Perhaps you are confusing the term with "upset" that is the mechanism where a lead bullet expands inside the barrel when it is fired. The lead bullet will obturate via upsetting. A pellet cannot do that.

Premier's heads are, usually 0.002" to 0.003" larger than the usual pellet, sometimes more. Skirts are relatively slim. If you carefully cut the head off a Premier and pass it through the unchoked portion of your barrel (retrieve it going backwards), you will be suprised.

Also, do note the thickness of the skirt in a Premier.  It is VERY thick when compared to the tail end of a JSB for example.

And last, the skirt is VERY shallow.

It all stems from the way Crosman guns have been designed for MANY years: Usually a bolt action with either a hollow bolt, or a probe (sometime people convert one to the other and make ridiculous claims of improvement, but the improvement comes from the DEPTH of seating that is possible with a probe, and not so easy to achieve with a hollow bolt. Still, the hollow bolt is MUCH MORE REPEATABLE in the seating process and therefore has a much bigger accuracy/precision potential.

Anyway, since the pellet is being mechanically pushed by the user into the rifling, the WORK of engraving the pellet into the rifling is done by the user, not by the spring nor by the compressed gas behind the pellet, therefore it usually is an efficient method.

When using Premiers in spring-piston airguns, my research tells me that the "chamber" needs to be eased a little with a well made cone, smooth and mark-free. And the fit is critical because if the pellet enters too easily, then the piston cannot achieve proper pressure, and if it does not enter enough, then a whole lot of energy goes into engraving the hard head of the pellet into the rifling.

VERY delicate balance.

Hope this clarifies the point.

Thanks for reading!

 

 

 

 

 

HM

 

 


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nervoustrigger
(@nervoustrigger)
Joined: 2 years ago
Posts: 201
2019-11-14 10:13:33  

Hi Hector, thanks for that detailed reply. Yes I was treating obturate as the process for expanding the pellet. I try to be very clear with my terminology so thanks for pointing that out.

You’ve really got me curious about the dimensions. I’ve measured and logged probably a couple dozen tins and boxes since ~2012 and have never seen any heads that measured 0.002” to 0.003” larger than other brands. To be clear, I have found a few outliers that measure 0.179” – 0.180” but not as a nominal across a larger population. Most have hung pretty close to 0.1770”- 0.1775 if memory serves me correctly. For comparison, JSB and AA typically run 0.176” – 0.177”. I may still have some on the shelf from the 2012 – 2013 time frame so I’ll look this evening. That would be the oldest I have though.

FWIW, most times when I’m prepping a new barrel, I will push through a sample of a Crosman, a JSB, and an H&N dome and inspect the engraving under magnification. Indeed, the Crosmans typically show deeper engraving on the head but also on the skirt, or at least a very comparable amount. I haven’t recorded skirt sizes this whole time but as I mentioned in a previous post, I’m getting 0.182” – 0.185” on samples from recent production. I assumed the engraving was from the harder alloy and the thicker, shorter skirt resisting it from collapsing as readily as the other two brands.

Granted I realize that does not take into account what happens when the pressure pulse hits them, but at the same time it points to the Crosman skirt sealing at least as well as the head even if it does not expand. I can see where very tall lands would collapse the skirt in such a way that leaves teeny triangular gaps at the inside corners of the rifling, and those gaps would at least partially close when the pressure pulse hits it. Whereas with chicken scratch rifling, the skirt would seal quite well from the start.

With that said, I’m thinking about capturing some. Do you prefer the pillow stuffing or the water approach? Or something else?


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Skip in WV
(@skip-in-wv)
Joined: 2 years ago
Posts: 76
2019-11-14 15:53:53  

I had one of these pens. It worked well. Dont know what happened to it. Wish I still had it.


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airmojo
(@airmojo)
Joined: 1 year ago
Posts: 188
2019-11-14 19:59:28  

@skip-in-wv

I still look for them at antique shops, flea markets... force of habit due to looking for one years ago !

But only have the one.

Ken H in OH -- Life is One Hole After Another...


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nervoustrigger
(@nervoustrigger)
Joined: 2 years ago
Posts: 201
2019-11-15 00:26:03  

Earlier today I mentioned I would check this evening to see what older Crosman pellets I have from the 2012-2013 time frame (when I got into airgunning).  Turns out I had 4 partial tins/boxes from 2013 so I sampled the skirts of 10 from each and added them to my table of head sizes.  

