Weihrauch HW100 T has become completely inaccurate

[gingernut]

I’m with Murphy on your pellet choice.

R10 are match pellets for short range low power target work.
They come in rifle and pistol variants.
They will also probably be a bit loose in your barrel.
Superfields are not great either.

Try Air Arms Diablo Field in 4.52.
Or H&N ftt.

After you have cleaned your barrel the gun will take quite a few shots to settle down with any pellet.
As it does when you change pellet.

[jepho]

I’m with Murphy on your pellet choice.

R10 are match pellets for short range low power target work.
They come in rifle and pistol variants.
They will also probably be a bit loose in your barrel.
Superfields are not great either.

Try Air Arms Diablo Field in 4.52.
Or H&N ftt.

After you have cleaned your barrel the gun will take quite a few shots to settle down with any pellet.
As it does when you change pellet.

I have had outstanding results with R10s. Pellet on Pellet at 25 yards. They make a range of sizes and 4.52 was as close fitting as I could use in my gun.

The H&N FTTs were also excellent and I used these when I first bought the gun and periodically since. Look at the images I have linked below. The 25 yard group of 5 shots, pellet on pellet, tells me that I must be doing something right. The subsequent scattergun targets with the appended text show me that something is amiss with the gun, rather than the pellets, of which I have tried several very well known makes, as I had listed previously.

I cannot understand why people are trash talking RWS R10s other than their own prejudices. I have found them to be a fantastic pellet for removing yet one more variable. In one 500 pellet tin for my pistol, I found one pellet which did not weigh 7.0gr. it was 7.1gr. That tells me something about the care taken in the manufacturing process and the subsequent quality assurance processes of RWS.

Of course, your own mileage may very well vary from mine but... forgetting your own experiences with pellets and guns for a moment - My experience with the pellets mentioned has been nothing but fantastically accurate. It now is not the case and for no obvious reason. I am trying to find out what that reason is because it is clearly something which has changed in the gun. This rifle has been used every week for 18 months without missing a beat.

Please excuse me for saying that the pellets I have chosen to use; appear (to my mind) to have absolutely nothing to do with the change in performance that has taken place in a gun which has demonstrated near match accuracy. I would score in the high 230s on a target face of 11mm at 25 yards from a sandbag and a score of 70% hit rate on a bench-rest target of 6mm at 25 yards while using a sandbag.

Look at the well grouped shots on linked target face one and then the rest. I see no engineering rationale for the previously successful pellets producing such wild variations. I am more than willing to learn and would be delighted to fill the numerous gaps in my engineering and shooting knowledge. I will of course be happy to try something that I have not already tried. thank you for your suggestions.

https://www.dropbox.com/sh/hxyps7ma7...th61b3PDa?dl=0

[old goat]

Like yourself had the same problem with my previously accurate HW100 went through the list of barrel cleaning and all the checks you have tried without any improvement, about to give up when a club member suggested I try a different batch of the JSB Exacts I had been using,problem solved,the Exacts i had been using differed vastly in size and length from my previous batches,i have always found my HW100 barrel to be pellet fussy

[gingernut]

I’m not trashing R10s.
I use them in my match pistols and rifle.
At 10 yards.

At 25 yds a bit of wind will send them all over the place.

[zephyr]

Hello Jeff,

I too would be flummoxed after having gone through the checks you have.

Are you still using the same tin of R10s? or a different tin?
Has the grouping also suffered with the other pellets you said you had previously been happy with?
As unpalatable as it may be, is there anything the shooter is doing that introduced the expansion of the groups?

Clearly something has changed from when you were able to get the fantastic group. You quoted Einstein (with which I totally agree), so to quote someone else "Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth.". You now have to think of the improbables, which will include everything not just the mechanics of the gun. The checklist will be vast, good luck.

ps different guns for different people - I sold my HW100 and kept my Mk4is.

[jepho]

Hello Jeff,

I too would be flummoxed after having gone through the checks you have.

Are you still using the same tin of R10s? or a different tin?
Has the grouping also suffered with the other pellets you said you had previously been happy with?
As unpalatable as it may be, is there anything the shooter is doing that introduced the expansion of the groups?

Clearly something has changed from when you were able to get the fantastic group. You quoted Einstein (with which I totally agree), so to quote someone else "Once you eliminate the impossible, whatever remains, no matter how improbable, must be the truth.". You now have to think of the improbables, which will include everything not just the mechanics of the gun. The checklist will be vast, good luck.

ps different guns for different people - I sold my HW100 and kept my Mk4is.

Hi zephyr. 👋🏻
Thank you for your thoughts and your helpful input.

I have taken pellets from 7 different tins of R10s. I have added JSB exacts, Bisley Magnums, Bisley Practice, H&N FTTs and RWS Super Fields. The random scattering of shots has occurred with every pellet from every tin.

I am not drunk or drugged when shooting every week. I can and have shot freehand, standing and sitting plus I have used a sandbag and a bench-rest and the results are similar across all modes of shooting and all pellets. I don't believe that my technique has changed and suddenly become inaccurate. At the weekend , I shot a group of five from 16metres. The group was less than the size of a small fingernail and it was produced with a fairly old Walther LGR. At 25 yards, I shot a group about the size of a 5p piece with open sights and an HW77.

Hopefully my leaving the gun with an expert gunsmith will throw some light on the issue. More anon once I know what has changed.

[jepho]

I’m not trashing R10s.
I use them in my match pistols and rifle.
At 10 yards.

At 25 yds a bit of wind will send them all over the place.

