Using 4.52mm 8.4 grain JSB Exacts and Air Arms do "straight from the tin"?



Author Topic: Using 4.52mm 8.4 grain JSB Exacts and Air Arms do "straight from the tin"?  (Read 279 times))

Offline nced

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I've noticed that a large percentage of field target shooters use the 8.4 grain JSB Exacts and many users score very well.

A while back I bought 8 tins of supposedly 4.52mm 8.4 grain JSB Exacts and found that they were one of the most inconsistent pellets I tried (weight and head size). I'm wondering how many field target shooters actually use the Exacts "straight from the tin" or are most shooters only shooting sorted lots. When using the supposedly 4.52mm Exacts during a field target match using my .177 Beeman R9 I had two dry fires during a match and would have has three if I didn't notice the loose Exact flipping out of the leade when relatching the barrel!

My tins of JSB Exacts..........


A couple seasons ago I bought a .177 HW95 and noticed that the leade was tighter than my .177 R9 and so tight that I actually made up a couple pellet head sizers to reduce my CPL heads from the usual 4.53mm-4.55mm down to 4.50mm simply to make pressing them into the leade easier on the "loading finger"........


Well, recently I ordered 4 tins of 4.52mm 8.4 grain Air Arms Domes to see how they would shoot from my tighter leade and was delighted to find that they fit consistently in the HW95 leade and actually shot "pretty good for me" upstairs sitting on a bucket resting the gun on cross sticks..........

Just for grins I then sized a few AA dome heads using my 4.50mm home made "pellet head sizer" and was again surprised that all AA pellet heads were large enough to be resized to 4.50mm (most measured 4.51 from the tin using my digital caliper) whereas the majority of supposedly 4.52mm JSB Exact pellet heads were too small to be sized using the same home made die. Out of curiosity I shot another 18 yard "bucket and sticks" 5 shot group using the AA domes with heads sized to 4.50mm (according to my digital caliper) and another 5 shot group using unsized AA domes and this was the result...........

Notice that the "unsized group" was similar to the first unsized group, however since the shooting was done "bucket and sticks" I wouldn't claim that the nice round "head sized group" wasn't any more than "luck of the draw".

Anywhoo.......back to my original question concerning shooters using JSB Exacts.......do any shoot them straight from the tin or sorted matching lots?



Offline Gear_Junkie

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Ed, I gave up on the JSB 8.44gr pellets for issues like you are experiencing.  I tried multiple tins from different sellers.  All of the tins had inconsistent head sizes.  In most cases, the heads were too small.  I have found the 7.87's and 10.3's to be more consistent, but I still shoot the AA version just to be safe.  AA Pellets have been very consistent (as have all of the H&N pellets that I've tried).
  • Nevada City, CA
.177 Daystate Regal XL & Hawke Airmax 30 SF 6-24x50
.177 HW50S, Vortek 10fpe Kit, & UTG 3-12x44 Compact SWAT Rifle Scope

Offline Marc In Iowa

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I tested about 17 different pellets in my Bantam Hi Lite 177. The three best are:

GTO   6.80 gr lead-free
JSB    8.44 gr Exact
H&N 10.65 gr Baracuda Match

The best overall (25 & 55 yds) came from the one tin I had of JSB Exact marked 4.52 head size; shooting at ~880 fps.

I just got three more tins of the 4.52 and one of the 4.53 head size. In reading up on the Exact, I find various shooters talking about the variability of size and weight.

I'm trying to decide what I want to do. I think I'll begin by weighing pellets and shooting them by weight first to see if groups are tighter.

I'm interested as well to hear from other shooters.
  • USA, Iowa, Cedar Rapids
Until human nature changes, accurate shooting is needed. Please support the CMP mission.