The first line in the table is some boxed lites purchased fairly recently that I included for comparison.  The other four are from 2013.

Firstly, note the "Head dia / typ" column.  The largest of these were 0.1785" (4.53mm) and the smallest 0.1770" (4.495mm).  Roughly a thou larger on average than other brands I've measured over the years but not two or three.

Next, note the skirts in the right hand column.  Pretty much all run 0.181" - 0.184".  Large enough that a subtly tapered tube would be sorting them by the skirts rather than the heads.  And large enough that I would expect them to form a pretty good seal with the bore.  

For reference, LW specs 0.176" lands and 0.182" grooves, suggesting the heads would form a poor seal relative to the skirts.  Other barrels may differ of course.

I have no idea why these data do not square with Hector's, with one possible exception.  The last one in the list, the batch with largest heads...those are far and away the best Crosman pellets I've ever had.   They are what prompted me to buy the boxed version later that same year (die J shown in the table).  Unfortunately those were pretty disappointing.


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airmojo
(@airmojo)
Joined: 1 year ago
Posts: 188
2019-11-15 05:42:16  

@nervoustrigger

What "tool" are you using for measuring pellets ?

I tried using digital calipers but my wife could not take all my screams of frustration, so I stopped.

I'm expecting the arrival of the Pelletgage that I ordered today... should work out much better ! 😀 

Ken H in OH -- Life is One Hole After Another...


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Gratewhitehuntr
(@gratewhitehuntr)
Joined: 2 years ago
Posts: 390
2019-11-15 07:39:47  

A digital 0"-1" micrometer would be vastly superior to calipers,or to rephrase, calipers would suck for this job.

There are at least 2 meanings for "digital" in regards to micrometers. The 1st sort uses small batteries, total no-go at my house. Period. No. No. No!

Try these, no batteries, NO RECOMMENDATION ON A BRAND OR MODEL,  and you'll still need to read tenths (0.000?) manually.

My personal preference is for mics with a anti-overtightening  spring-clicky-tension-metering device on the tail, even more important with soft parts

(or if you care about accuracy, or newb)

To repeat, these don't use batteries, flips numbers like an old-timey alarm clock.

Once you get a set, you'll suffer the distinct dissatisfaction of finding the heads sufficiently OUT OF ROUND (WTF?) to ruin all your measuring. Basically... yeah.

https://images-na.ssl-images-amazon.com/images/I/41eOvNnhO8L.jpg

There you have it, the world according to John.


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airmojo
(@airmojo)
Joined: 1 year ago
Posts: 188
2019-11-15 08:59:45  

@gratewhitehuntr

Thanks !

I hear you on the battery tools... seems like they are always dead or almost dead when I go to use them.

Forgot I had a micrometer... of course it has a battery... dead of course !

That Mitutoyo one that you show looks more useful... I like no batteries !

Ken H in OH -- Life is One Hole After Another...


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nervoustrigger
(@nervoustrigger)
Joined: 2 years ago
Posts: 201
2019-11-15 10:31:04  

@airmojo, the measurements are made with a set of well-tuned dial calipers that I periodically check/calibrate against precision gauge pins.  The dial allows me to reasonably interpolate to a half-thousandth (0.0005”) and its feedback gives me confidence and repeatability that I don’t get with digital calipers.  True, I can’t get the resolution possible with a good micrometer but that wasn’t my primary goal when I started logging this information a few years ago. It was to check how consistent pellets are within a particular tin. For that, my interest was more about repeatability of measurements than the absolute accuracy of the reading. Accuracy is still important which is why I validate against the precision gauge pins, just not the primary goal. And given the degree of manufacturing variance we see with pellets, a half-thousandth of resolution is plenty to distinguish those with good consistency from those with poor consistency.

With calipers, technique and focus are definitely necessary for repeatability and to avoid compressing the pellet. So in that sense I agree with gratewhite’s comments. It’s tedious for sure. For example, out-of-round heads are common especially with the cheaper brands so I’ll take multiple measurements per pellet when I see that, and I have to take care to avoid measuring across the mold parting lines so that doesn’t adversely influence the numbers.


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Gratewhitehuntr
(@gratewhitehuntr)
Joined: 2 years ago
Posts: 390
2019-11-15 11:01:05  
Posted by: @nervoustrigger

 given the degree of manufacturing variance we see with pellets, a half-thousandth of resolution is plenty to distinguish those with good consistency from those with poor consistency.

