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rsterne · Moderator

My .22 cal Discovery arrived today.... Rhonda at SSSO picked me out a dandy.... nice figuring on a dark walnut stock.... Cool

I shot 5 strings with various pellets starting at 2000 psi (guess what, the guage on the Disco agrees with the guage on the pump!).... The square black dots show how the pressure falls with each shot.... It only drops ~100 psi in the first 5 shots.... by shot 15 it's down to ~1600.... after that it loses 200 psi every 5 shots....

There are some interesting trends to note.... First of all, I quit shooting with each pellet when the velocity dropped below 90% of the maximum for that pellet.... You can see how much flatter the shot strings are with the heavier pellets.... I weighed 100 of each pellet to get the actual weights....Here is the summary:

Shots above 90%, 96%, and 98% of maximum velocity:

RWS Hobby 11.9 gr: 25, 20, 16
JSB Express 14.3 gr: 29, 24, 18
JSB Exact 15.9 gr: 30, 25, 18
Beeman Crow Magnum 18.0 gr: 29, 25, 17
Beeman Kodiak 21.6 gr: 32, 27, 23

Average Velocity, Energy, and Total Energy (over the 96%+ shots):

Hobby: 890 fps, 21.0 FPE, 419 FPE over 20 shots
Express: 827 fps, 21.7 FPE, 522 FPE over 24 shots
Exact: 797 fps, 22.4 FPE, 561 FPE over 25 shots
Crow Mag: 754 fps, 22.8 FPE, 569 FPE over 25 shots
Kodiak: 701 fps, 23.6 FPE, 638 FPE over 27 shots

My Conclusions (YMMV):

The Disco is capable of it's advertised 900 fps with Hobbies.... but they burn up air pretty quickly.... Shocked

With 14.3 gr. pellets, it is over 800 fps for 24 shots, peaking at 838 fps....
The Exacts look like an excellent choice for the Disco.... flat shot string, over 800 fps from 1400 psi to 1900 psi.... Cool

The Crow Magnums look a bit erratic in velocity in my gun.... YMMV....
The Kodiaks have the most consistent velocity, over 700 fps from 1400 psi to 1900 psi.... but a bit slow for my taste.... Neutral

The lightest pellets peak in velocity at about 1800 psi, and by 1400 they are already below 96% of maximum....
The heaviest pellets peak in velocity at about 1600 psi, but are still at 96% of maximum at 1100 psi....
Medium weight pellets are in between.... peaking in velocity at about 1700 psi, and dropping below 96% of maximum velocity at about 1200psi....
Heavier pellets delivery more energy than light ones, no question about that trend.... Twisted Evil

When pumped to 2000 psi, the first shot (in my gun, at least) is over 96% of the maximum velocity reached (with that pellet) and over 97% of the average velocity over a shot string terminated at 96% of the maximum (ie at about the same velocity as the first shot), with all pellets tested....

I used ChairGun2 to look at the trajectory over the tolerances used.... Using Hobby pellets sighted at 30 yards for the average (890 fps) velocity, the highest velocity (901 fps) would print 0.05" high, at 96% (865 fps) they would be 0.14" low, and at 90% (811 fps) they would be 0.50" low....

For the Kodiaks, sighted at 30 yards for the average velocity (701 fps), the highest velocity (710 fps) would print 0.08" high, at 96% (682 fps) they would be 0.19" low and at 90% (638 fps) they would be 0.74" low.... Obviously if you go further out, these numbers increase....

For my level of skill and intended use, the vertical spread between the highest velocity and the 96% velocity will work fine.... For serious work, I won't shoot the gun down to the 90% point.... I'll use pellets between 14 and 18 grains, which means I'll pump to 2000 psi and stop shooting at 1200 psi.... That will give me about 25 shots within a 1/4" vertical spread at 30 yards because of velocity variation.... I can't shoot that good.... Embarassed

It looks like Crosman / Benjamin have really done their homework on the Discovery.... It took me 120 pumps from empty to fill the gun to 2000 psi.... When you shoot it down to 1000 psi, it takes nearly 10 pumps just to bring the connecting hose up to 1000 psi (at least it takes 10 until the guage on the pump reads 1000 psi).... and then another 60 to get the gun back up to 2000 psi.... Basically, if you shoot it down to 1000 psi, you get about 30 shots and it takes about 70 pumps to top it back up to 2000 psi.... not a big deal.... I plan on stopping shooting at about 1200 psi (about 25 shots) and it will take me about 60 pumps to top it back up.... Cool

Bob

kanyon · Silver Status Member

Hobby's are 11.9grs ?