Lead-free plinking (20-82 yds):
- Discovery 22, HPA w/GTOs <- best HPA
- GAMO Urban 22, HPA w/GTOs <- goto plinker
- Hammerli 850 177, COČ w/GTOs <- accurate!
- Walther Terrus 177, springer w/GTOs <- fun!
Hunter Field Target (10-55 yds)
- Bantam 177, HPA w/10.65, 8.44, GTOs

Offline buldawg76

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I have found the same thing with my JSB 8.44s being grossly undersized for the size marked 4.52 on the tins. The AA 8.44s are better but still not consistent with the size 4.52 designation on the labels. The JSB are barely 4.50 with the majority being 4.48, 4.49 and very few over 4.50 . The AAs at least have quite a good amount at the 4.51-4.52 heads on them. I do not weight pellets as a rule so no info there. I just ordered some 4.53 head size JSB in hopes of getting head sizes closer to the 4.51-.52 head sizes but again mostly 4.48-.49 sized with very few at 4.51 and even less at 4.52 and no 4.53 to be found in 3 tins. So out of 1500 pellets I found only 206 4.53 head sized pellets. Pitifully inconsistency for sure.

I have a B40 (TX 200 clone) that has a loose barrel and needs no smaller than 4.51 heads with 4.52-.53 preferred. I found it likes the H&N FTTs in 4.52 best so far for available pellets in 2018 so ordered bunch of them.

Not sure what has happened with this weight of JSBs but if I did not have other guns that shoot them well I would not be buying anymore in the future. Hope they get there act together soon.

Mike
  • Oxford, Alabama
Benjamin Marauder 177 in Boyds blaster stock 
Benjamin Marauder25 Wicked Air rifles bottled
Hatsan 22 AT 44S10 long
FWB 124 177 Tuned
FWB 300s Match L 177 Tuned
FWB 300s Match Junior 177 Tuned
Diana 48 177 Vortek Tuned
BAM 40/TX hybrid 177 Vortek Tuned
Xisisco 60C PCP Tuned
Benjamin Titan NP 22 Tuned GRT trigger
Crosman Titan GP 22 Tuned GRT trigger
Crosman Venom 177 Tuned GRT trigger
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Offline Gear_Junkie

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The JSB are barely 4.50 with the majority being 4.48, 4.49 and very few over 4.50 . The AAs at least have quite a good amount at the 4.51-4.52 heads on them.
Mike

Yep, this is my experience exactly with both brands of pellets in the 8.44 size.
  • Nevada City, CA
.177 Daystate Regal XL & Hawke Airmax 30 SF 6-24x50
.177 HW50S, Vortek 10fpe Kit, & UTG 3-12x44 Compact SWAT Rifle Scope

Offline buldawg76

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My AA 8.44s are 2 years old so I may have some before the poor QC surfaced.

Mike
  • Oxford, Alabama
Benjamin Marauder 177 in Boyds blaster stock 
Benjamin Marauder25 Wicked Air rifles bottled
Hatsan 22 AT 44S10 long
FWB 124 177 Tuned
FWB 300s Match L 177 Tuned
FWB 300s Match Junior 177 Tuned
Diana 48 177 Vortek Tuned
BAM 40/TX hybrid 177 Vortek Tuned
Xisisco 60C PCP Tuned
Benjamin Titan NP 22 Tuned GRT trigger
Crosman Titan GP 22 Tuned GRT trigger
Crosman Venom 177 Tuned GRT trigger
Taipan Mutant Standard 22, BSA FFP 4x14x44 scope




Bikes, Guns and Family is all I need for a good day

Offline gonzav

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I shot my best FT scores using JSB 4.53mm Exacts 8.44 grains straight from the tin. They are snug in my LGU. I even got five shot half inch group at 55 yards while sighting in before an FT match. I had also good performance with the 2018 batch of Air Arms Diabolo Fields 4.52mm 8.4 grains. I have no patience with measuring and weighing my pellets. I shoot them if they consistently knock down a field target at 55 yards in the wind.
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FWB 300S .177, 8.2 FPE, Athlon 6-24x50 Talos
Walther LGU .177, 11.5 FPE, Krytox, Sightron 10-50x60mm FTIRMOA, Rowan trigger
Air Arms Alfa Proj .177 Pistol, RH Adj. Grip, Millett SP1 Red Dot
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Offline Brazos

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My TX200 I use for FT likes them.  Makes zero difference if they are JSB or AA version of the 8.44.  I always order the 4.52 head size.  I shoot them straight from the tin.  I agree when running them thru the Pellet Gauge they are not nearly as consistant as the CPL pellets out of the brown box I have gauged.  I typically use the AA version as they are cheaper than the JSB labeled tins.  No other reason.  I would gladly shoot the JSB 8.44 if the cost the same as the AA 8.44.

