My 177cal QB78s comes in on Tue, what to expect velocity wise ?

[wll2506]

I have many QB's and all are .22 cal and most modified to HPA except one. This new synthetic stocked version is 177. I plan on using CPUM's as I have LOTS of them and they shoot well in my more powerful 177 cal guns..

What I'm looking for is a velocity in the 625-650 fps range. I don't want to go crazy doing all kinds of mods, I just want to put a scope on it and go out and shoot. The ONLY thing I may do is set it up for bulk Co2, but not sure ? Since the stock is a black synthetic, this gun will be a real user ;-  ) I don't even plan on putting on a moderator --- i want this gun to be pretty my down and dirt, if ya all know what i mean ;- )

Anyway, those of you that have this gun in 177 and shoot Co2 please give me your thoughts.

Thanks as always,

wll

[Earl]

My QB78s shoots JSB 8.44 at 622 fps, AA Falcon 7.33 at 653 fps, RWS 7.0 at 617 fps.
My QB78D shoots JSB 8.44 at 551 fps

[wll2506]

So I'm sitting around the house with nothing much to do except watch the news and raise my blood pressure - so I decide to sight in the QB78D in 22. 

I take it out to the backyard, set the target up at 17 yards and start shooting  ---- I was amazed, the trigger was extremely nice and I did nothing to it !!, the CPHP pellets are hitting one after another between a penny and a nickel size AT MOST !!

I just wanted to shoot a few shots, but the gun would not run out of gas !!!, and I just put in ONE CO2 as I did not want to turn this into an all day shooting event---- but it just about turned out to be ---- I got over 25 shots on ONE CO2 :-)  , and these were powerful shots !!!

It has been a few years since I played with the QB78 platform and to say I was impressed was an understatement --- no I did not chrono the 14.3gr CPHP,s. If my new QB78s in 177 shoots anything like this I will be extatic.

I thought I would be taking out my Talon CO2 gun or my Fusion 2 tomorrow ----- Well I'm taking this baby ---- one CO2 gives me plenty of shots for my outings, I can uncock the gun, the trigger is FAR, FAR superior to the Fusion 2 AND it is easy to load having an open breach. Also the lower CO2 just falls out when you want to dump the CO2,s, much, much better than the hassle I have everytime with the Fusion 2 .

The Fusion 2 is quieter and is just as accurate if not a little more so than the QB78. The Fusion 2 and the QB are two different animals for sure, BUT - BUT, the QB series has all kinds of additions and add ons and is very customizable - a big plus !!!

So, I put the QB78  is in it's case and I'm ready to head out tomorrow :-)

Till then,

wll

[Madd Hatter]

You're going hunting on Valentine's day? Brave man🤪

[soupyyy]

Mine is shooting the CPHP 7.9 at 80 degree on 9/20

667  662  663  660  661

Average 662.60
7.70 fpe

[Back_Roads]

 That sounds right about inline with mine Soupyyy ! I did also find good shot count with a single 12 gr.
Had to add a pic, I do not read GTA just for the articles

[wll2506]

Head out to my area and arrive at 7:15. Load up a CO2 and I'm shooting in the 450fps range and from there velocity quickly went down in the low 300's and then ran out. I load up another cartridge and I get a few shots and then out, all the time I'm feeling how cold the receiver section is and I seem to smell CO2. I load up an other cartridge and it leaks profusely from the cap "O" ring. Well that factory white "O" ring was ripped and torn and was totally coming apart ---- I head for home for a fix but stop by a little country store that was less than 10 minutes away and ask if the had "O" rings ---- they did, they had a pack that contained an assortment and three were 13/16" ---- just what I needed ---- to say these rings were cheap would be an understatement -- they just said they were made out of rubber - NICE :-)

I took the old "O" ring off, replaced it, loaded one CO2 and everything was fine. I'm using just one Co2 as I rarely take more than 15 shots on an outing unless I'm testing something. The velocity with CO2 will be the same with one CO2 as with two, it is I would get more shots with two and shots would probable be a bit more consistent.

Re-chronoed and out of 5 shots I was averaging 482fps with these 15.89gr pellets giving me a bit over 8fpe. Not a powerhouse, but OK for what I'm doing and happy that my zero was on at a lasered 25 yards :-)

It is 9:30 now and the sun is out and its 72 from where I'm shooting, it is 51° outside. The wind has started to pick up a bit so I may be out a here in a short while.