Dam I need some of those for the AR6..what a crack they will make Twisted Evil

..prob well over 1300fps Shocked

Don't care if i hit anything...just want the noise Razz

rsterne · Moderator

I removed the rear plug today, and drilled and tapped it 3/8" x 16 NC.... Then I made a velocity adjuster from a 1.25" long SS socket head set screw.... I drilled and tapped the set screw for a 10-32 threaded rod so that I can use a degassing tool just like on a stock Disco.... I also turned a spring seat on the inner end of the set screw....

This allowed me to experiment with different hammer spring tensions.... I found that with the adjuster screwed in flush with the lock nut, you could barely cock the hammer safely, so that became the maximum tension.... All other shot strings were measured with the adjuster turned OUT from that point....

The first graph is similar to the one in the original post in this thread.... except that all strings were shot with JSB Exact 15.9 gr. pellets and the variable was the hammer spring tension.... You can see that at maximum tension the velocity starts high and begins to decrease immediately.... As the tension is decreased, the maximum velocity drops, but the number of shots increases.... In all cases, only the shots greater than 90% of the maximum velocity are shown.... I didn't do a shot string at 7 turns out.... Wink

The second graph leaves out the maximum and minimum tension curves, and is limited to only those shots within 96% of the maximum velocity reached for the rest of the curves (instead of 90%).... ie all shots shown are within plus or minus 2% of the average velocity.... The curves don't "look" as flat, but that is because the velocity scale on the graph covers a narrower range.... Now you can really see what effect the Velocity Adjuster has on the shot string.... Here is a summary of the results.... Shocked

Number of shots within 96% of maximum, average velocity, pressure range used:

Maximum: 8 shots, 863 fps, over 1700 psi (you might stretch the string a touch by filling to ~2100 psi?)
4 turns out: 17 shots, 833 fps, 2000 down to 1450 psi
5 turns out: 21 shots, 812 fps, 2000 down to 1350 psi
Stock: 25 shots, 799 fps , 2000 down to 1200 psi
6 turns out: 27 shots, 786 fps, 1950 down to 1250 psi
8 turns out: 33 shots, 725 fps, 1800 down to 1000 psi

If you are interested in the maximum power available and only a few shots for hunting.... you might experiment with the top end of the tension range.... If you are interested in target shooting at close range where you can stand a bit lower velocity and you can get away with a 10% total variation of velocity.... then you can stretch the shot string to over 50 shots.... With the rest of the gun stock, the only part of the Velocity Adjuster that I can see using for my purposes is between about 5 and 6 turns out, ie right around where Crosman's stock spring is.... It looks like Crosman did a damn fine job on their selection of the hammer spring, at least for the .22 cal Disco.... Cool

Next up is to remove the breech and barrel and drill out the transfer port and barrel port.... I can't wait.... Twisted Evil

Bob

rsterne · Moderator

I drilled out the ports on the .22 cal Disco today.... I took the barrel port from 0.134" to 0.166" (#19 drill).... the transfer port from 0.140" to 0.161" (# 20 drill).... and I found that the valve was actually a few thou under 5/32" so I drilled it to that size (0.157").... I have not as yet streamlined the ports in the valve because I wanted to do mods that did not require disassembling the main tube with the fill connector and guage fittings.... Before you ask, I drilled the valve (in place) with a regular drill until I just touched the valve stem, then changed to a drill with the end ground flat, then removed the burrs by hand.... I used compressed air to blow out any remaining chaff from the exhaust port area of the valve.... Wink

I found a few interesting things when disassembling the Disco.... First, in order to remove the action from the stock, you have to remove the safety.... There is a tiny hairpin spring in a little groove in the trigger guard in front of the safety you have to hold forward with a piece of wire so that you can push the safety out to the side.... Then you can remove the single large phillips screw and get the action separated from the stock.... Second, when you pull the bolt back, you cannot get at the 4-48 screw that holds down the breech.... it's further aft than on a 22XX or 13XX gun (ie the breech is different because of that and also because of the recess for the barrel sleeve where the sight mounts).... To get that screw out, you must unscrew the bolt handle and remove the rear plug and hammer spring.... you can then slide the hammer and bolt back far enough to get at that tiny screw.... Shocked