Agreed.

 

So there you go Airmojo, gage pins.

If you only need one, I'd be happy to buy the rest, long as price reflected that it was an incomplete set 😉

Get some gage blocks while you're are it, I̶ ̶d̶o̶n̶'̶t̶ ̶c̶a̶r̶e̶ it doesn't matter which grade.

 

Here is another thought for you... depending on ambient temps, your hand might warm a set of calipers enough to change readings.

You probably need to keep the caliper in a baggie in your pocket until warm, then recalibrate on the pin...

Wait... a room kept at 97 degrees... yeah... it's a deep rabbit hole, if you want it to be.

 

"Friction" is the word for that style of mic, not clicky.

 

There you have it, the world according to John.


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Hector J Medina G
(@hector-j-medina-g)
Member of Trade
Joined: 2 years ago
Posts: 337
2019-11-15 13:36:28  
Posted by: @nervoustrigger

Hi Hector, thanks for that detailed reply. Yes I was treating obturate as the process for expanding the pellet. I try to be very clear with my terminology so thanks for pointing that out.

You’ve really got me curious about the dimensions. I’ve measured and logged probably a couple dozen tins and boxes since ~2012 and have never seen any heads that measured 0.002” to 0.003” larger than other brands. To be clear, I have found a few outliers that measure 0.179” – 0.180” but not as a nominal across a larger population. Most have hung pretty close to 0.1770”- 0.1775 if memory serves me correctly. For comparison, JSB and AA typically run 0.176” – 0.177”. I may still have some on the shelf from the 2012 – 2013 time frame so I’ll look this evening. That would be the oldest I have though.

FWIW, most times when I’m prepping a new barrel, I will push through a sample of a Crosman, a JSB, and an H&N dome and inspect the engraving under magnification. Indeed, the Crosmans typically show deeper engraving on the head but also on the skirt, or at least a very comparable amount. I haven’t recorded skirt sizes this whole time but as I mentioned in a previous post, I’m getting 0.182” – 0.185” on samples from recent production. I assumed the engraving was from the harder alloy and the thicker, shorter skirt resisting it from collapsing as readily as the other two brands.

Granted I realize that does not take into account what happens when the pressure pulse hits them, but at the same time it points to the Crosman skirt sealing at least as well as the head even if it does not expand. I can see where very tall lands would collapse the skirt in such a way that leaves teeny triangular gaps at the inside corners of the rifling, and those gaps would at least partially close when the pressure pulse hits it. Whereas with chicken scratch rifling, the skirt would seal quite well from the start.

With that said, I’m thinking about capturing some. Do you prefer the pillow stuffing or the water approach? Or something else?

Water is too hard.

I ALWAYS use pillow Dacron loosely, VERY loosely, packed into a cardboard tube. Been using that same method for nearly 20 years.

That is how the pellets shown as "deformation upon firing" in the blog were captured. It is tiresome because you have to recover every pellet before shooting another, but it is the best working method I have found. Those measurements tell you that the waist increase in the CP's is by far the most significant. Skirts don't get blown out badly, thought they do deform a bit.

I don't know if we are talking about the same thing. When you run the pellets in the barrels, do you push them all the way through? If so, you are getting imprints from the choke, not the main part of the barrel that is responsible for aligning the pellet correctly from the beginning.

IMHE accuracy and precision are dictated more by the fit between pellet and rifling in the MAIN section of the barrel than at the choke.

Keep us posted!

 

 

 

 

 

HM


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Hector J Medina G
(@hector-j-medina-g)
Member of Trade
Joined: 2 years ago
Posts: 337
2019-11-15 14:12:51  
Posted by: @nervoustrigger

Earlier today I mentioned I would check this evening to see what older Crosman pellets I have from the 2012-2013 time frame (when I got into airgunning).  Turns out I had 4 partial tins/boxes from 2013 so I sampled the skirts of 10 from each and added them to my table of head sizes.  

The first line in the table is some boxed lites purchased fairly recently that I included for comparison.  The other four are from 2013.

Firstly, note the "Head dia / typ" column.  The largest of these were 0.1785" (4.53mm) and the smallest 0.1770" (4.495mm).  Roughly a thou larger on average than other brands I've measured over the years but not two or three.

