New tin of JSB Heavys and ... wow? What in the heck?

[subscriber]

This makes me wonder what brand, type, weight (velocity) pellets the "cleaners" shoot, VS the "never cleaners".

Based on anecdotal evidence, Crosman Premier hard lead pellets need occasional barrel cleaning, while JSB, H&N and RWS more often don't.

Is this an over simplification?

I can see that barrel smoothness and choke dimensions could also play a big role.  As well as muzzle velocity.  Some say expect leading over X FPS.  So the power and pellet weight would factor in.

[subscriber]

Add lubed pellets, or not to the cleaning question...

[nced]

This makes me wonder what brand, type, weight (velocity) pellets the "cleaners" shoot, VS the "never cleaners".

Based on anecdotal evidence, Crosman Premier hard lead pellets need occasional barrel cleaning, while JSB, H&N and RWS more often don't.

Is this an over simplification?

I can see that barrel smoothness and choke dimensions could also play a big role.  As well as muzzle velocity.  Some say expect leading over X FPS.  So the power and pellet weight would factor in.

"Some say expect leading over X FPS"
I've wondered if shooting "loosies" are partly responsible for rapid barrel fouling. There was a time years ago when boxed 7.9 grain Crosman Premiers (around die#7) had "pellet head size QC issues" and some would fit loosely in the leade. Experience proved that a loose fitting CPL would be a flier so I would shoot the "loosies" into the ground. I theorize that when shooting the combination of hard lead CPLs (antimony in the alloy), loose fit in the bore and R9 tuned to shoot at 910fps caused the rifling to strip lead shavings from the pellet head since the loose head wasn't "engraved properly" by the rifling. "Way back when" I was shooting dry hard lead CPLs (including the "loosies") I would find visible flecks of lead on cleaning patches pulled through the bore. After I started lubing the hard lead CPLs the interval between needed bore cleaning (when accuracy fell off) was reduced and I stopped seeing lead flecks on pulled patches. Also, the bore clean was much simpler because only a couple pulled patches were needed to restore accuracy instead of a thorough bore scrub.

As far as "pure lead" pellets like the JSB Exacts, I really don't know if they would foul my bores like the CPLs since almost all of the supposedly 4.52mm Exacts fit my R9 leade inconsistently loose (even had some flip out of the leade when relatching my break barrel) because there were simply too many fliers to be useful so they weren't used very much and I sold the remaining 9 tins of Exacts I owned.

Anywhoo....I personally believe that shooting loose fitting pellets will foul the bore more quickly as the velocities are pushed higher, however I don't know if the same thing would happen when "properly snug" fitting pellets are shot at higher velocities   

[Relentless Holiday]

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[Relentless Holiday]

This makes me wonder what brand, type, weight (velocity) pellets the "cleaners" shoot, VS the "never cleaners".

Based on anecdotal evidence, Crosman Premier hard lead pellets need occasional barrel cleaning, while JSB, H&N and RWS more often don't.

Is this an over simplification?

 

I am of the noncleaning (old)school, unless something changes. After the initial once over for factory oils. And i have similar pellet opinion. Cheap pellets=dirty=the guns the need it sometimes, expensive=better q.c. .... it's how it seems to go.  But I won't discount rattlers contributing now that it's been mentioned. It still fits my experiences for the past 30yrs. I have a semiauto FX gun that cycles air from the LDC back to the reciever, so wiping down inside is infrequent but regular maintenace to avoid problems. FX recomeds only JSB for good reasons. Cleaning out after shooting CPUMs is just plain messier.

To original poster, I just noticed, while ordering a bunch, that Pyramyd now specs the head size of Exact Jumbos at 5.52mm  not 5.5 as in years past, not sure since when cause i'm just finishing the last of sleeves bought back in 2007.  That much difference from old molds getting bigger is gonna change POI for me I'm sure.

[subscriber]

Ed,

Your loose pellet leading theory has definite "traction" with powder burners.  There, a less than groove diameter driving band bullet causes a significant volume of hot gas to leak past the projectile, that then melts and solders lead to the barrel (more of a problem with hard alloys because the degree to which bullet base diameter can "bump up" to seal off hot gasses is reduced). Now, spring airguns do not have the heat of powder burners, but they do heat the air beyond the melting point of lead early on in the firing cycle...

