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QB78 Family Workshop Manual – New airgun book!

by B.B. Pelletier

I have a real treat for everyone! A new book about airguns has just been published, and it’s one I know you’re going to enjoy. It’s the QB78 Family Workshop Manual by Stephen Archer, and it’s all about the QB78 CO2 rifle. When I say “all about,” I’m not exaggerating!

Everything you ever wanted to know about the QB78!

What’s a QB78?
The QB78 is a modern version of Crosman’s famous 160/167 air rifle. I wrote about it on November 7, 2006. Many of you already know what a fine air rifle it is. For those who don’t, some research is in order. Before the 78 was available, people were paying up to $250 to get a Crosman 160, because the supply is limited and the rifle has some great features. The QB78 is essentially the 160 made for everyone.

I learned!
In just the first scan of this book, I learned that my velocity recollections for the 78 are incorrect. I had the .177 down for 700+ and the .22 for 600 f.p.s. But the author tested many rifles and presents a table of observed velocities that are quite a bit lower. He also shows the factory spec for both calibers and where actual rifles he has tested fall against it! You usually can’t buy that kind of data. The rifles I tested must have been tuned before they were sent to me.

But the best part of this book are the technical details about the rifle. It starts by assembling a tool kit and takes you through complete disassembly of the rifle, adjustments, repairs and troubleshooting. Determining what to fix by where the gas escapes the gun is very helpful info, and that’s just one of the tidbits I picked up in this book. The instructions are specific and complete, and they take you all the way down to every part of the gun. Even the complete valve disassembly is described in detail. Assembly instructions are far more comprehensive than the usual “do everything in reverse.” You are shown special assembly tips and even told how and what to lubricate as you assemble.

Performance charts
This book is filled with charts of caliber-specific velocity and accuracy gathered from hundreds of individual tests. For example, Archer charts the power curve of both calibers as it relates to the ambient temperature. I had a question this week about how airguns do in heat; this book shows how the QB78 is affected, degree by degree. You might be surprised to know there is a power downturn as the temperature gets up over 96 degrees F, so shooters in Las Vegas aren’t always in the ideal circumstances we sometimes think they are.

Another reader asked several months ago if I would address customizing airguns with various accessories. This book gets into that, telling you how to change the stock, installing a custom bolt handle, fitting a sling, refinishing a wood stock and bedding the action, and converting the rifle from 12-gram cartridges to bulk-fill.

The book is filled with detailed photos and line drawings. The author has pictured aspects of the technical work that are difficult to convey with words, and there are many assembly drawings of parts, such as the valves. There’s also a numbered parts list that translates Crosman 160 parts numbers to QB numbers where the parts interchange. Where they don’t interchange, you are told what doesn’t work (and sometimes why).

The 88-page book is available from the author. Contact him at www.archerairguns.com. The price is $24.95 and $5 shipping to any address in the 50 States and $10 to the rest of the world.

31 thoughts on “QB78 Family Workshop Manual – New airgun book!”

  1. It almost makes you want to buy the gun and the manual just for the fun of tearing it down and rebuilding it! Also I learned that you can breed airguns if you can determine how they do in heat! (I had to say that!) 😉

  2. Yes, there are ways (plural) to convert CO2 guns to air. Dennis Quackenbush was the first to do it with his .375 Brigand. On air it got fewer shots (4, as opposed to 10-12) at higher velocity (800 f.p.s., compared to 625). All he did was fill the reservoir with air to the same pressure as CO2.

    The Air Arms S200 was actually a CO2 target rifle that some American field target shooters started converting to run on air. In that case…

    What the heck – Monday’s blog!



  3. BB,

    I’ve been outta town and just read your response of a couple days ago.

    yeah after reading about the “one handed” you mentioned i can see I missunderstood. the pump sounds good.

    tell me more about the $300 PCP.

    I will look up your review on the AR6 rifle.


  4. $300 PCP,

    There’s nothing much to tell except the gun is being delevoped. Don’t know whether it will work and how well, if it does. The question was more along the line of, “Would that be a price that doesn’t break the bank?”


  5. hello,B.B. Pelletier,
    i am a airgun fans ,and now,i am going to make a gun which structure is more like talon by myself.and i have to get a pump,and some information about that,could you tell me something about that? or you have a MSN?we can disscuss about this and some other things about airguns.
    would you please give me you MSN,if you have not,E-mail is ok.
    thank you.

    and my email is :wb_yeibon@163.com
    also was the MSN.

    best wishes!

  6. Hi,

    I understand you have rather a great wealth of knowledge on matters of CO2 guns. I am from the U.K., and I reside in London, England. I am somewhat interested in purchasing the CO2 Baikal Makarov MP654K or CO2 Walther PPK(/S). Now, I understand the Mak is slightly more powerful, but http://www.007-qbranch.com offer a replacement threaded barrel for the PPK, which can therefore fit a variety of real silencers or most importantly, a dummy silencer which is essentially an extended barrel. I imagine therefore this would increase the power of the gun and perhaps make is more worthwhile than the Mak which I must say I prefer due to it’s interesting history and ‘real’ gun components. If you could respond, I would very much appreciate it.