The hammer is a 22XX hammer with a cut-out on top to miss the 4-48 screw (which is further back).... The barrel is from a 2260 (or 1760 in the case of .177).... The sleeve where the rear sight mounts is held on by a set-screw under the sight.... Rolling Eyes

I did shot strings at four different settings, using JSB Exact 15.9 gr pellets.... 4.5, 5, 5.5, and 6 turns out on the Velocity adjuster (ie only 1/8" total adjustment).... The closest string to stock (in length) is the one at 5.5 turns out and it was obvious I picked up about 35 fps (about 2 FPE) with the larger ports.... Twisted Evil

When you examine the 4.5 and 5 turn strings you will notice that the peak velocity is very close (only 4 fps difference) and so is the average velocity (854 vs 848 fps).... You get one less shot at 4.5 turns than at 5 turns, but the big difference is how fast the pressure drops at 4.5 turns compared to 5 turns.... at 20 shots (past the 96% curve) it is down 100 psi more.... and at 25 shots it is down 200 psi more.... Shocked

.... If you were interested only in maximum power for hunting and could live with less than 20 shots, somewhere between these two settings should be a "sweet spot" where you could get 15 or 16 shots within about 1% of 850 fps.... You would only shoot down to about 1500 psi, making for a quick top-up.... Twisted Evil

I like the look of the curve at 5.5 turns out.... 24 shots within a 4% range of velocity, or 22 shots within 11 fps of the 832 fps average.... What I actually settle on will depend on which pellets my Disco likes for accuracy.... Once I know that, I'll fine tune the adjuster to get the "best" string for what I want.... Realistically, there are lots of choices, depending on how many shots you want at what velocity.... If you choose lower velocities, there is no point in pumping to 2000 psi.... 1900 psi (maybe even 1800 psi) will actually work better if you're trying to hold velocities within that 96% range.... Cool

Bob

rsterne · Moderator

I pulled the Leapers 3-9 x 40 AO Scope off my Phantom.... have to get 2-piece rings to do the job properly, but at least you can see what a beauty she is.... Mr. Green

I can't believe the quality of the stock.... downright gorgeous.... Shocked

Bob

Alstone · Moderator & Site Supporter

That’s one of the best technical reviews I have read on the Disco Bob, it certainly must have been a bit of a marathon doing it. Not having a Disco but I keep looking at them basically because of the reported ease of pumping up to pressure, one thing that I was not impressed with was the shot count, I expected more than 25-30 good shots and this is a .22, if I do get one it would be a .177 no particular reason I just like .177 cal. The question is if you get 25-30 good shots with .22 and knowing that .177 uses more air then the shot count would be lower, which going on your figures doesn’t look good , what do you think?

I saw on another site a guy had also made a velocity adjuster similar to yours but complained that he had lost the use of the de-gasser, evidently he hadn’t seen your post. Laughing

Al

rsterne · Moderator

HI Al....

The Disco has a relatively small air chamber for a PCP.... only 135 cc.... that, plus it's only pumped to 2000 psi (and it really is easy to pump).... Wink

The length of the shot string depends entirely on how much variation you are willing to accept.... and that realistically depends on your shooting distance and the size of your intended targets.... I chose 96% because I'm fussy.... If you chose 90% (which is how I think the Disco is intended to be shot), it's already in the 30 shot range (50 if you drop the velocity down to about 700 fps).... I'm getting 24 shots (@ 832 fps with 15.9 gr. pellets) within the 96% window.... Cool

I don't quite follow your argument about why .177 would be worse.... Crosman rate the .177 Disco at 1000 fps while they rate the .22 at 900 fps.... That would indicate to me that the .177 has less FPE (consistent with what I found about the relationship between pellet weight and energy).... If that is the case, I would think the .177 would have a longer shot string.... I could be totally wrong, of course.... Rolling Eyes

Bob

Alstone · Moderator & Site Supporter

I was just working on the fact that .177 uses more air than .22, I understand the increase in fps which I would expect ( lighter pellet etc) but feeding off the same air chamber I just assumed it would run out quicker.

Looking at some figures I have for the Disco and if as you say it is intended to run down to 90% then that would put things about right, what was throwing me was that over here the max output for .177 is set at just under 800 fps and around 35 shots per fill, also the .22 is limited to around 600 fps using 14g pellets, so with the lower power of a max of 12flb the shot count would increase, but I have noticed on one or two forums that people are putting in a 2250 hammer spring and de-bouncer to get more shots.

