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Alstone · Moderator & Site Supporter

Stevie!
Since you posted about SMK saying that the SMK XS78 fired at 800 fps for .177 and 600 fps for .22, I have had a good look round the web to see whats what, from what I can make out is that if a QB78 is advertised it usualy quotes 600fps for .177, where as an advert for SMK XS78 quotes 510-600 fps for a .22.

Also from what I can make out, the bits for these guns are imported and assembled over here, one firm doing this is SMK, who does QB I don't know, but this could make a diffrence in quality.

Anybody got any ideas on the subject, all imput will be gratefully recived.

Al

AirGunEric · Site Admin

I'm not sure how we can label this- but all the guns are made by "Industry Brand" and are "QB78"- with only the most recent version being called a "QB78 Deluxe". One is not a "QB78" and the other an "XS78"- the significant difference between SMK and XS is their respective sales territories- but the name of the gun is the same in either case.

That being said- there may be modifications to the guns depending on where they end up. Canadian guns, for example, are only imported by one company and this business from what I have been told (actually, it's a one-man operation) de-tunes them himself for their legal sale in Canada- meaning they don't exceed 500fps AND 4.2fpe of muzzle energy. He then will sell the parts that will return it to its previous state of tune for those people that have a Canadian firearms license and want to return it to its factory specifications. But he is neither Xisico or SMK- he is totally independent. Perhaps SMK in the UK has done this as well- but it seems unlikely if the newest versions are putting out more power than the older versions- all of which are still below the UK limit of 12fpe.

It seems more likely that the earlier versions of the gun put out less energy, otherwise- why have 4 different versions of the gun- if the only improvements were a slightly better sight and a metal barrel band? It doesn't seem very plausible it would take 4 versions over a number of years to only really change two features. It seems to me it would be more likely that other things also improved version to version, like maximum power output as an example.

Following this idea, I would also bet that if you went and purchased the newest version of the QB78 valve- you'd be closer to the higher output level that is advertised on more recent versions, with no other modifications.

AirGunEric · Site Admin

One other thing I forgot to mention: Those numbers that are advertised on the newer versions of the gun- they may only be "advertising" numbers- i.e. "Maximum velocity of 800fps". This trick is quite common in North America- for example a Crosman Quest 1000 is advertised as a 1000fps gun. Nobody can seem to determine what pellets this is with- because using a 7.9gr .177 pellet in one results in typical maximum velocities of 850fps. Many other guns have this sort of mis-leading ad copy- the keyword in the ads is "maximum..." where this number is often not achieved in reality- perhaps it has only been achieved on the design engineers desk.

Has anyone else actually chronographed their QB78 besides Al?

broommaster2000 · Moderator

With most airguns, power isn't that important. Most brands have quite powerfull rifles, but lack quality.

Alstone · Moderator & Site Supporter

Eric
What I was getting at was that SMK adverts all quote the same figures, and QB adverts all quote there own figures, and the two are different.

Broom
Yes I agree power isn't everything, and QB78 lack quality but they can be modified very easily.

Al

AirGunEric · Site Admin

Alstone · Moderator & Site Supporter

I did a search for QB-78 on UK web sites, then did a search for SMK XS78 also on UK sites, and the QB sites gave 600-620 fps for .177 and the SMK sites gave 510-600 for .22. and all the suppliers had the same blurp for there corrsponding perfix QB or SMK, so it appears that there are two different suppliers in the UK, and one of them makes the claim that there guns are assembled in the UK and incorperate british parts, whatever that means.

I'll get some suppliers web page ad's and post them so you can see what I mean.

I'm away for a couple of days now so I'll do it when I come back.

Al

AirGunEric · Site Admin

I think I see part of the issue now- there a sort of Apples-to-Oranges comparison being made.

For example- .22 pellets are a fair bit heavier than .177 pellets.

So, a common 7.9gr .177 pellet shooting 620fps is 6.745fpe of muzzle energy. A common 14.3gr .22 pellet propelled with 6.745fpe of muzzle energy would travel at 460fps.

Still the two outputs don't match the published specs very well- so perhaps you are correct and one of the two (I would suspect SMK) is modifying the guns, although I fail to understand why they would bother if the gun is already below 12fpe from the Chinese factory!

Perhaps the easy answer would be something to do with import laws and duties. For example, if one of the vendors is importing "parts" guns which are them modified/reassembled using "UK made" parts and labour- perhap they pay far less in levies. Is one of the two "lines" being sold a fair bit cheaper than the other? Even if one is not- perhaps the "manufacturer" is just keeping the extra $$$'s being saved and not passing it on to the customer. We had the same situation years ago in Cuba- the government there forced a doubling of the landed cost of Chinese-made televisions due to taxes, duties and "administrative" fees. So what did we do? We opened a television "factory" which put together the Chinese made sub-assemblies into working TVs and avoided all the additional duties/costs (of course we had to "partner" with the Cuban government to do it- so they still got a pile of the money generated from the products for virtually no effort other than their position).