    J. Stevenson

  7. J. Stevenson,

    I own both a Mak and several PPK/Ss, and I would say get the Mak first. It is the real thing! I also have a Mak firearm, and the two guns are very similar. The biggest differences stem from the fact that the firearm is Bulgarian while the PP gun is Russian.

    You will love the gun.

    The PPK/S is also very realistic. I have a PPK/S firearm that I bought after getting the BB gun and those two are also very similar.

    So maybe you need both.


  8. Ah but so hard to choose! A small problem is lead balls are hard to get hold of round my way, and don’t want to damage the rifling if I get the Mak. Hmm… Do you think a dummy silencer would increase muzzle velocity? As it essentially an extended barrel.

    J. Stevenson. (again)

  9. J. Stevenson,

    A longer barrel will increase velocity. A separate device screwed on the end of the barrel does nothing by itself. If the joint between the barrel and the silencer tube were perfectly tight and the silencer barrel were the indentical size as the bore, perhaps a gain would be possible, but that’s a lot of “ifs.”


  10. B.B.,

    Thanks very much for helping me out – I really appreciate it. I think I will go with the Makarov then. Perhaps later I will get the PPK. It’s difficult to find a suitable candidate for my first CO2, because so many have different pros and cons that cancel each other out.

    Many thanks again B.B.

    J. Stevenson

    (don’t ask why I make my name so formal – I just think it looks cool!)

  11. B.B,

    Is it particularly difficult to thread a Makarov barrel to 1/2″ in order to fit say a Logun suppressor. I would like to be able to silence the Mak but the barrel is a bit of bastard to remove I hear…

    Mr Stevenson

  12. Ah yes adaptors… I wonder if it has been done before. I’m just waiting for a transfer to paypal then will order from airshooter.co.uk. Do you know of anyone who has successfully fitted a sound moderator to a Makarov?

    Mr S.

  13. Hmm, now I am thinking some sort of push on silencer could be easier. It’s all pie in the sky though, I haven’t actually ordered the bloody thing yet!

    Sorry to use your posting as my thinking place…

    Mr S.

  14. i was just wondering about these co2 blow back pistols that are out.ie cp99compact,pro77.i bought a crossman 357 with 6inch barrel for my wife to shoot in my garage range.
    she likes to shoot but says the pistols does not have enough power and thought the blowback style would have the kick she wants but still be in the .177 caliber for our basement plinking

  15. BB,
    I’m thinking extremes. I want to bore out the barrel on my [already]modified 22SG to .25 caliber. I remember you mentioned tolerences for pellet rifles than their firearm counterparts, but (assuming firearm bore is a few thousandths bigger than pellet), would some pellets be big enough to take up that slack? I assume I would want an AIR gunsmith rather than firearm anyway. Either way, maybe let me know what kind of problems you forsee. (I’m only doing this because I’ve nothing left to lose on my SG, and the price and type of .25’s available leave me limited). JP

  16. JP,

    If I understand you, you will be going for a smoothbore in .25 cal? You need a barrel drill with a special pilot so the bit doesn’t wander. Then a barrel reamer to finish the job.

    On your .22 questions, no diabolo pellets are made anywhere close to large enough for a .22 firearm bore. The difference is over 5 thousandths. And air rifle .22 bore is no larger than 0.218″ and a firearm barrel is no smaller than 0.223″, though there have been a few 0.2225″ barrel made in the past.

    Why not just replace the barrel of your .22 SG? A Daisy is not a rifle to gunsmith. It isn’t made of materials that can stand up to a lot of modification.


  17. I’m just tinkering because I like to, and also I’m not yet ready for the price/type of what .25’s are available. I’m going for a rifled .25 if possible, and the barrel doesn’t come loose from the valve body from what I see. Still, I managed to get a parts breakdown and order form from Daisy, so I may just re-build my SG if it doesn’t work. I’ve had fun with a .177 plinker I’ve acquired, but I do miss the knockdown a .22 can give to a pop can. JP

  18. Hey pelletier,I have a problem with the career 3 707. First off is the fact that not much is said about this rifle.Not too many reviews that I can read about it.Needless to say, I very foolishly dicided to buy one from pyramid about 7 months ago.Since there is an iguana problem here in Puerto Rico I bought mine in .22 cal.Much to my dismay the first thing that happened was that it did not come with the universal pellet adjuster that supposedly came built in it.O.K. I said,I”ll just use it single fire, after all I was used to the springer which shoot one at a time anyway.Then the lever broke and I had to send it to craig at pyramid to have it fixed.103.00 bucks later I recieve my gun back and although the pellet adjustment had been installed,I noticed that now the skirts get stuck on the breech where the pellet port picks up the pellet!What the@%$&*is wrong with this rifle! Am I the only guy with this lemon rifle?All defects aside,I still think that the career coul be one of the best rifles money can buy.Help me out guy if you can.Miguel Diaz.

  19. Miguel,

    Maybe not a lot is written about the 707 today, but when I wrote The Airgun Letter people used to complain that was all I wrote about.

    You need to adjust the pellet feed mechanism to keep from getting pellet skirts caught. And if the adjustment is out as far as it will go, your rifle won’t shoow that type of pellet.

    Career 707s like Crosman Premiers.


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