Al

dummyracer36 · Senior Member

rsterne, your in canada? do they have power restrictions on pellet rifles there? if so, is your disco one of the restricted ones? or is this representative of what a US market disco puts out?

and i have to agree, this is one of the most thorough and informative review of a rifle i've seen outside of a professional magazine!!! great job!!!

rsterne · Moderator

They have a 500 fps limit in Canada or it's considered a firearm.... They don't make a "de-tuned" Disco for Canada, it's the same as the US version....

Bob

rsterne · Moderator

I pulled my Disco apart yesterday and did some work on the valve.... quite a learning experience.... Embarassed

The first thing I did was try and get the valve out the back end of the gun.... BAD idea.... I cut up the O-rings on all the holes in the outer tube.... Evil or Very Mad

.... I spent over an hour carefully deburring all the holes and slots, and after the valve work, put it back together and it leaked past the outer valve O-rings.... Pulled it apart again (from the front, this time), new O-rings again, and it went back together no problem.... lesson one.... Shocked

I had already opened up the transfer port and barrel port, so the purpose of yesterdays madness was to smooth up the corner in the exhaust port.... This pays big benefit in 22XX and 13XX guns in .22 cal, especially at over 700 fps, so I had big expectations in the Disco.... I rounded the corner off quite a bit with a 1/8" ball on my Dremel, and smoothed everything as much as possible.... When I finally got it back together and fired some shots over the Chrony I certainly wasn't disappointed.... I was able to get over 910 fps with 15.9 gr. Exacts, so I had picked up about 50 fps.... Twisted Evil

How were the shot strings you ask?.... Bad enough I won't even post them !!!.... Sad/Cry

.... I picked up a ton of velocity, to be sure.... but it's WHERE I picked it up in the shot curve that isn't good news.... the biggest increases in velocity occurred at around 1600 psi, so the curve is nowhere near as "flat" as before I modified the valve.... I'm beginning to understand just how an un-regulated PCP works, though, so I guess that's good news.... lesson two.... Laughing

The first part of the shot string, from 2000 psi down to 1800, has a very "clipped" report because the valve is in partial lock.... This part of the curve had hardly any change with the hogged out ports, probably because the pellet is getting a short, sharp kick from a relatively small amount of air at very high pressure.... very efficient, very little pressure loss per shot, and also very difficult to gain much other than by a harder hammer strike....

The next part of the curve, from about 1800 psi down to (after the valve mod) about 1600 psi, shows an increase in velocity and report as the partially locked valve begins to flow more air through the (now enlarged) ports.... By the time you get to 1600 psi, those bigger ports are breathing great, and the velocity is greatly improved.... Cool

From about 1600 psi on down, the whole curve is elevated compared with the stock ports, because the valve is venting its charge more efficiently.... This part of the curve is about as smooth as before.... Interestingly, I didn't notice any loss in the total shot count if you look at the "long" string down to 90% of the peak velocity.... ie you still get about the same number of shots within 90% of peak as before (with the same hammer spring setting) and at a higher velocity.... indicating that the streamlined ports definitely improved the guns efficiency (total FPE increased from 2000 psi down to 1000 psi).... The problem is that the curve is more of a curve (no noticeable flattening in the middle), and the shot-to-shot consistency is much poorer.... Evil or Very Mad

If you are willing to accept a short shot string in exchange for a big increase in power (3 FPE) there is probably some merit in hogging out the ports and increasing the hammer spring preload maybe 1/8" more than stock.... You might get a smoother shot string with even heavier pellets, but that's not what I'm after.... Ideally, I want 900 fps with stock pellets, and about 870ish with 16 gr. and a 20 shot string within a 4% window of velocity (ie plus or minus 2% from the average).... My next step will be to put back in a stock (0.140") transfer port while leaving the other mods alone and see if I can flatten out the middle of the shot string.... Wink

I now believe that the Disco is pretty good, just the way Crosman built it.... Shocked

Bob

rsterne · Moderator

Finally got back to working on the Disco today.... had a fall and tore all the muscles in the back of my right thigh a couple weeks ago.... plus I've been waiting for the JSB Exact Heavy (18.0 gr) pellets to arrive.... I did a shot string with the Heavies, still using the same hammer spring tensions as for the last tests (5 turns out from coil bind) and they had the same erratic velocity as did the Exacts.... so I cranked the adjusted in one turn.... and it transformed the gun.... Twisted Evil

I shot strings starting at 2000 psi down to where the velocity dropped to 96% of the maximum reached (about 1400 psi).... I used 3 pellets, JSB Express 14.3 gr, JSB Exact 15.9 gr, and the new JSB Heavy 18.0 gr.... The graph below also shows the shot string for my stock Disco, and for the stock gun with the adjuster set at 4 turns out from coil bind (like the testing I did today).... The stock strings were with JSB Exact 15.9 gr pellets....

