Okay, it was a bit of an anticlimax... first, I've run out of air.
I can only get a 2700psi fill.    so the shot string is about  
1 mag (8 shots) short.
I'm getting about one mag to 220psi tank pressure.
This is not to bad considering that a lot of the shots were well 
over 31fpe. 
I'll get the scuba tanks refilled this week and do some more numbers.
However it should end up at around 45 shots per fill.
If I swap out one 0.005" shim in the spring stack for a 0.002" one, it'll
put us right at 30fpe and add another mag full of shots to the full power string.
bringing it up to about 50 full power shots. I could live with that.
Accuracy is unaffected and it's making one hole at 20yds... as it should
at such a short distance. I'll take it out to Joel's place later today and
try it out at 50yds.
I'll keep you all posted. Here's shot string over 30 shots starting at 2750psi
and ending at 1800psi..

Rifle	HPA 850HP in .22
Pellet	JSB Jumbo
Weight	15.9
Shot #	FPS	Dev From Avg	Stats
1	951.2	1.5	Max	952.8
2	950.4	0.7	Min	946.5
3	949.3	0.4	Average	949.7
4	946.7	3.0	Standard Deviation	2.0
5	946.5	3.2	Extreme Spread	6.3
6	950.1	0.4	Energy	31.9
7	949.4	0.3	Average Deviation	1.5
8	951.7	2.0
9	949.3	0.4
10	952.8	3.1
Rifle	HPA 850HP in .22
Pellet	JSB Jumbo
Weight	15.9
Shot #	FPS	Dev From Avg	Stats
11	948	5.6	Max	948.5
12	946.3	3.9	Min	935.8
13	948.5	6.1	Average	942.4
14	945.7	3.3	Standard Deviation	4.6
15	943.1	0.7	Extreme Spread	12.7
16	939.6	2.8	Energy	31.4
17	940.3	2.1	Average Deviation	3.9
18	936.7	5.7
19	935.8	6.6
20	940	2.4
Rifle	HPA 850HP in .22
Pellet	JSB Jumbo
Weight	15.9
Shot #	FPS	Dev From Avg	Stats
21	933.8	8.6	Max	936.3
22	936.3	11.1	Min	915.5
23	930.1	4.9	Average	925.2
24	928.2	3.0	Standard Deviation	6.8
25	925.7	0.5	Extreme Spread	20.8
26	922.7	2.5	Energy	30.2
27	915.5	9.7	Average Deviation	5.6
28	919.3	5.9
29	921	4.2
30	919.4	5.8

The 850 Store

very interesting i know its possible to make 30fpe and more out of the 850 just need to figure out how to get the most amount of shots,. what spring are u using to drive the hammer? keep up the good work,

Thanks Jovan, I'm having my own spring made now.
It's just easier than dealing with spacers and cutting and testing springs.
I did the shim swap this afternoon and now it starts out at 946fps with 15.9gr 
and stays more consistent for 5 and a half  mags. A much better spread.
However the regulator has not settled in yet, I put about 150 shots over the
chrony testing this afternoon and its picked up about 5fps average and should
stay put now. 
I think I might just leave it like this. 
Accuracy is good, but it does produce the occasional flyer.... I think I may have
burred the breach in my rush to get it together for testing.
I''ll take it apart next weekend and check.  

The 850 Store

At that power level and resulting shot count just sounds fantastic to me....and if you are a hunter,more than enough...sure beats my Disco .22 shooting at 906 AVG (20 high power shots)...

Have you tried 14.3gr pellets..??? Be interesting because that is weight pellets I hunt with in the Disco...

Anything around 950 FPS is ideal in my book...

Thanks Rich, well Benji HP's (14.3gr) are doing around 970 to 980fps. The barrel
on this 850 is not a very good one though and does not like CP's or the Benji HP's much.
It loves JSB's though and I have bought some Beeman's, a few different .22 types
to try out in it.

I got it up to just over 1000fps with CP's, but it was not practicle and also it blew the output
burst disk after a while, so I had the regulator up at or close to 2700psi for that to happen,
basically no regulator at all....
Just to confuse testing it blew again later after I got junk sucked into the seat
area by me getting sloppy and not cleaning it up prior to each reassembly...it takes
so much darned time. So more haste, less speed
Anyhow, this got me doubting what was going on and got me to take it apart again and
hook it back up to the pressure test rig to check the pressure... it was okay at 2000psi.
Anyhow, Its at 1975psi now, I'll dial it back to 1950 and still about 30fpe, it should be
better.

The 850 Store

Roald is cocking the gun getting harder? i noticed that it got harder to cock when i got into HPA, this is the main reason why i i made a new valve that would runn on the stock spring and be easy to cock, on the stock spring im able to get 820fps in 16g and it is very easy to cock, i also have another valve that runs on the stock spring with a spacer and gets near 850 fps in 16g, im very picky on how hard it is to cock

Jovan, it is harder to cock, but to help it I have modified the hammer
slightly to be simmilar to the european style 1250 where the spring guide is long
and a shaft is drilled into the back of the hamemr for it to slide into.
This keeps the hammer, spring and guide in line and makes cocking a lot
smoother.
I'll take pics of it when I pull it apart next time.
I also found that shortening the bolt handle helps a lot too.
But at the end of the day you still get that accasional cock that "sticks"
and needs a firm "tug" to complete it.
I've become so used to it now though that I don't even notice it any more  

The 850 Store

You can probably improve barrel accuracy by "fire lapping" pellets with lapping paste...or valve grinding compound (fine)...I did that to my 850 .177 barrel plus a re-crown with the brass screw/drill motor trick...LOL..