Before I take off I decided to shoot at a full fruit can at the 25 yard mark I was shooting. This was the 18th shot from a single CO2 --- it went completely through, showing me I definitely had the poop to pop Starlings and Pigeons from that range using just one Co2 and JSB Jumbos. I shot 25 shots and my pellet did not drop and was hitting where I shot, I shot 5 more shots and she was running out of poop, it took me quite a few empty shots to be able to start to loosen the cap. It took me a while before I could get the cap off, the cheap "O" ring had greatly expanded, as a matter of fact I put it between my lips and felt the "O" ring out gassing. After about an Hour it came back very close to it's original size ... I will be buying some good "O" rings ;- )

A pic of both sides of the can below, below that the QB78D as I shot her today. :-)





I'll be out again tomorrow, same time, same bat channel

wll

Side Bar --------------

Just ordered a bunch of "O" rings from "The "O"ring Store"

[wll2506]

Mine is shooting the CPHP 7.9 at 80 degree on 9/20

667  662  663  660  661

Average 662.60
7.70 fpe

Nice looking moderator on unit, very nice;-  )

wll

[wll2506]

 That sounds right about inline with mine Soupyyy ! I did also find good shot count with a single 12 gr.
Had to add a pic, I do not read GTA just for the articles

Your is 177 ? have you shot any heavy 177 cal pellets and whats your velocity ?

wll

[Back_Roads]

 That sounds right about inline with mine Soupyyy ! I did also find good shot count with a single 12 gr.
Had to add a pic, I do not read GTA just for the articles

Your is 177 ? have you shot any heavy 177 cal pellets and whats your velocity ?

wll

 I think all I have shot out of it is 10.x gr. CPHP When my basement or the outside gets into the 70's I can report back, them may try mods, if I'm not using enough CO@. I did have it valve lock from being too hot last summer, so I may need some hammer spring tweaking for sure.

[wll2506]

It is a beautiful morning out here in the boonies. The Sun's coming up along with the haze on the desert floor and the rain clouds up above -- it is beautiful.

I sit here with the QB78 at my side, loaded up with one Powerlet, shooting JSB Jumbos. I fired off about 4 shots at targets of opportunity --- rocks, dirt clods and such - she was right on. The o-ring that I used yesterday and I thought had gone down to it's original size did not, so I had to put a new one in. I am waiting on urethane "O" rings from the O Ring Store to come in this week.

The wind has just picked up in a hurry and it is a very cold wind along with the very cold 46°. For some reason today it seems alot colder than the temp says - I'm  sure it because the wind today is freezing cold !

For the things I want to shoot I feel very confident in this gun and I'm really waiting on the QB78s in 177 that will be here tomorrow. I will check her out thoroughly and put a 3x9 Optima scope that gets traded from one gun to another on her. I will put a new breach seal in her if I feel that it is a bottle neck, in my cases of extra airgun parts I found some 130-036 breach seals - one of them may well have a home in my new gun. I may also take the screen and felt washer out of the valve.

I would like to shoot in the 625fps area with CPUM if possible without a bunch of crazy mods.

If this gun is accurate and I can get some good speed, this could be a great gun for my small pesting "WANTS" ;-)   ---- It is inexpensive, it has a tough plastic stock, I can buy all kinds of upgrades and mod till my brains fall out - Perfect !
It is not as quiet out of the box as my Fusion 2 or designed to use a magazine, but thats OK.

Till tomorrow, God willing and the creek don't rise !

wll

[Rob M]

mine was shooting 755fps with 7.9 premiers .. few minor mods , mostly unblocking the obstrutions in the valve  gas path;. I dont think i even did any porting if i recall correctly.. It was summer time though

[wll2506]

mine was shooting 755fps with 7.9 premiers .. few minor mods , mostly unblocking the obstrutions in the valve  gas path;. I dont think i even did any porting if i recall correctly.. It was summer time though

"Obstructions in the valve" I assume that means you got rid of the felt  filter, the screen and maybe the sleeve that the spring and piercing piece fits in ?

wll

[Rob M]

mine was shooting 755fps with 7.9 premiers .. few minor mods , mostly unblocking the obstrutions in the valve  gas path;. I dont think i even did any porting if i recall correctly.. It was summer time though

"Obstructions in the valve" I assume that means you got rid of the felt  filter, the screen and maybe the sleeve that the spring and piercing piece fits in ?

wll

yes, i remember needing washers in various sizes.. this was 2 yrs ago when i modded it..