Shooting slugs from a PCP that are well below groove diameter to reduce friction (and allow less distortion in the choke) is not a leading risk, because the air leaking by the slug is "cold".  It is cooled via expansion; rather than heated in the gun via compression.

Do you "wash" pellets before lubing them?  If so, this would remove a lot of lead flakes that would be of a size that could be melted and re-condense on the steel.  If you don't "wash" pellets, or you find a significant difference in leading with one type of lube over another, then that suggests it is the lube itself that is the major contributor to keeping lead from sticking to the bore.

I am of the opinion that cleaning any barrel to the point of stripping all fouling, grease and oil down to bare steel before shooting is asking for lead to solder to the barrel...  I deliberately leave a thin film of oil, or only lightly wipe out from storage before shooting ( I look through to see shiny bore, with no cleaning patches left in it).  That way, whatever "dust" remains in the bore after a few shots cannot strongly bond to the steel.  Even better, if that oil or lube is replaced with each shot. 

With springers, oil lubed pellets are dicey due to the propensity to burn the oil via dieseling.  Certainly, one does not want a drop of oil in the pellet base.  Just a hint on the narrow bearing surfaces.  Else, a wax or some other lube that is harder to light is better.  Here, your experience in lube choices is most useful.

Patching dry is much more important with centerfire rifle cartridges.  Here it is the chamber that should be dry (so the case can grip the chamber walls), rather than that the bore being absolutely bare steel, on the first shot.

That said, all un-jacketed lead PB projectiles are lubricated to prevent leading.  This includes pure lead for muzzle loaders, and "hard cast" for centerfire handguns.

[nced]

Ed,

Your loose pellet leading theory has definite "traction" with powder burners.  There, a less than groove diameter driving band bullet causes a significant volume of hot gas to leak past the projectile, that then melts and solders lead to the barrel (more of a problem with hard alloys because the degree to which bullet base diameter can "bump up" to seal off hot gasses is reduced). Now, spring airguns do not have the heat of powder burners, but they do heat the air beyond the melting point of lead early on in the firing cycle...

Shooting slugs from a PCP that are well below groove diameter to reduce friction (and allow less distortion in the choke) is not a leading risk, because the air leaking by the slug is "cold".  It is cooled via expansion; rather than heated in the gun via compression.

Do you "wash" pellets before lubing them?  If so, this would remove a lot of lead flakes that would be of a size that could be melted and re-condense on the steel.  If you don't "wash" pellets, or you find a significant difference in leading with one type of lube over another, then that suggests it is the lube itself that is the major contributor to keeping lead from sticking to the bore.

I am of the opinion that cleaning any barrel to the point of stripping all fouling, grease and oil down to bare steel before shooting is asking for lead to solder to the barrel...  I deliberately leave a thin film of oil, or only lightly wipe out from storage before shooting ( I look through to see shiny bore, with no cleaning patches left in it).  That way, whatever "dust" remains in the bore after a few shots cannot strongly bond to the steel.  Even better, if that oil or lube is replaced with each shot. 

With springers, oil lubed pellets are dicey due to the propensity to burn the oil via dieseling.  Certainly, one does not want a drop of oil in the pellet base.  Just a hint on the narrow bearing surfaces.  Else, a wax or some other lube that is harder to light is better.  Here, your experience in lube choices is most useful.

Patching dry is much more important with centerfire rifle cartridges.  Here it is the chamber that should be dry (so the case can grip the chamber walls), rather than that the bore being absolutely bare steel, on the first shot.

That said, all un-jacketed lead PB projectiles are lubricated to prevent leading.  This includes pure lead for muzzle loaders, and "hard cast" for centerfire handguns.

A few "personal opinion only" comments.

"Now, spring airguns do not have the heat of powder burners"
Bore fouling with my HW springers and loose fitting pellets has NOTHING to do with heat. It's simply that shooting pellets that are too loose at too high of velocity strips off some lead if the pellet doesn't spin with the rifling. Then the following pellets will pack the lead particles tightly into the rifling grooves, so on and so forth with each "loosie".