When it come to pellets, quality pellets from any brand, I tend to think you need to look at quality over a long period of time.  In my mind the pellet factory could be cranking out thousands of great pellets day after day and then Joe Blow, the pellet master, goes on vacation for a week or two and things run amuck and thousands get out that aren't up to snuff.  Or Shiela the head pellet inspector gets the flu and is out for the week and her underlings just let whatever thru as they are looking at Facebook on their phones because the boss is away.  Or maybe the pellet machines get out of wack, just a little, and thousands of pellets get out before they figure it out.  I really wish they would put a date stamp on the pellets letting us know what day they were made.  Then if people got on here with complaints we could compare the dates they were made.  I bet, and maybe I am just stupid, that we could all buy a certain pellet from different suppliers and if we were all to inspect them for quality the bad tins were made on a certain day or a defined date range.  I am talking quality pellets here and not crappy ones where they don't care and crank them out.
« Last Edit: November 13, 2018, 09:43:27 PM by Brazos »
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Offline nced

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My TX200 I use for FT likes them.  Makes zero difference if they are JSB or AA version of the 8.44.  I always order the 4.52 head size.  I shoot them straight from the tin.  I agree when running them thru the Pellet Gauge they are not nearly as consistant as the CPL pellets out of the brown box I have gauged.  I typically use the AA version as they are cheaper than the JSB labeled tins.  No other reason.  I would gladly shoot the JSB 8.44 if the cost the same as the AA 8.44.

When it come to pellets, quality pellets from any brand, I tend to think you need to look at quality over a long period of time.  In my mind the pellet factory could be cranking out thousands of great pellets day after day and then Joe Blow, the pellet master, goes on vacation for a week or two and things run amuck and thousands get out that aren't up to snuff.  Or Shiela the head pellet inspector gets the flu and is out for the week and her underlings just let whatever thru as they are looking at Facebook on their phones because the boss is away.  Or maybe the pellet machines get out of wack, just a little, and thousands of pellets get out before they figure it out.  I really wish they would put a date stamp on the pellets letting us know what day they were made.  Then if people got on here with complaints we could compare the dates they were made.  I bet, and maybe I am just stupid, that we could all buy a certain pellet from different suppliers and if we were all to inspect them for quality the bad tins were made on a certain day or a defined date range.  I am talking quality pellets here and not crappy ones where they don't care and crank them out.
After weighing, measuring & sorting thousands of pellets (JSB Exacts and H&N FTTs) I've come to the conclusion that as long as the barrel leade is tight enough to "size" a pellet head when loading, it really doesn't matter much what that final 1/100th of a mm is. The issue I had was that I was trying to shoot Exacts and FTTs from my .177 Beeman R9 which has a rather loose bore. The brown boxed 7.9 grain CPLs with 4.53mm-4.55mm heads fit/shot perfectly, however the issue with UNEXPLAINED fliers came when shooting undersized pellets that fit loose in the leade. After noticing MANY JSB & FTT loose fitters in the R9 lead both pellet brands were nixed and I reverted back to brown box CPLs.

After buying a .177 HW95 a couple seasons ago I noticed that the bore was tighter than the R9 and I started sizing my CPL heads to relieve the "sore loading finger" when trying to shove a 4.55mm hard lead CPL into the leade. I did buy a second .177 HW95 barrel from the Canadian retailer that was selling off their HW inventory and found that it seems HW has reduced it's .177 bore diameter because a new CPL fit the leade as tightly as the barrel that came with my HW95.

It's interesting to read of your good results shooting 4.52mm Exacts directly from the tin considering the great variation in pellet head sizing with the tins I had. When I was measuring a few thousand 8.4 grain 4.52mm JSB Exacts there was a small percentage that actually measured 4.52mm, however I also measured pellets from the single tin of 4.52mm AA domes and finding a much higher percentage of pellets actually measured 4.51mm-4.52mm. Pellet head dimensions seem to vary enough that a lot of shooters sort their pellets using "holes in a plate" claiming better accuracy from one size group vs the others.

