Author Topic: QB79 Ninja - The $200 PCP (Read 127757 times))

rsterne · « **Reply #80 on:** August 06, 2013, 09:05:01 PM »

Froggy.... Here is a thread that talks about the difference that volume makes in a QB78 or QB79.... http://www.gatewaytoairguns.org/GTA/index.php?topic=21681

On 1500 psi and with a valve where the front end was slotted (same valve in both guns), the difference was about 5 FPE.... What happens is that the AVERAGE pressure at the valve seat increases with the larger plenum, so the gun shoots as if you cranked up the regulator setpoint.... The efficiency also increases with the larger plenum, so it's a win-win situation....

Bob

Captain Bravo · « **Reply #81 on:** August 16, 2013, 04:57:39 PM »

I have read other places that a "...Paintball Tank Adapter for QB79" might be required for a 2" tank. Did you need one for the Ninja hpa setup, or was there enough clearance?

rsterne · « **Reply #82 on:** August 16, 2013, 06:02:58 PM »

Modern paintball CO2 tanks are 2.06" diameter and need an adapter to clear the barrel.... The Ninja tanks are 1.998" OD and clear the barrel just fine....

Bob

Captain Bravo · « **Reply #83 on:** August 16, 2013, 07:32:06 PM »

That is what I was hoping. Thanks Bob

rsterne · « **Reply #84 on:** August 23, 2013, 10:35:20 PM »

I finally had a chance to do some testing outdoors today, so I tested all the pellets scoring "green" in the last tests indoors that I expected to have a decent BC at 25 yards.... I measured the average velocity at the muzzle and at 25 yards, for 5 shots with each pellet, and then used ChairGun3 to calculate the Ballistics Coefficient.... Here are the results....

The groups were sorted as usual, with any group you could cover with a Dime scoring green, any group you couldn't cover with a quarter scoring red, and in between no colour code.... I was surprised that all the JSBs were the only pellets that produced sub-dime sized groups.... and the best of those was the 15.9 gr. Exact Jumbo.... When you look at the JSB Exacts, the heavier the pellet the better the BC, as expected, and this results in a lot more FPE at 25 yards.... However, with the combinaton of good velocity and high BC, plus superb accuracy, I chose the 15.9 gr. as the pellet to use.... After sighting the rifle in 1/4" high at 25 yards, here is a typical 5-shot group....

The small squares are 0.1", and the black squares are 0.4", so the C-T-C size of that group is less than 0.25".... I can get 70 shots per fill at 25 FPE, and basically it just keeps dumping them in a ragged hole at 25 yards.... I think we can call this project an unqualified success, and this rifle has earned a place on my "wall of keepers"....

Bob

Mebits · « **Reply #85 on:** August 24, 2013, 07:50:50 PM »

Nice. I love mine, I can tell you.

Rdsail · « **Reply #86 on:** October 17, 2013, 08:13:03 AM »

Quote from: rsterne on August 05, 2013, 07:18:58 PM

I finished and installed the stock today....

It's a Richard's Microfit Wildcat Thumbhome in Select Grade Black Walnut with Ebony Grip Cap.... beautiful figuring in the grain....

I had to shorten the forearm and inlet it for the tank block and regulator.... The finish is 7 coats of Watco Danish Oil, each coat wet sanded, ending with a white Scothbrite pad of 1200 grit equivalent and then a coat of Dark Minwax.... The scope is a Leapers 3-9 x 32 AO with Sunshade.... The gun weighs 8 lb. 7 oz. as shown.... The Air Stripper is from a Hatsan PCP, I threaded the barrel 1/2"-20 NF to accept it....

It's no longer a $200 PCP, however....

Bob

bob, As always, amazing work. I disappointed that I found this post so late. There are a lot of parallels with my bottled disco and I was building it around the same time.

I looked at this pictures and they look very similar to my disco. One mod that I made that many people comment on is how if fill the gap between the stock and bottle and the barrel. I wen to the office supply store. Bought a black blastic textured folder. I got the heavy plastic. The light plastic does not work as well. then cut out a rectangle. then the openings for the gauge and rounded the two corner by the bottle. It took about 5 minutes to do and it looks it was molded in place.