The mods done are: drill the transfer port to 0.161"; drill the barrel port to 0.166"; drill the valve exhaust port to 0.157" and round the corner between the seat and exit.... As of yet I have NOT tried thinning the valve stem.... As you can see, the shot strings are about the same length as as the stock string at 4 turns out.... with an increase from an average of 833 fps to 901 fps using Exact 15.9 gr pellets.... The stock gun / hammer spring setting gave 797 fps with the same pellets.... so I have gained a full 100 fps over stock.... Shocked

Here is the summary: Number of shots over 98%; Number of shots over 96%; Average velocity (to 96%); Average Energy (to 96%);

JSB Express 14.3 gr: 13 shots, 18 shots, 935 fps, 27.8 FPE
JSB Exact 15.9 gr: 11 shots, 15 shots, 901 fps, 28.7 FPE
JSB Exact Heavy 18.0 gr; 16 shots, 20 shots, 848 fps, 28.8 FPE
Stock 4T out, Exact; 15 shots, 17 shots, 833 fps, 24.5 FPE
Stock Disco, Exact; 18 shots, 24 shots, 797 fps, 22.5 FPE

For some reason, the 15.9 gr Exacts are still a bit eratic from 2000 psi down to 1900 with the modded ports.... I suspect that by playing with the hammer spring tension a bit I could smooth out the curve some more.... What I end up with will depend on how accuracy testing goes when I have a chance to shoot outside.... So far, I'm VERY impressed with the new JSB Exact Heavy pellets.... With the current setup, they have a nice flat shot curve right at 850 fps which is nearly 29 FPE.... I'm getting 20 shots between 826 fps and 860 fps with 16 of those between 843 fps and 860 fps.... Top-up from 1400 psi back to 2000 will be pretty easy, too.... Twisted Evil

Bob

rsterne · Moderator

I had a chance to play around with my Disco again today.... I wound the velocity adjuster in until the gun wouldn't cock because the hammer spring was coil bound and then backed it out about a third of a turn until it would cock reliably.... I pumped it to 2000 psi and shot 10 shot strings with 5 different pellets.... At that point, the pressure had dropped to about 1500 psi and took 50 pumps to top back up....

RWS Hobby 11.9 gr.
1067
1060
1060
1053
1045
1031
1027
1019
1008
995
Average 1036 fps; 28.4 FPE; 35% increase over stock.

JSB Jumbo Express 14.3 gr.
1007
1019
1009
1010
1004
989
984
974
966
958
Average 992 fps; 31.3 FPE; 44% increase over stock.

JSB Exact Jumbo 15.9 gr.
969
979
973
975
963
954
956
938
932
926
Average 956 fps; 32.3 FPE; 44% increase over stock.

JSB Exact Heavy 18.0 gr.
913
923
929
930
934
923
921
916
907
896
Average 919 fps; 33.8 FPE; 48% increase over stock

Weirauch Magnum (Beeman Kodiak / H&N Barracuda) 21.6 gr.
861
877
866
868
880
850
868
858
855
847
Average 864 fps; 35.8 FPE; 52% increase over stock.

A few conclusions can be drawn from these results:
1. Lighter pellets have the highest velocity at the beginning of the string (2000 psi), while heavier pellets peak at about 1800 psi.
2. The lighter pellets had about a 7% velocity loss across the 10 shots, while the heavier pellets varied only about 4%.
3. Heavier pellets gained more energy from the modifications performed than light pellets.