Thanks for the feedback!


Offline buldawg76

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nced

My bore in the B40 mirrors your with being loose and finding that only CPLs and 4.51-4.53 JSB/AAs. My bore may be a bit looser than yours since it really like the boxed CPL I have from die 7 dated Dec 14 2004. I am about out of the CPLs so tried some 4.53 JSBs only to be very disappointed in sizes and consistency. I found that the 4.53 H&N FTTs are far more consistence in size and shoot very well from the B40 so those will be my choice from now on.

The CPLs also measure the 4.53-4.55 that you have recorded. But from reading about the newer CPLs being much like the JSB/AA QC. I am hesitant to buy a box from todays dies for that reason.

All my other .177s shoot the JSB/AAs fine so at least they are not going to waste.

Mike
  • Oxford, Alabama
Benjamin Marauder 177 in Boyds blaster stock 
Benjamin Marauder25 Wicked Air rifles bottled
Hatsan 22 AT 44S10 long
FWB 124 177 Tuned
FWB 300s Match L 177 Tuned
FWB 300s Match Junior 177 Tuned
Diana 48 177 Vortek Tuned
BAM 40/TX hybrid 177 Vortek Tuned
Xisisco 60C PCP Tuned
Benjamin Titan NP 22 Tuned GRT trigger
Crosman Titan GP 22 Tuned GRT trigger
Crosman Venom 177 Tuned GRT trigger
Taipan Mutant Standard 22, BSA FFP 4x14x44 scope




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Offline nced

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nced

My bore in the B40 mirrors your with being loose and finding that only CPLs and 4.51-4.53 JSB/AAs. My bore may be a bit looser than yours since it really like the boxed CPL I have from die 7 dated Dec 14 2004. I am about out of the CPLs so tried some 4.53 JSBs only to be very disappointed in sizes and consistency. I found that the 4.53 H&N FTTs are far more consistence in size and shoot very well from the B40 so those will be my choice from now on.

The CPLs also measure the 4.53-4.55 that you have recorded. But from reading about the newer CPLs being much like the JSB/AA QC. I am hesitant to buy a box from todays dies for that reason.

All my other .177s shoot the JSB/AAs fine so at least they are not going to waste.

Mike
Die #7 cases that I bought were the ones that had poor QC and many pee-wees so I would check the fit in my .177 R9 leade prior to putting them in my pellet pouch. Waaaay back then I didn't get real fancy with measuring and weighing CPLs, I simply dropped them into the R9 leade and if they visually sat at the proper height they were used. If a pellet visually sat too low in the leade it was tossed out. LOL....one box from the die #7 case contained over 100 (don't remember the exact number) pee-wees. Of those pee-wees three dozen were so small that they literally "free fell" through the bore, even past the choke. I do have to mention however that the CPLs passing the "fit in the leade test" were very accurate and I put up with the hassle because no other brand of pellet I tried was as accurate as a good fitting CPL.

10 years after the die #7" case in 2014 I received a case of CPLs (die "A" I think) and they were consistent in size and weight (had scale and good digital caliper then), however the pellets were coated with too much parting compound (looked like powdered graphite) and since I lube my hard lead Crosman pellets I found that the mixture of excess parting compound and Slick 50 OneLube would kinda "goop up" my bore so that case was washed and dried before lubing. That case of CPLs was the reason I tried both 4.52mm (supposedly) JSB Exacts and H&N FTTs and ended up the tedious sorting so I wouldn't load and shoot one "less than snug" pellet followed up with a pellet that was really loose in the leade.

Anywhoo.........after trying the FTTs & JSBs I determined to revert back to boxed CPLs and wash them if needed, on June 2015 I ordered 4 cases  of CPLs. I was pleased to note that the cases of die "B"s were actually clean not needing washing before lubing and I only have 3 boxes left. Even ordering one case of CPLs from Pyramyd Air using their "buy 4 & pay for 3" deal is a pretty expensive proposition so I preferred ordering the AA domes in the 500 count tins using the "buy 4 pay 3" PA deal. Actually when I checked the cost per pellet of a case of CPLs (5000 pellets) vs 4 tins of AA Domes (2000 pellets) I found that the AA domes were a tad more expensive per pellet but not enough that I would buy the CPLs if the AA domes were accurate. I haven't tested the AA pellets at longer ranges yet (rotten NC weather for a while now). From the tighter bore HW95 the AA do shoot well upstairs at 18 yards so I'm hopeful that they are accurate at 50 yards.