Next, note the skirts in the right hand column.  Pretty much all run 0.181" - 0.184".  Large enough that a subtly tapered tube would be sorting them by the skirts rather than the heads.  And large enough that I would expect them to form a pretty good seal with the bore.  

For reference, LW specs 0.176" lands and 0.182" grooves, suggesting the heads would form a poor seal relative to the skirts.  Other barrels may differ of course.

I have no idea why these data do not square with Hector's, with one possible exception.  The last one in the list, the batch with largest heads...those are far and away the best Crosman pellets I've ever had.   They are what prompted me to buy the boxed version later that same year (die J shown in the table).  Unfortunately those were pretty disappointing.

NT.- I would not worry that our data does not match. After all, I am a dinosaur, LOL!; in the sense that I am referring back to the ORIGINAL design and intent when the Premier was first launched, sometime around the middle 1990's.

My Love affair with Crosman Premiers started in 1997, when I first got back into "Adult Airguns" (with a DIANA 52).  I quickly gravitated to the 0.20" cal for a number of reasons, all of them related to ballistics (internal, external and terminal).

It ended in 2003 when they decided to discontinue the 0.20" cal Premier for the first time (they discontinued the pellet TWICE). By then, the changeover from Pickett to D'Arcy in 2000 had initiated the decline of quality and the decision to drive the pellet making machine to crap.

So, my ideas and numbers come from way back when the Premiers were originally designed, and marketed, and occupied the topmost positions in the competition world (outside Olympics).

Even the Brits recognized the Premier as THE best pellet around.

I will not repeat what DT Fletcher wrote in his book about the "75 years of Crosman Airguns", but I am sure that the CURRENT productions of Premiers have "forgotten" where they came from, the place they occupied, and the respect they commanded.

I fully stand corrected by your measurements and from now on I will be very specific as to the time frame of the CP's when I talk details about them.

Great info!, THANKS for sharing!

 

 

 

 

 

HM


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Hector J Medina G
(@hector-j-medina-g)
Member of Trade
Joined: 2 years ago
Posts: 337
2019-11-15 14:30:07  
Posted by: @airmojo

@nervoustrigger

What "tool" are you using for measuring pellets ?

I tried using digital calipers but my wife could not take all my screams of frustration, so I stopped.

I'm expecting the arrival of the Pelletgage that I ordered today... should work out much better ! 😀 

AM.-

The out of round head shape is a real problem, when I do use the pellet gauge (and I do think it is an excellent tool), I make small washers that pull the skirt plate away from the head measuring plate just enough to align the pellet between two points of support: head plate and skirt plate. 

In that way, you just have to drop the pellet and if it does not go through the head is too big in at least ONE direction. If the pellets are really consistent and uniform and completely round, you will find that all pellets align well and drop where they are supposed to and not drop where they are not supposed to.

If you have the time, read this:

https://www.ctcustomairguns.com/hectors-airgun-blog/the-durango-kid-is-coming-to-town  

Hope you enjoy.

Keep well and shoot straight!

 

 

HM


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Gratewhitehuntr
(@gratewhitehuntr)
Joined: 2 years ago
Posts: 390
2019-11-15 14:39:00  

Seems like less trouble to swage them all the same.

Reloaders do it, remind me what the fault is when applied to airgun projectiles?

edit to remove powderburner content

There you have it, the world according to John.


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nervoustrigger
(@nervoustrigger)
Joined: 2 years ago
Posts: 201
2019-11-16 10:25:17  

Hi Hector, thanks for the tip on Dacron in a tube. I'll see if I can work up something. Not sure if I can get to it this weekend but I'll definitely report back when I do.

Regarding the engraving on heads and skirts from a push-through, I was limiting my comment to unchoked barrels only.

And thanks so much for the history of Crosman pellets. I've been a voracious reader since getting into the hobby but had never heard about their pellets from that era nor the apparent change in head & skirt geometry that distinguishes them from those manufactured these days. See, my narrower time frame was telling me a marked decline had started around 2013-2014, so to think there was time when they were even better than those I got back in 2012-2013 is very interesting...if also simultaneously quite disappointing.

So apparently Crosman has both the knowledge and the ability to manufacture great pellets. They just lack the motivation. Perhaps they would say the market dictates what they do today, I don't know. But with JSB's running about 50% more expensive in .177, it seems like there's a good market segment for them to put out a quality line and continue making the lowball stuff for the Walmart shelves. Sure would be nice to have a legit quality "Made in the USA" pellet.


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