One thing I noticed after compressing the hammer spring to coil bind was that it "set" somewhat and lost about 0.1" of length with no load.... This means that if you start from a "stock" setting with a velocity adjuster and work your way up.... when you work your way back, the velocities will no longer be the same, but less, at the old settings.... Shocked

The modifications done to my Disco to achieve the above results were:
Barrel port drilled to 0.166"
Transfer port drilled to 0.161"
Valve port drilled to 0.157" (5/32), with the corner rounded off significantly
Velocity adjuster (cranked to the max)

I think that you could get the Disco to "Mach" with Hobbies with just a little bit more tweaking.... it's REALLY close.... Twisted Evil

.... I don't have any interest in doing so, but the challenge is there for anyone so inclined.... Any gun with as much power as a modified Disco is really far better off with heavier pellets, however.... Wink

These strings are pretty short, but they give an idea of what you can get out of a Disco if you only need a few good shots.... One other thing I should mention.... this thing is LOUD at these power levels.... not to mention it takes about twice the number of pumps per shot as a stock Discovery.... Embarassed

I didn't say it was an efficient set-up.... but it's certainly got lots of POWER.... Twisted Evil

Bob

rsterne · Moderator

I got two new springs for the Disco today.... one is a new trigger spring from 0.020" wire (instead of 0.028").... It completely transforms the trigger (and also the one on my 2260, same trigger).... There are two springs in the trigger box, a coil spring behing the trigger (the one I replaced), and a hairpin spring on the sear.... By replacing the trigger spring with a lighter one, you get a two-stage effect.... Cool

With the original trigger spring, you could barely tell when you hit the sear spring.... It took about 1.5 lbs to start moving the trigger, by the time you hit the sear, it was at about 2.5 lbs, and at release about 3.5 lbs (on both my Disco and 2260).... With the new spring, the pre-travel (1st stage) is less than 0.5 lb, with a sharp increase in resistance when you hit the sear.... The trigger breaks cleanly at about 1.5 lb, and yet is "safe" because you haven't touched the sear spring.... Twisted Evil

The other spring is a stiffer hammer spring from 0.040" wire.... It is about 1/8" longer than a Disco spring, and about 1/3rd stiffer.... otherwise dimensionally similar.... and a drop in replacement.... Since my gun has a velocity adjuster (hammer spring tensioner) I dropped it in, and cranked it all the way to coil bind, then backed it off 1/4 turn so the gun cocks reliably.... The increase in trigger pull is nominal, maybe 0.2 lb.... :wink:

Anyone who has played with tuning a Disco will have realized that the hammer spring is one of the limiting factors in velocity.... Even cranked all the way to coil bind, with a stock spring the gun barely maxes out at 2000 psi with light pellets, and with pellets in the 18-21 grain range, the peak velocity is reached at about 1800 psi.... The more efficient you make the gun (porting improvements, etc.) the lower the pressure where the velocity peaks.... Although Crosman tell you not to pump the Disco over 2000 psi.... their reason in the instructions is based on performance (more pressure reduces the velocity) and not having the valve "lock".... Many have commented that the "yellow" range on the guage extends to about 2500 psi.... I take this to mean that the gun design is "safe" to about 2500 psi, and I can't imagine Crosman not building in a big safety margin.... Please note, this is my personal opinion, and I am NOT recommending that you pump the Discovery over 2000 psi....

Having said that, now that I presumably have a spring capable of dumping more than 2000 psi, I promptly pumped my Disco to the top of the yellow zone on the guage, which is about 2500 psi according the the guage on my pump.... I shot a few shots with various weights of pellets, until the velocity was obviously decreasing, and recorded the maximum velocity reached:

RWS Hobby 11.9 gr: 1110 fps = 32.6 FPE (no sonic crack, but it must be awfully close)
JSB Express 14.3 gr: 1059 fps = 35.6 FPE
JSB Exact 15.9 gr: 1023 fps = 37.0 FPE
JSB Heavy 18.1 gr: 972 fps = 37.8 FPE
RWS Magnum (Kodiak) 21.6 gr: 915 fps = 40.2 FPE

Yes, folks, the Disco breaks 40 FPE with a stock volume valve.... Twisted Evil

The lighter pellets peaked at about 2400 psi, and the JSB 18 gr. at 2300, but the Kodiaks had a nice shot string peaking at about 2100 psi and continuing down to about 1700:

889
897
904
905
914
907
913
910
915
915
910
908
899
893
888

Note, all 15 shots are within 96% of the maximum velocity.... This is a VERY good string.... Twisted Evil

I am waiting for some EunJin pellets from AirGunEric.... and some of the new H&N Rabbit Magnum II's from Cibles.... Although I have a new B&A Max-Flow Valve sitting here.... already drilled to mount in the Disco.... I want to test the heavier pellets before taking the gun apart to test the new valve.... Rolling Eyes

Stay tuned.... Mr. Green

Bob

sniper · Silver Status Member

bob,

will you buy a maruader next and report back???? Laughing