I haven't tried the AA domes from my looser bore .177 Beeman R9 but they might even work well from that gun. When I was sizing pellets for the HW95 I found that a CPL with the head reduced to 4.50mm shot well from both the HW95 and the R9. Since I found that my 4.50mm sizer actually reduced almost all 2000 AA Domes from 4.51mm to 4.50mm, I'm thinking that they might be a "one pellet for both guns".

Here are a few 50 yard groups I shot "bucket and sticks" with the R9 comparing CPLs to a couple different AA domes (8.4gr & 7.3) and the R9 didn't like the lighter 7.3s............

The AA 8.4 grain 4.52mm 50 yard group wasn't bad at 1"ish ctc, however the CPL group was 1/2"ish ctc.

Offline buldawg76

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Hmmm, That's interesting that the die 7 CPLs you had were not consistence in sizes since my only box of die 7 are very consistent at 4.53 to 4.55. For me it makes buy any hew boxes a &^^& shoot with no guaranty they will be good or not. Since I found the B40 shoots the FTTs good it a moog point for me now to consider the CPLs. I do not have any other guns that require pellets are on the large end of the scale.

I agree that there is not enough price difference to warrant trying to save a few pennies as well. I will continue to monitor threads to see if crosman gets there act together in the future. Not holding my breath though.   

Mike
  • Oxford, Alabama
Benjamin Marauder 177 in Boyds blaster stock 
Benjamin Marauder25 Wicked Air rifles bottled
Hatsan 22 AT 44S10 long
FWB 124 177 Tuned
FWB 300s Match L 177 Tuned
FWB 300s Match Junior 177 Tuned
Diana 48 177 Vortek Tuned
BAM 40/TX hybrid 177 Vortek Tuned
Xisisco 60C PCP Tuned
Benjamin Titan NP 22 Tuned GRT trigger
Crosman Titan GP 22 Tuned GRT trigger
Crosman Venom 177 Tuned GRT trigger
Taipan Mutant Standard 22, BSA FFP 4x14x44 scope




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Offline Brazos

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[/quote]
After weighing, measuring & sorting thousands of pellets (JSB Exacts and H&N FTTs) I've come to the conclusion that as long as the barrel leade is tight enough to "size" a pellet head when loading, it really doesn't matter much what that final 1/100th of a mm is. The issue I had was that I was trying to shoot Exacts and FTTs from my .177 Beeman R9 which has a rather loose bore. The brown boxed 7.9 grain CPLs with 4.53mm-4.55mm heads fit/shot perfectly, however the issue with UNEXPLAINED fliers came when shooting undersized pellets that fit loose in the leade. After noticing MANY JSB & FTT loose fitters in the R9 lead both pellet brands were nixed and I reverted back to brown box CPLs.

After buying a .177 HW95 a couple seasons ago I noticed that the bore was tighter than the R9 and I started sizing my CPL heads to relieve the "sore loading finger" when trying to shove a 4.55mm hard lead CPL into the leade. I did buy a second .177 HW95 barrel from the Canadian retailer that was selling off their HW inventory and found that it seems HW has reduced it's .177 bore diameter because a new CPL fit the leade as tightly as the barrel that came with my HW95.

It's interesting to read of your good results shooting 4.52mm Exacts directly from the tin considering the great variation in pellet head sizing with the tins I had. When I was measuring a few thousand 8.4 grain 4.52mm JSB Exacts there was a small percentage that actually measured 4.52mm, however I also measured pellets from the single tin of 4.52mm AA domes and finding a much higher percentage of pellets actually measured 4.51mm-4.52mm. Pellet head dimensions seem to vary enough that a lot of shooters sort their pellets using "holes in a plate" claiming better accuracy from one size group vs the others.

Thanks for the feedback!


