Is it JSB or Me?

[uncle paulie]

A few months ago I ordered 10 tins of .177 JSB Exact Heavies from PA. All of the tins arrived in pristine condition as we have come to expect from PA. Since cracking the lot open, I have been chasing the cause of an inordinate amount of fliers for a couple of months now. I have checked and rechecked the pellet speed, cleaned the barrel a ridiculous amount of times considering I lube my pellets, carefully checked my crown and even swapped out my scope. Recently I decided to get deeper into the situation and bought a jewelers scale to check the weight variation of the pellets. Of the four unopened tins I have left, I found the weights were consistently off; all tins ranged from 10.28 to 10.42 with most of the pellets weighing in the area of 10.32-10.38. I separated these pellets and ran them over the crony. As my standard deviation is around 6fps, I didn't feel this was enough to give me the accuracy issues I was experiencing. As a last Hail Mary, I invested in a $40 caliper and believe I may have come across the culprit. Absolutely none of the pellets measure 4.52. The head size of the pellets of the pellets range from 4.41 to 4.48(10 pellet sample from each of the four tins.) At first I thought the caliper I had just purchased was bogus, but after rechecking the accuracy of the unit against a number of known standards I have come to the unhappy realization that the pellets themselves that are the issue. 

At this point I'm wondering if any others have found similar issues with these and whether or not you have checked yours for head size?

pv

[robertr]

 It is JSB, I had the exact same problem with the AA 16's which are made by JSB. The first batch I bought was accurate, no problems, I then bought five more tins, and noticed accuracy problems and a lot of flyer's.
  When I checked the head size like you did they measured out at 5.48mm or so when they are supposed to be 5.52mm.
 Kind of scared to order more unless the head size is verified.

[nced]

A few months ago I ordered 10 tins of .177 JSB Exact Heavies from PA. All of the tins arrived in pristine condition as we have come to expect from PA. Since cracking the lot open, I have been chasing the cause of an inordinate amount of fliers for a couple of months now. I have checked and rechecked the pellet speed, cleaned the barrel a ridiculous amount of times considering I lube my pellets, carefully checked my crown and even swapped out my scope. Recently I decided to get deeper into the situation and bought a jewelers scale to check the weight variation of the pellets. Of the four unopened tins I have left, I found the weights were consistently off; all tins ranged from 10.28 to 10.42 with most of the pellets weighing in the area of 10.32-10.38. I separated these pellets and ran them over the crony. As my standard deviation is around 6fps, I didn't feel this was enough to give me the accuracy issues I was experiencing. As a last Hail Mary, I invested in a $40 caliper and believe I may have come across the culprit. Absolutely none of the pellets measure 4.52. The head size of the pellets of the pellets range from 4.41 to 4.48(10 pellet sample from each of the four tins.) At first I thought the caliper I had just purchased was bogus, but after rechecking the accuracy of the unit against a number of known standards I have come to the unhappy realization that the pellets themselves that are the issue. 

At this point I'm wondering if any others have found similar issues with these and whether or not you have checked yours for head size?

pv

When I dabbled with supposedly 4.52mm JSB Exacts I had exactly the same issue so I measured a few thousand and this was the result..........


I do have to mention however that I don't put much faith in the accuracy of that "second metric decimal" due to the caliper "unit round off". Here is the digital caliper I use and it's advertised specs..........

The "resolution and accuracy" is listed as 0.01mm / .0005 with the same repeatability.

I've found that pellets CAN be oval by a couple 1/100th of a mm and I also found that it takes a bit of "technique" to get a "repeatable read".
1st.......check the caliper readout with my micrometer test bar always measuring at the same position on the anvils.........


2nd.....I do this.........


As a side note, I recently received 4 tins of 4.52mm Air Arms domes and found that most measured 4.51mm on my EAGems. To verify my caliper readout I sized the head of a few using my home made pellet head sizer that gives me 4.50mm pellet heads. To my surprise ALL the AA 4.52 pellet heads were sized by the sizing ring. I tried to size supposedly 4.52mm JSB Exact pellet heads with my sizer and a HIGH percentage were too small to be sized.

Anywhoo, I found that the 8.4 grain 4.52mm Air Arms domes were a lot more consistent than the 8.4 grain "4.52mm" JSB Exacts and they fit the leade of my HW95 much more consistently.......

[Motorhead]

Yes !!  getting to be more common as JSB has ramped up production in recent years.

Now i have no real experience is pellet manufacturing, but do know as a die wear it does so INCREASING the size of the pellet over the dies life.  it would a somewhat WAG likely not far from reality that NEW DIES are the culprit producing under size pellets.

[uncle paulie]

Well, looks like I'm in good company. Went ahead and pre-ordered some 4.53 Exacts(8.4's) from PA. Hoping these will be sizable to something my HW100 likes; knowing I'll be giving up some weight to combat the wind. I'll post my findings when they come in a couple of weeks.

pv

[robertr]

 Problem is with quality control, that's it.

[whitefox545]

Been saying this for a couple years now,  Used to shoot Heavies but went to the redesigned Monsters two years ago because of head size not being what was marked on the tin!!  Tried buying batches from all over the states from six different vendors, Sorted out 20,000 pellets with .452 marked on the tins and ended up with less than 400 that were .452 about 500 that were .451 and the rest were .450 and .449  with a few even smaller,  Not very good!!  I gave up and went with the redesigned Monsters and never looked back!!  Out of a tin of 400 I may find 10 to 15 that are .451 and the rest are all as marked .452.  Don't know why they bother putting the size on the tin if they don't have any better control than they do!!  VERY Poor Quality control as I see it!!  Good luck!!  I gave up!!  J.L.