Thank you. My mistake and I am sorry you got caught up in what I saw as another complaint against a perfectly usable pellet. 🤭
FWIW, all of my recent shooting has been done indoors so I don't have the wind to contend with. I am currently waiting for the completion of a 70 yard outdoor range.

[jepho]

Like yourself had the same problem with my previously accurate HW100 went through the list of barrel cleaning and all the checks you have tried without any improvement, about to give up when a club member suggested I try a different batch of the JSB Exacts I had been using,problem solved,the Exacts i had been using differed vastly in size and length from my previous batches,i have always found my HW100 barrel to be pellet fussy

Thank you for your time and the valuable response. In engineering terms, I don't understand pellet fussy as a description. If that means that Weihrauch makes a barrel that is set to handle different pellet configurations in different ways, then the parameters used to manufacture the barrel are known and the best pellet for that specific configuration of the barrel is also a known. Knowing how German engineering tends to handles issues, I would expect Weihrauch to understand barrel variation and the implications of each standard deviation barrel from the expected norm.

Hitherto, all of my pellet choices have demonstrated and underlined the accuracy of the HW100... so much so that my son called it "cheating", every time I used the gun; regardless of the pellets I used. For now, I have left the gun with a highly recommended gunsmith and will report back to the thread once I know what the problem is and how it was solved. As a scientist and an engineer, I want to learn about the explanations that make sense to me. Feelings and beliefs have no place in my world and all things are explicable.

Since the problem began, I have used just about every high quality pellet available and still I am not seeing any improvement. This fact alone suggests that pellet choice is not responsible for creating the problem. For the sake of furthering the debate, if we accept the assumption that all pellets are different, then I should have seen an improvement representing consistency, even if the group was orange sized when I changed my pellets. No such improvement in consistency has been seen. All pellets produce the shotgun patterns shown.

[angrybear]

Thank you for your time and the valuable response. In engineering terms, I don't understand pellet fussy as a description. If that means that Weihrauch makes a barrel that is set to handle different pellet configurations in different ways, then the parameters used to manufacture the barrel are known and the best pellet for that specific configuration of the barrel is also a known. Knowing how German engineering tends to handles issues, I would expect Weihrauch to understand barrel variation and the implications of each standard deviation barrel from the expected norm.

Hitherto, all of my pellet choices have demonstrated and underlined the accuracy of the HW100... so much so that my son called it "cheating", every time I used the gun; regardless of the pellets I used. For now, I have left the gun with a highly recommended gunsmith and will report back to the thread once I know what the problem is and how it was solved. As a scientist and an engineer, I want to learn about the explanations that make sense to me. Feelings and beliefs have no place in my world and all things are explicable.

Since the problem began, I have used just about every high quality pellet available and still I am not seeing any improvement. This fact alone suggests that pellet choice is not responsible for creating the problem. For the sake of furthering the debate, if we accept the assumption that all pellets are different, then I should have seen an improvement representing consistency, even if the group was orange sized when I changed my pellets. No such improvement in consistency has been seen. All pellets produce the shotgun patterns shown.

It means just what it says, the barrel is extremely fussy about what it will shoot accurately, in an extreme case it can mean that with the same make & size pellet it will be super accurate with pellets from one batch or die press, but pellets from a different batch or die press are hopeless.
My .25 rapid will single hole with JSB like your pic1, but with any other pellet is like your pics 2 & 4, thankfully it's not batch fussy within JSB.

Are your pellets the same batch now as when it shot that single hole ??

[jepho]

It means just what it says, the barrel is extremely fussy about what it will shoot accurately, in an extreme case it can mean that with the same make & size pellet it will be super accurate with pellets from one batch or die press, but pellets from a different batch or die press are hopeless.
My .25 rapid will single hole with JSB like your pic1, but with any other pellet is like your pics 2 & 4, thankfully it's not batch fussy within JSB.

Are your pellets the same batch now as when it shot that single hole ??

Thank you for your response. The pellets are now from a different batch, which shot well before they did not.

The fussy barrel notion still has me confused. My understanding is that the barrel is a convenient piece of tempered metal which is drilled to a convenient size and it may or may not be rifled. It will be a tube of known hardness and dimensions and finished to a known surface smoothness. It will not tend to flex and machining it should produce a similar resonant frequency for 100% of the samples tested. If the variation in the finished size of the drilled hole is uncontrolled, the barrel will be as near to unfit for purpose as it is possible to make. I suspect that the tolerance of the drilled hole is very tight for the nominal calibre.

In my early days, I would have to make products (without laser guidance or cutting) using ordinary machine tools. I worked to plus two ten thousandths of an inch and minus nothing. That was high precision back then. Today, the highest precision can be obtained with CNC and lasers or water jets. I assume that high precision work is far better today than it was when I first planned and cut a cam or produced a gear wheel or screw thread.

Given my assumptions (if correct) about barrel production for manufacturers such as Weihrauch, Walther, Feinwerkbau and Anschütz, I don't understand how an inanimate piece of metal (with a hole in the barrel that is nominally .177) can be fussy about which pellets it can use. It is also notable that we tend to find German engineering to be of the best quality. My HW100 appears to like all of the pellets with which it has been fed and I have an expectation that this would be the normal use case. Likewise; my Air Arms Alfa Pro J pistol for 10 metre work, does not appear to mind which pellets it is fed with. I tend to keep using the R10s but have had similar results with H&N FTTs, Bisley Practice and JSB Exacts. In absolute quality terms, I find the R10s excellent for QA. Using them means my lazy self has one less job to do.