"Shooting slugs from a PCP that are well below groove diameter to reduce friction"
I have no idea what happens with a PCP, I'm only reporting my findings with the springers I use. I do know however that some PCP shooters at the ft matches are satisfied that a 30fps velocity variation has little to do with accuracy out to the 55 yard max target distance. On the other hand I TRY to keep my velocity variation prom pellet to pellet at no more then 10fps. For some reason even a 20fps velocity variation from my recoiling piston guns does affect the accuracy at longer distances. I really don't know why but I suppose the way springer recoil "flips the pellet when shot" weighs into the mix due to greater or lesser "muzzle flipping" if the velocities aren't relatively consistent. I tried using Chair Gun ballistic software to determine the ballistics of my pellets but gave up. The reason was that unless I played with the BC numbers in the software the "puter results" weren't very close to "real world" and I had to shoot at actual distances to determine the pellet trajectory. I've READ that some PCP shooters were able to take the computer calcs and actually use the data for plotting trajectories. Perhaps the motion of piston guns introduce "dynamic variables" in ways that can't be computed so I've always shot some targets at actual distances to verify the "puter results". LOL....I needed to shoot pellets for verification so I decided to skip the "puter calcs" and simply shoot real targets like this one. LOL....it was even shot sitting on a bucket resting the gun on cross sticks like I do when squirrel hunting or shooting hunter class field target because I get different results if I shoot from a bench..........
   

Do you "wash" pellets before lubing them?
Only if they're dirty, have too much parting compound on them, or there is a lot of swarf in the box. I couple cases of Crosman Premiers that I've bought a few years ago were washed due to "gunge in the box" but the cases bought for in the last few years have been clean without swarf in the box or on the pellets.

"lube itself that is the major contributor to keeping lead from sticking to the bore."
Yup....exactly which is why I started lubing my CPLs in the first place.

"I deliberately leave a thin film of oil, or only lightly wipe out from storage" and "Even better, if that oil or lube is replaced with each shot. "
Shooting lubed CPLs the bore is "oiled" by every pellet shot.

"With springers, oil lubed pellets are dicey due to the propensity to burn the oil via dieseling."
Definitely true and there needs to be some care when lubing to insure that only the "rifling surfaces" are lubed. Basically, don't spray lube directly on the pellets. To assure this I spritz a tiny amount of Slick50 OneLube in the bottom of a dedicated pan, then spread the "oil film" around evenly over the bottom of the pan, dump in a box of CPLs, stir pellets gently so a thin film of lube is transferred to the rifling surfaces, then dump the pellets back into the box (or pellet pouch) for storage. If there is a Greyhound Bus stop smell when shooting OR EVEN more than a slight sheen on the loading fingers the pellets were excessively lubed. Here is a box of CPLs being lubed........


"That said, all un-jacketed lead PB projectiles are lubricated to prevent leading."
Over the years I've found that there is very little "powder burner lore" that applies to shooting pellets. For example, when chronying some .22 rimfire bullets I've had velocity variations as much as 100fps. On the other hand, after tuning my springers and a few dozen "fouling shots" (yep, my springer bores do need some fouling to be consistent) I check the velocity consistency.

I recently (last week) checked out the velocity of my .177 R9 and .177 HW95 and here were the results indicating no abnormal dieseling even though both pellet brands were lubed.......
.177 Beeman R9.....7.9 grain CPL 849,844,849,850     8.4 grain Air Arms domes 839,839,836,833

.177 HW95.............7.9 grain CPL 881,881,884,887      8.4 grain Air Arms Domes 856,859,860,862       

 

 


 

[subscriber]

Wow, Ed.  If the pellets can skid in the rifling they really are loose.  Too loose.  Makes me think of this guy: Toulouse Lautrec 

I think you are correct that velocity variations with springers affect POI, not because of a difference in pellet drop over range, but because of differences in barrel whip timing and muzzle placement on leaving the bore.   That said, such a small velocity variation between shots suggests no dieseling in your springers at all.

[nced]

Wow, Ed.  If the pellets can skid in the rifling they really are loose.  Too loose.  Makes me think of this guy: Toulouse Lautrec 

I think you are correct that velocity variations with springers affect POI, not because of a difference in pellet drop over range, but because of differences in barrel whip timing and muzzle placement on leaving the bore.   That said, such a small velocity variation between shots suggests no dieseling in your springers at all.

If there is dieseling it's only because some OneLube may have gotten inside the pellet skirt. My springers were both stripped of all petroleum lubes and then relubed with non-dieseling Dupont Krytox GPL205 grease. I have found that as long as my velocity doesn't vary much more than 10fps I can't tell and accuracy difference with my equipment and shooting skills sitting on a bucket resting the gun on cross sticks.