I just rolled pellets in the lapping compound and loaded them in the breech with long tweezers.(no magazine).....think I shot about 15 thru barrel...then cleaned barrel good and test fired it on target...best to test fire in no wind..

I'll try that if I find that is was not fault... I kinda rushed the breech job and my have left
a bur in there.    

The 850 Store

in your 850 .22 HPA project...based on my experiences with the 850 HPA .177, I'm hopeful the .22 will follow....I think the Umarex barrel is still a good platform to tweak,improve on...especially using a good design air stripper...

I've learned that USFT's with HW barrels are not any better..and same goes for Daystate Wolf,HW 100's,etc...

So far in various competition I've been in,the FX Cyclone is the only sporter rifle I've seen to be equal with the USFT's in 50 yard group sizes...and that was a .22 caliber...
Knowing my 850 HPA .177 has shot several groups of .400" at 50 yards...makes me very optimistic about the 850 .22...

Here is final total agregate scores for 3 shot groups in my last 50 yard match by air rifle..these scores were shot in varible 3-7 mph crosswinds...(30 bulls..3 shots each...)

USFT Hunter, 5mm, Leup 24X .499"

FX Cyclone, .22, Leup 6-24 .504"

USFT, .177, Hakko 12-60 .660"

My 850 HPA, .177, .674"

FWBP70, ,177, .804

HW100, .22, Leup 6-24 .869"

Daystate MKIII, .22, .903"



Hang in thre Roald...you have another winner coming...

This is getting insane! 950fps with 15.9 grain pellets out of the platform designed to shoot half that speed.

Modified hammer, valve, adapter, stock, air source, safety, trigger, transfer ports, breech, spring, stock, after market adapter (modified too), modified magazines and modified after market regulator.

I think the only original part is the bolt.

God speed Roald, you are the man and I salute you.

Chris

Thanks Chris.... but it's so much fun
It'll do over 1000fps with 14.3gr pellets, but I can't get the balance
right to make it worth while doing yet. However, Jovan has a really nice
valve and hammer mod the will help I'm sure.
The valve starts to "self regulate" at anything close to 2000psi, plus I think
it's too high for the gun / materials to take and last a long time.
The Dominator lets roughly 2200psi out of the valve while it's charged
up to 4500psi, and it's letting out 1900psi when the pressure drops to 3000psi
at which pressure it only produces around 900fps with a 14.5gr pellet. 
We are getting well over 900fps with the 850 at 1800psi with a 14.5gr .22 RWS
Superdome.  

The 850 Store

to 30fpe at a full charge and then see what the shot count looks like.
I want at least 5 mag fulls at a constant 30fpe.
I'll let you know what happens.

The 850 Store

I swapped them out tonight.... I took out a 5 thou and replaced it with a 3 thou shim.
Its shooting right at 970fps with 14.5gr SuperDomes.
This gets up to 30fpe. I'll do a shot count test tomorrow morning and let you
know if this bought us the two extra mag fulls I was looking for.
I'll have to run down to the scuba shop and get my tanks recharged first though.  


The 850 Store

I just filled it up and loaded it up with JSB Jumbo's and it's still up at 31.3fpe.
It only lost about 5 fps by reducing the regulator spring stack preload by 2 thou.
I'll have to reduce it again. I'll only drop it 1 thou though. I lot of effort for a tiny
adjustment..... but I want to keep it at 30+ not 29+ .... it's just not the same
However, it is very consistant through the first mag, 942fps almost nuts on each shot. 

The 850 Store

I have not changed anything since last night so it's still .001 to stiff in the spring stack:
Dropping that 1 thou will land us right on the spot.It should shave about 3fps off each
shot, giving us that 5th mag full per fill at safely over 30fpe. (full power)
I'm excited now, if the final adjustment pans out and it stands up to the normal 8000 pellet test
without showing any signs of change, I'll put it into production.
This will make a very nice hunting rig.
BTW. This was from 2800 psi down to 2000psi. I'll go get those scuba tanks filled today. 