[wll2506]

My QB78s came in today, I put a scope on her and with a long BIG screwdriver I took out the silver end of the valve unit. I took out the felt in the front end, took out the black tube that surrounds the innards and I notched out the "O" ring in four places. Put the unit back together and HOPEFULLY got it in correctly as the piercing pin did not want to stay centered .... I'm hoping on my 4th try I got it right, I really did not want to take the gun apart, I wanted to do this fast and dirty. If I do have to take it apart I will install a Crosman 130-036 breech seal.  If I must take her apart this then turns into a bit of a project which I'm trying to avoid ;- )

I really don't want to take this gun apart. If I left her "AS IS" from the factory I don't think I would get around the 600+fps with CPUM pellets. The gun seems pretty tough and a good gun to bang around. Pic of QB78s below with 3-9 Optimus scope attached:



wll

[Nvreloader]

Will
Looking good, what do you think of the plastic stock, better than a wood 79 stock?

I need a slightly longer stock to fit me and that plastic stock looks good,
What is the LOP from the trigger to center of the recoil pad?

Thanks,
Don

[wll2506]

Will
Looking good, what do you think of the plastic stock, better than a wood 79 stock?

I need a slightly longer stock to fit me and that plastic stock looks good,
What is the LOP from the trigger to center of the recoil pad?

Thanks,
Don

Ctr of trigger to end ctr of recoil pad is 14-7/16"

The stock is very strong and is a real user, it is not really my cup of tea but it works, I like a traditional stock as for me it is more comfortable. But like I said it is very usable and tough !

wll

[Nvreloader]

Thanks Will

Now I got to find one..............LOL

Don

[wll2506]

Got home yesterday and tested the QB78s in .177 caliber. The work that I did would not puncture the bottom CO2 so I have to work on that today but it did puncture the top canister which gave me an average velocity of 582 fps with 10.5gr Crosman Premier Ultra Magnum pellets, the gun shot was very, very accurately, I was very happy.

The trigger I will work on today as it is a little long, it's not too heavy is just a little long for my liking, that will take about 2 seconds. I will try to be able to get the piercing pin working in the tube at the bottom, if not then I will take the gun apart and put in a breach seal while I have the gun apart ---- all in all I am very happy. I am getting a little over 8fpe right now as it stands, I really want to get around 9 plus foot pounds at the muzzle. I will disassemble AFTER I get the needed "O" rings from the "O" Ring Store so I do one takes part and do everything ! Even If I can't fix the Co2 thing, this gun is going to the field this weekend :-)

After shooting and playing around with this gun I get more impressed by the minute. The stock, even though not my cup of tea is built like a tank and should be great for the field, I'm very skittish of taking my wood stock guns out in the boonies. I MUST admit the more I shoot this stock the more I like it :-) I will take the Picatinny rail off and take the shiny finish off so it is flatter. Everything about this gun is tough and strong, this gun has a new synthetic stock, but the gun has "OLD SCHOOL" but upgraded china quality, if that makes sense. I took the front bottom Picatinny rail off, and no cheap self tapping wood screws -- Has machine screws, with nuts and a metal backing plate ---- nice, real nice :-)

The gun has enough poop for the type of game that all go after and is shooting flat enough to around 35 yd to be more than adequate for my needs I just want a little bit more energy that's all.

SIDE BAR ‐‐‐------------------------------------

I took the valve out today and tried to center it without taking the gun apart -- one of my guys at work made a long tool that fit in the valve and I may have centered it, used a telescoping inspection camera and could view the valve when inside the CO2 tube. This was a real pain, and if it is not centered, the gun will be disassembled, new O rings put in and go from there. I took out the popit to taper the back end, but it was done at the factory, and a very nice job. The Picatinny rail was sandblasted and painted flat black, it looks SOOO much better :-) I also adjusted the trigger, now it doesn't have as much travel ... very nice ;- )

I'm hoping that because the piercing pin could not move and the spring was pressing harder against the poppet and not a allowing it to move as freely as it normally would, I now may get more FPS, hopefully another 25+ fps ------- We will see.

Will post later after I get home :-)

wll

[AndyKunz]

You might find the thread on my Beeman 1085 (very similar to your new toy) helpful for the unpierced bottle problem.

https://www.gatewaytoairguns.org/GTA/index.php?topic=177197.new#new

I learned an awful lot about my gun doing that work, taking it apart and re-assembling again and again.  I'm happy with it now, though, especially with the extra power from the new transfer port.

Andy