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QB78 & QB79 Basic Valve Tune Power Mod (Part 1)


QB 78 and Crosman Valve Piercing pin Balancer

ok guys this is mod for the qb-78 and others that have the same valve including the crosman 160 167 etc.

QB78 Deluxe Modded - From Classic to Tactical

Proceso de transformación de un rifle de CO2, un rifle chino marca QB78 Deluxe.

El rifle lo transformamos de su look clásico a una versión táctica tipo AR.


- Se mejoró el flujo de aire en la válvula.
- Se aumentó el diámetro del puerto de transferencia, desde la válvula hasta el cañón.
- Se mejoró la corona del cañón.
- Se pulieron las piezas internas.
- Se reemplazaron todos los sellos y o-rings internos.
- Modificación del cerrojo para incrementar el flujo de aire.

Piezas adicionales.

- Culata táctica tipo AR.
- Culata delantera personalizada, de nogal.
- Silenciador de aluminio con bafles.
- Mira telescópica 3-9x40, retícula 30/30.

Tech Force 78 Trigger and Trigger adjustment from The "Airgun" Guru

Information on how to adjust the trigger of the Tech Force 78 and 79 as well as how to take the gun out of the stock.

SMK QB XS 78 79 Tuning

SMK QB XS 78 79 Tuning by TR Robb Airgun Specialist

qb79 on 1300psi hpa

A fuzzy video of a qb79 on 1300psi hpa in 177

qb78 trigger mod


Smk qb78 internal Polish

Qb78 xs78 internal part Polish! More to follow, sub, like, comment...

Tech Force 78 PCP Conversion Part 1

Information on how to convert your Tech Force 78, QB78 into a PCP rifle with the conversion kit sold by Compasseco Airguns.

To order the conversion kit:

QB78 - 12 ft/lbs rifle - info, shot groups, chrony results

video from years back, benefits of this rifle 1.) low cost 2.) parts available for everything on rifle 3.) accuracy 4.) all metal and wood 5.) can customize or do a project 6.) excellent trigger about 2 lbs 1 oz 7.) a good training rifle for kids 8.) no recoil 9.) can handle even the heaviest .177 pellet like the H/N 21 grain pile driver. for energy tests a 21 grain pile driver pellet does 510 fps at 12.13 ft/lbs, since this pellet has the highest ballistic coefficient of the .177 pellets it will not lose its velocity as fast as other pellets, this is due to the boat tail part of the pellet, so the 21 grain pile driver is more of a air bullet then it is a pellet. 10.34 grain air arms pellets will do 647 at 9.61 ft/lbs, 4.0 grain Crosman SSP pellets will do 821 fps at 5.99 ft/lbs, all of these results are with the XP bolt probe kit wich gives rifle a 100 fps boost, so just stock you subtract about 100 fps for these velocities, if you dont mind lower velocities its best to leave it stock, the best deal for this rifle is the all black version (not as pretty) but a little cheaper wich is why i would go deluxe type that has the (pretty look) for this rifle if doing bench rest accuracy testing, dont count the first few shots, allow barrel to foul a little so pellets group better, this is why its common to see people in 10m competition shooting 5 sets of 5 to validate accuracy, if you clean barrel or switch pellets alway run a few through the barrel for practice first, once you find your favorite pellet do a full cycle bore mapping this test you start on a clean barrel and fire all the shots at only one black dot per pellet ( 1/2 or 1/4 inch at 15 yards) never change aim point or adjust scope, always adjust scope to hit center before test, that way you can see the drop of each and every pellet and can even make a graph to display, this valuable data will be a guide to show what drop to expect and about at what shot number it starts at, so with a mill dot scope you can figure this in, CO2 rifles are a big challenge but its good to have a challenge learning drop and mill dots and different ranges, soon you will know your favorite pellet so well you wont need charts as much, also be shure on shooting event to mark down temperature, if you go out side allow rifle to warm to out side temp before shooting, so that way your readings wont be off so much, for every change in temp you will notice shot placement difference, keeping a zero with your scope doesnt always apply when changes to temp, CO2 pressure and other variables, so while shooting up to 50 shots you may have to adjust scope a little or even better go off a mill dot scope, for example my shooting session of 50 shots indoor started with a zero on a 1/4 inch black dot, by the time i got to 50 shots the point of impact moved down 1/4 inch. during shooting time its important for CO2 to have recovery time, wait a set amount of time in between shots, for me i was doing about 30 seconds in between shots, that way recovery time was equal, it may recover much quicker then that time but doesnt hurt to time each shot, this is needed anyway so you can get steady and hold breath a bit, on a 24x power scope you can see your heartbeat move cross hair about 1/16 of an inch even at 15 yards and for some maybe be more or less, but even your heart beat moves your impact even if breath is held, important also if not on a cement shooting bench that you table is allowed time to stop vibration, to test your table take a laser and set it on table so that it point to a piece of paper 15 yards away or what ever distance you want, them look at paper, you will see laser move on paper even though you could not see table move, its moving but we just dont see it, this is why some out door ranges and indoor have good solid shooting benches fixed to the ground, for accuracy testing a solid foundation is most important, you can see this is the scope sometimes but always get comfortable as possible and a good shooting foundation, because a CO2 rifle velocity gradually gets lower it is a good challenge compared to constant velocity rifles, it will test you at mill dot skills and scope adjustments, but that is good for the shooter as you learn how to make adjustments for point of impact along with finding the best pellet for your distance. alway be picky with pellets and have at least a dozen kinds so you dont miss that magic pellet for your rifles


500 fps advertised beeman air rifle from 79 to 129 price. 22 and .177 caliber

qb78 .22 modded

after a full internal mod i got the qb78d up to 14 ftlb on stock parts with modding. more to come!

QB Tuning

Další pokračování pokročilejšího tuningu QB-78.


Crosman 2240 valve pinning part 2 by Peas Productions

Second part with regards to 22xx valve pinning

Beeman QB79 .177 HPA Airgun

H&N Barracuda Match 10.65gr 4.52mm

Beeman QB 78s Barrel Shorten and Recrown, CO2 Pellet Gun Part 1

Hopefully this is of some help to somebody out there, great little gun for the money, I'm very happy with it. To crown the barrel I actually used a countersinking bit and a REALLY quick tap on the drill trigger was plenty.

Wiatrówka QB 78, tuning zaworu strzałowego (tuning valve)

Tuning zaworu strzałowego w wiatrówce QB 78. Wszelkie pytania na maila:

QB78D Ventil

QB 78 QB 79 And 4 Crosman 38's

the qb is a really cool gun very accurate and very close to the 500 fps mark as well, other then haveing crap valve and cap orings and crapy stem seal and transfer port once you work out these minor cheap to fix guns they are top notch, the crosman 38s are also very good guns as well .

Smk78/Qb78 -3d printed multishot magazine (15rd)

Smk 78/79 - qb 78/79 - multishot magazine.



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