[Bryan Heimann]

I wonder if it might also have something to do with speed of production and whatever kind of release agent or lube they are using if any, taking up space inside the die. A miscroscopoc film of- I don't know, Something!- inside the die that is literally a split hair thicker or thinner, more inconsistent, that is impossible to get it just right and keep up with demand for their best sellers

[cootertwo]

The way I measure pellets, is after zeroing my caliper, I open the jaws slightly, and lay the pellet on it's side. Then slowly open the jaws until the pellet falls through. The head is usually the largest part of the pellet. The skirt will fall through first, leaving the head pivoting in the jaws, then just slightly open the jaws till the pellet falls through. This doesn't take into effect that they may be out of round, but I think it's easy to go through a batch this way.

[uncle paulie]

I find the JSB's skirt sizes to be larger than the head sizes, not sure about any of the other brands.

It would seem there's an opportunity for one of the pellet manufacturers to produce a pellet which would be consistently 5.53 to 5.54 in a couple of weights that are designed to be resized by the user.  Considering the cost of premium pellets today, I don't think I would mind paying a couple of dollars more for a tin if they solved this issue.  This would also take the pressure off their QC Dept. to produce a more consistent pellet across their entire line-up. I haven't tried the JSB "premium" pellets. If anyone has any specs on these, please chime in.

pv

[Yogi]

Without a pellet gage I do not know.   All my caliper readings says ridiculously low numbers.  I assumed it is because I am squeezing the soft lead.

-Y

[Tonykarter]

Agreed.  Have a PelletGage.  My 5.52's are all over the place with many as small as 5.48, 5.49, most being 5.50, 5.51.  I bought four tins of 5.54's and many, no, most were 5.52 and 5.53. 

[stevemag]

Hey Paulie!! I just started a thread about weighing pellets because I had a tin of jsb 15.89 that was all over the place , weights from 15-16.5 grains. I started to weigh and sort them and decided to open another tin and found no issues in that one.
I didn’t check head sizes. Figured a got a bad batch.

[uncle paulie]

Hey Steve, that's how I got started in this quest, too many fliers so I started to weigh them. Wasn't just one tin unfortunately. After grouping for weight, still had fliers. At this point, I really think the problem is the head sizes. Might try the monsters, if not, going  to try different brands.

pv

[uglymike]

My last JSB purchase was about year ago, bought a dozen tins of those high $$ 7.87gr. .177s. Seem to be a uniform fit in the several rifles I shoot them in. I don't weight, size, clean, lube, nada, just look at the skirt before I stuff it in and let 'er rip. I'm justa plinker, competitive shooters, I completely understand. 

[Bayman]

I mostly shoot JSB 7.87 and 8.44 Exacts I find the fit pretty consistent. Consistently loose so they probably are undersized. They barely stay in the breech of any of my HWs. That said they still shoot pretty well and at least they don't fall out causing dry fires like the wally world Crossman 7.9 hp. My last vacation I had 2 dry fires from them falling out that broke the spring in my Hw30. Tighter pellets always seem to shoot more accurately. Boxed CPLs are usually good but they vary too much box to box. Sometimes they're too tight and leave dents in my thumb. Also they are significantly slower in most of my rifles than exact 8.44 so ballisticly they don't make sense. That's both at the muzzle and @ 30 yds.

[Gear_Junkie]

Over the past few years.  I've found JSB 7.87's, 8.44's, and 10.3's to be consistently INCONSISTENT.  They are usually undersized, and inconsistent in head size.  I no longer buy .177cal JSB pellets.  I haven't had any issues with the AA pellets of the same weights though... go figure 

[Bayman]

Over the past few years.  I've found JSB 7.87's, 8.44's, and 10.3's to be consistently INCONSISTENT.  They are usually undersized, and inconsistent in head size.  I no longer buy .177cal JSB pellets.  I haven't had any issues with the AA pellets of the same weights though... go figure 

So what do you use?

[Gear_Junkie]

Over the past few years.  I've found JSB 7.87's, 8.44's, and 10.3's to be consistently INCONSISTENT.  They are usually undersized, and inconsistent in head size.  I no longer buy .177cal JSB pellets.  I haven't had any issues with the AA pellets of the same weights though... go figure 

So what do you use?

AA 7.87's and 8.44's in the TX200
AA 10.3's in the Regal and HW50S

[Bayman]

Over the past few years.  I've found JSB 7.87's, 8.44's, and 10.3's to be consistently INCONSISTENT.  They are usually undersized, and inconsistent in head size.  I no longer buy .177cal JSB pellets.  I haven't had any issues with the AA pellets of the same weights though... go figure 

So what do you use?

AA 7.87's and 8.44's in the TX200
AA 10.3's in the Regal and HW50S

In the past I've found the AA Falcons more accurate than Exact RSs in one of my Hw30s. But I recently bought the AA 7.87 and 8.44 and when comparing them to the JSB equivalents in my 2 Hw30s, 50 and 95 the AA have a larger extreme spread. Only shooting out to 25 yards I don't see any difference in accuracy. Maybe if I stretched it out to 50yd one might prove better. Also I'm not measuring the heads on any of them. I'm comparing the way they fit in the leade which has more to do with the skirt diameter on these particular pellets. The AA do seem to fit slightly snugger which may account for the wider ES. I'm taking my 50 to the range today I'll try them both at 25 and 50 yards.