Back on topic:
The only time I've ever seen JSBs shoot as badly as in the picture posted was when the wrong caliber pellet was used (a 4.5mm pellet in a 5.0mm barrel ... @Edradour, memba?) And seeing as how the other 4.5mm pellets shoot decently (so the caliber isn't the problem) my conclusion is that the tin of JSBs you had were damaged. The majority of bench and FT Proteas shoot JSB pellets; they wouldn't do so if the pellets were junk. Get another tin and try that.
IME, my HW97 really liked the JSB Express pellets. These were 4.52mm pellets and didn't fit as tight as the 4.53mm Exacts.
H&N and Crosman are known to be a "harder" pellet and therefore feel tighter going into the barrel, even though they're all marked as 4.52mm.
As for cleaning, my FT rifle likes to have its barrel cleaned about every 500 pellets (I can notice the accuracy decreasing after a tin), but I also had an S400 that didn't care if I cleaned it or not - it shot brilliantly either way. You'll need to decide when / if to clean based on your experience with your rifle.
Thanks Mark_F, those are some great points and thanks for bringing us back on topic.
It must have been a typo - I think Dale was referrring to WP40 (Weasel Piss 40) not the WD40 we use here in SA.... hehe. Sorry couldnt resist that one.
On the calibre - I definitely have a .177 calibre HW97K. I will try another tin of JSB as Ive only heard good things about JSB through a Weihrauch. I must have just gotten really unlucky. The pellets looked perfect though, there was no bending or damage. They were by far the cleanest best formed pellets Ive ever laid eyes on which is why I was so shocked by that random grouping.
I think Im going to hold off on cleaning for now, I'll see if the rifle settles down on its own. The groupings seem to be getting tighter the more I shoot it and its been about 200 - 300 pellets now. I really want same hole accuracy from it, especially at 15 meters.
@DvdM, good point about the Nitrosolvent - I hadnt thought of that. We used to use it back at school with some steel wool to remove rust from the outside of rifles as well as down the barrel with a patch and rod, so I had assumed it was just to remove corrosion and lead build up.
DvdM's method is pretty much the same as mine, I do however use the "lead removal cloths" sold in gun shops as pull throughs for a first time clean.
Also a tune by Jaco (JacoWP on the forum) is not a bad idea.
Go and do some research on WD40 and its use on guns.
There are those that think it is great and other who don't. Some gun makers recommend it, others do not.
From my own experience I am not enamoured with it for using on guns.
As a water displacement product it does exactly what it says on the tin.
You will probably find your gun likes the 4.53 JSBs.On the calibre - I definitely have a .177 calibre HW97K. I will try another tin of JSB as Ive only heard good things about JSB through a Weihrauch. I must have just gotten really unlucky. The pellets looked perfect though, there was no bending or damage. They were by far the cleanest best formed pellets Ive ever laid eyes on which is why I was so shocked by that random grouping.
Also, I don't know how experienced a (springer) shooter you are, but random groups and confusion are a fact of life with even the best guns, if you don't do the right things at the right time. Check YOURSELF (technique etc.) before you check the gun.
Another VERY critical factor for tight groups with a spring gun is your trigger setting. You need to have the right balance between weight and break, otherwise you will struggle with consistency. Factory triggers are set for safety rather than shooter goals.
As far as DW40 and O-rings go, if everyone has their opinion it is time we settle this for once and all, take a container fill it (or just spray some in) with WD40 and put some O-rings in there and see for yourself what happens. Leave it for a week, month or longer and see if the O-rings disintegrate or what happens. Put a few different rubbers in there, normal ones and Nitrile and any other type that can be had freely at BMG or wherever you buy O-rings.
Thanks again for the input everyone.
Seeing as though we are on lubricants and cleaners - what is a good oil to use as a protective film on the outside of the rifle after a day of shooting? Im talking about something you could use on a rag to give the rirfle a wipe down to get rid of fingerprints and sweat etc... Just to be clear, Im talking about external metal surfaces only.
Ive read Q20 or WD40 is fine, but some posts mentioned it attacks the blueing? In my mind just a simple oil makes sense? I went to a gunshop and they gave me a free sample of some "Trisil" gun oil, but Im assuming because of the name "Tri" there is probably more than just oil in it?
Does anybody have experience with "Trisil" as a wipe down, external oil? What else is commonly used here in SA?
I just use a simple gun oil, but applied very sparingly to a cloth and just give it a wipe over, you don't want it dripping wet with oil.
If the rifle has got wet I will remove the stock and make sure it is dried off thoroughly first.
Be a touch cautious with oils on woodwork as some mineral oils can cause damage to the wood.