[/quote]

Ed I think you and I pretty much agree on pellets.  I believe in that same snug fit and love CPLs.  I can't say I have measured them by the thousands but the ones I have have been pretty consistant.  Much more than JSB/AA.  I have found my HW rifles love CPLs.  Strangely I picked up a new HW35 a couple seasons ago, and like your newer R9 the bore on it is tight (CPLs still shoot good out of it).  When I got started in this stuff around 2003 I bought an R11.  It shot CPLs and Beeman FTT (nowadays HN FTT) great.  I was shooting in silhoette matches and everybody raved about JSB pellets.  I bought some and they shot like &^^&.  They didn't have that snug fit like the CPL.  Therefore I wrote them off.  I also picked up Daystate CRX around that time and it loved CPH and Barracuda Match.  As a FT match director I also noticed the overwhelming amount of people using JSB/AA pellets and started buying some to do some further testing.  I found it just depends on the rifle.  Turns out my Daystate CRX likes the JSB Heavies.  My HW30 loves the JSB 7.33.  My R11 still doesn't care for JSB.  My TX200 likes JSB 8.44 but to be honest likes CPL and HW FTT.  I settled on the JSB for the TX at the time because I had a bunch and by the time all the work went into setting up the rifle I just rolled with them.  I do find all my rifles shoot CPL and HN FTT very well.  I don't think CPL or CPH get the respect they deserve.  In fact I bought a new R10 over the summer and tried a bunch of pellets and it shoots CPH the best.  Something about JSB/AA that are different and I think gave me a false impression in the beginning.  They fit into the barrel easy.  But the lead is soft and have a thin skirt.  The Crosman and H&N have a much thicker skirt and more robust design.  In the beginning I just thought the JSB pellets had a small head size but it's just the soft lead/thin skirt design.
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Offline Marc In Iowa

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So far, my 177 Bantam Hi Lite likes the JSB Exact 8.44 grain pellets the best overall for 25 and 55 yds (from 17 different pellets and sizes); 10 shot groups, 8 mph wind, 38°F, ~883 fps.

25 yds .48" CTC
55 yds .81" CTC

Sitting on a stool, in the corner of my deck railing, front bag rested, each elbow testing on the railing on the corner (sort of like a "bucket and sticks" Field Target hold). This is all from using my single shot tray. Magazine loading can be double these results.

Today I tested two head sizes straight out of the tin at 25 yds.

4.52mm .48"
4.53mm .83" (73% bigger)

Last night, I tried using my $7.50 digital calipers to measure accurate head sizes. Sadly, I could measure the same pellet 10 times and get 6 different widths. Either my process or my calipers (or both) are inadequate to this task.

It seems strange to me that two tins of the same pellet that are marked as only different by .01mm should produce such radically different group sizes.

But there you are.
« Last Edit: November 14, 2018, 10:43:44 PM by Marc In Iowa »
  • USA, Iowa, Cedar Rapids
Until human nature changes, accurate shooting is needed. Please support the CMP mission.

Lead-free plinking (20-82 yds):
- Discovery 22, HPA w/GTOs <- best HPA
- GAMO Urban 22, HPA w/GTOs <- goto plinker
- Hammerli 850 177, COČ w/GTOs <- accurate!
- Walther Terrus 177, springer w/GTOs <- fun!
Hunter Field Target (10-55 yds)
- Bantam 177, HPA w/10.65, 8.44, GTOs

Offline nced

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So far, my 177 Bantam Hi Lite likes the JSB Exact 8.44 grain pellets the best overall for 25 and 55 yds (from 17 different pellets and sizes); 10 shot groups, 8 mph wind, 38°F, ~883 fps.

25 yds .48" CTC
55 yds .81" CTC

Sitting on a stool, in the corner of my deck railing, front bag rested, each elbow testing on the railing on the corner (sort of like a "bucket and sticks" Field Target hold). This is all from using my single shot tray. Magazine loading can be double these results.

Today I tested two head sizes straight out of the tin at 25 yds.

4.52mm .48"
4.53mm .83" (73% bigger)

Last night, I tried using my $7.50 digital calipers to measure accurate head sizes. Sadly, I could measure the same pellet 10 times and get 6 different widths. Either my process or my calipers (or both) are inadequate to this task.