Just a thought.

bradyman1 · « **Reply #87 on:** November 18, 2013, 10:42:15 PM »

What a fantastic job. Awesome project!

unclejack · « **Reply #88 on:** November 20, 2013, 02:32:20 PM »

I found the larger tank type modification on QB79. In order to install a larger tank, the stock part has been modified as bullpup.

Gertrude · « **Reply #89 on:** November 20, 2013, 03:45:49 PM »

Quote from: unclejack on November 20, 2013, 02:32:20 PM

I found the larger tank type modification on QB79. In order to install a larger tank, the stock part has been modified as bullpup.

Ok,... now THAT just about takes it as far as it could go! I have been wanting a MM tuned QB79 for quite some time here... And THAT has just pushed me over the edge !
WOW !
We need more details on that stock and that build ! That is SWEET !

MIKE ! ! !
YOU NEED TO GET SUMMADEEZ STOCKS ! or find out where they can be had !
IMMAGUNNA have to Figgerout how I can get ONE-A-DEM !

RMM · « **Reply #90 on:** November 21, 2013, 12:25:45 PM »

Quote from: tri-5-ron on November 20, 2013, 03:45:49 PM

Ok,... now THAT just about takes it as far as it could go! I have been wanting a MM tuned QB79 for quite some time here... And THAT has just pushed me over the edge !
WOW !
We need more details on that stock and that build ! That is SWEET !

MIKE ! ! !
YOU NEED TO GET SUMMADEEZ STOCKS ! or find out where they can be had !
IMMAGUNNA have to Figgerout how I can get ONE-A-DEM !

Click on the link at the bottom of unclejack's pics and your bullpup fantasies will be fulfilled.

You will have to run the page through a translator but it's well worth the visit..

chuckinohio · « **Reply #91 on:** November 21, 2013, 01:41:19 PM »

Any thoughts on using a 17ci Rap4 tank to get a higher shot count before refilling?

http://www.rap4.com/store/paintball/p/015194/hpa-17ci-3000psi-compressed-air-tank-empty

Its specs say that it is 1.938 in diameter, and fitted with the Ninja SHP regulator, it ought to do the trick as well correct?

rsterne · « **Reply #92 on:** November 21, 2013, 04:33:12 PM »

Yep, slightly more muzzle heavy.... and by the time you buy the tanks and regulators separately, will likely cost more.... Your shot count, similarly tuned, should increase by 17/13 = 30%.... That would take my gun from 80 shots to about 105 shots per fill.... Is that worth it, only you can decide....

Bob

chuckinohio · « **Reply #93 on:** November 21, 2013, 07:24:15 PM »

The 13ci set up from your OP is definitely the way to go as far as cost and ease of procurement.
I suppose that if one just had to have the extra 30% increase in volume, the extra $100 bones for a 17ci tank is a soft enough blow.

Thanks for ALL of the great info in this thread, it's got me thinking that PCP isn't an expensive proposition after all.

Geoff · « **Reply #94 on:** November 21, 2013, 07:47:03 PM »

tagged to check back and read this thread.

one think i will look for is ... this is ~200$ .. a used disco is ~200$ .. either one have a leg up on the other ? if this was mentioned, apologies as i will be reading the thread tomorrow.

nervoustrigger · « **Reply #95 on:** November 21, 2013, 09:32:56 PM »

If you can do the work to the QB to bring up the power level, you'll have:

1. more shots per fill (4x as many?)
2. consistent shots (the benefits of regulated air pressure)
3. better trigger

I realize that first "if" is a big one for a lot of folks but for a tinkerer, the QB platform is a dream.

Rdsail · « **Reply #96 on:** November 21, 2013, 09:39:50 PM »

I get more than that on my disco. It just cost more and the platform in a better IMO. endless mods. I still thinking of addend a bolt less probe and longer barrel

woogie_man · « **Reply #97 on:** November 21, 2013, 09:49:28 PM »

Question about the tank drop part.....are you able to butt that right up to the valve? Our what amount of space would be needed?

Ribbonstone · « **Reply #98 on:** November 21, 2013, 10:47:24 PM »

For power, the more space between valve and tank, the better.

woogie_man · « **Reply #99 on:** November 22, 2013, 03:57:06 AM »

Ok....

Still trying to decide if I want to go this route or use the 2240 as a base for a compact little build.

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QB79 Ninja - The $200 PCP

Author Topic: QB79 Ninja - The $200 PCP (Read 127757 times))