It seems strange to me that two tins of the same pellet that are marked as only different by .01mm should produce such radically different group sizes.

But there you are.
Concerning measuring pellet heads............
1st............
 I bought an IGaging digital caliper that's advertised to be accurate to .0005"/.01mm
http://igaging.com/page12.html

It's about half the price of a Mitoyo but it does seem to be OK for my purposes.

2nd..........
I only measure pellet heads at one spot on the jaws.


3rd.......
The caliper is flat on my Formica desk top so the jaws only meet the pellet heads.


4th........
To get a consistent read the jaws are closed gently just to the point that a pellet can be slid on my Formica desk top.


5th......measuring pellet heads IS a pain and I prefer to size my pellet heads so all have the same head size whatever it actually is. LOL....I have no notion that when my caliper reads 4.50mm that it's really 4.50mm due to the caliper unit roundoff, however as long as the pellet head is consistent and shoots accurately I really don't care. Another benefit of "head sizing" is the fact that it only takes 5 casual seconds to size a pellet head while watching airgun YouTube videos. ;D

LOL.....I finished sizing 4 tins of the 4.52mm AA Domes which measured 4.51mm with my digital caliper and head sized to 4.50mm finding 1 tin that was dented on the corner. That tin had about a dozen pellets with squished skirts........


I do have to mention that pellet heads sorted using my measuring method do fit consistently in the leade without sizing and as long as the sorted pellets fit the leade snugly the minor "measuring tolerances" will be "ironed out" when pressed into the leade.

By the way, here are a few CPL die "B" pellets dated Feb 3, 2014 randomly taken from one of the cardboard boxes.........

Pretty consistent for sure!
 

Offline HectorMedina

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Perhaps it is important to mention that in the same way you shouldn't compare apples and oranges, you shouldn't compare CPL/CPH pellets to the "normal" pellets like JSB or H&N FTT's.
PERHAPS, you could compare CP's with H&N Snipers, or BHE's (which are sort of hybrid), but remember that one style of pellets seals on the head (CP's) and the other seals at 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

For years, CP's were THE standard by which all other pellets were measured, not anymore. The head sealing design is harder to keep to a tight spec. and while the design is still very worthwhile, "Velocity Outdoors" (current official name  of the old Crosman Corp.) seems intent on keeping those pellets as relatively inexpensive offerings with the attending QC problems.

So, having gone through the difference between two styles of pellet designs, let me say that measuring the head size itself as an absolute number has NO BEARING on what a barrel will like or not.
What a barrel likes or not is much more dependent on the harmonics at the muzzle than on anything else.
Making sure that the pellets you use are as uniform as possible, DOES have a beneficial effect, however, the question is whether this is the best use of YOUR time.
I have a very good friend (and excellent shooter) that works nights.  So he has all the time in the world, and carrying a small electronic balance and some pellets into the office to weigh pellets during the dead lulls is obviously a good use of HIS time, but we are not all in the same situation.

It is also true that less efficient pellets may slow the pellet down to the point where the exit point coincides with the optimum point from the muzzle harmonics oscillation side, or viceversa, and that is when small variances in MV will make a gun more or less accurate with the same pellet weight or weight range.

Now, as to NCEd's question: I use selected lots of 8.44's and 7.98's almost straight out from the tin, I just take the precaution of lubing the pellets because I don't want to clean my barrel too often.
Some lots shoot very well some lots shoot awful, I test a tin each of a number of lots and then buy whole cases. A case (50X500 pellets) will last me a season.

Our tests on Harmonics generation in different rifle designs with different powerplants and accessories (First part here: https://www.ctcustomairguns.com/hectors-airgun-blog/truly-taming-the-harmonics-in-spring-piston-airguns )
Show that those guns that are reputedly "not pellet picky" are usually those guns that do NOT generate a ton of harmonics at the muzzle.

Measuring pellet heads with the pellet gauge, weighing with a precision scale, and/or rolling the pellets on a glass plate; all have their intricacies and, in my case, time is better spent practicing.

;-)

Keep well and shoot straight!






HM

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