Rifle	HPA 850HP in .22
Pellet	JSB Jumbo
Weight	15.9
Shot #	FPS	Dev From Avg	Stats
1	947.4	6.1	Max	947.4
2	946.6	5.3	Min	937.8
3	937.8	3.5	Average	941.3
4	938.6	2.7	Standard Deviation	3.5
5	939.1	2.2	Extreme Spread	9.6
6	944.3	3.0	Energy	31.3
7	939.4	1.9	Average Deviation	2.9
8	940.9	0.4
9	939.9	1.4
10	938.6	2.7
Rifle	HPA 850HP in .22
Pellet	JSB Jumbo
Weight	15.9
Shot #	FPS	Dev From Avg	Stats
11	941.3	0.4	Max	944.4
12	944.4	2.7	Min	939.2
13	939.2	2.5	Average	941.7
14	941.6	0.1	Standard Deviation	1.6
15	943.1	1.4	Extreme Spread	5.2
16	941.8	0.1	Energy	31.3
17	940.6	1.1	Average Deviation	1.2
18	943.4	1.7
19	941.9	0.2
20	939.9	1.8
Rifle	HPA 850HP in .22
Pellet	JSB Jumbo
Weight	15.9
Shot #	FPS	Dev From Avg	Stats
21	944.5	92.5	Max	944.5
22	40.3	811.7	Min	40.3
23	942.9	90.9	Average	852.0
24	944.2	92.2	Standard Deviation	285.2
25	943.2	91.2	Extreme Spread	904.2
26	940.8	88.8	Energy	25.6
27	940	88.0	Average Deviation	162.3
28	943.7	91.7
29	939.3	87.3
30	940.9	88.9
Rifle	HPA 850HP in .22
Pellet	JSB Jumbo
Weight	15.9
Shot #	FPS	Dev From Avg	Stats
31	939.7	2.5	Max	941.3
32	941.3	4.1	Min	932.5
33	941.2	4.0	Average	937.2
34	938.2	1.0	Standard Deviation	3.2
35	939	1.8	Extreme Spread	8.8
36	936.7	0.5	Energy	31.0
37	935.1	2.1	Average Deviation	2.7
38	934.8	2.4
39	933.1	4.1
40	932.5	4.7

The 850 Store

It's still a bit too hot... I took out the 1 thou shim and now we
have the string below.
Almost there. I'll put a few thousand pellets through it and see
how it does. It should settle down a bit. I'll re-chrony it after
about 250 shots, the regulator should be nice and solid then.
It looks like I could drop it 1 more thou and it'll still average just over
30fpe though.... and add another mag to the shot count.
I am going to leave it like this for now though and wear it in a bit. 

Rifle	HPA 850HP in .22
Pellet	JSB Jumbo
Weight	15.9
Shot #	FPS	Dev From Avg	Stats
1	937.9	0.4	Max	940.1
2	940.1	1.8	Min	936.7
3	938	0.3	Average	938.3
4	937.1	1.2	Standard Deviation	1.3
5	936.7	1.6	Extreme Spread	3.4
6	940	1.7	Energy	31.1
7	939.5	1.2	Average Deviation	1.1
8	936.8	1.5
9	937.9	0.4
10	939.1	0.8
Rifle	HPA 850HP in .22
Pellet	JSB Jumbo
Weight	15.9
Shot #	FPS	Dev From Avg	Stats
11	940.1	1.8	Max	940.3
12	940.3	2.0	Min	933.9
13	940	1.7	Average	938.3
14	939.7	1.4	Standard Deviation	2.1
15	938.8	0.5	Extreme Spread	6.4
16	937.7	0.6	Energy	31.1
17	936.5	1.8	Average Deviation	1.7
18	933.9	4.4
19	936.7	1.6
20	939.3	1.0
Rifle	HPA 850HP in .22
Pellet	JSB Jumbo
Weight	15.9
Shot #	FPS	Dev From Avg	Stats
21	940.2	1.1	Max	941.4
22	941.4	2.3	Min	936.2
23	939.7	0.6	Average	939.1
24	938.3	0.8	Standard Deviation	1.9
25	936.2	2.9	Extreme Spread	5.2
26	937	2.1	Energy	31.1
27	937	2.1	Average Deviation	1.6
28	940.1	1.0
29	939.7	0.6
30	941.3	2.2
Rifle	HPA 850HP in .22
Pellet	JSB Jumbo
Weight	15.9
Shot #	FPS	Dev From Avg	Stats
31	938.1	0.1	Max	940.2
32	939.9	1.9	Min	935.1
33	937.3	0.7	Average	938.0
34	938.2	0.2	Standard Deviation	1.5
35	939	1.0	Extreme Spread	5.1
36	936.7	1.3	Energy	31.1
37	935.1	2.9	Average Deviation	1.1
38	937.8	0.2
39	938	0.0
40	940.2	2.2
Rifle	HPA 850HP in .22
Pellet	JSB Jumbo
Weight	15.9
Shot #	FPS	Dev From Avg	Stats
41	936.7	1.2	Max	937.4
42	937.4	1.9	Min	933.1
43	936.9	1.4	Average	935.5
44	935.4	0.1	Standard Deviation	1.4
45	933.1	2.4	Extreme Spread	4.3
46	936.7	1.2	Energy	30.9
47	934.5	1.0	Average Deviation	1.1
48	935	0.5
49	935.3	0.2
50	934.16	1.4

The 850 Store

From it's initial platform to this, you will have to excuse me while I pick my jaw up from the ground!


Graeme

If it ain't broke you arn't trying hard enough

ES,SD looking really good....can't wait to see groups at 25/30 yards....

Thanks Rich, the regulator is really sweet. Almost zero bleed up too..
Lets see how long this lasts.
I'm wondering if its partially the valve thats regulating too, helping it
stay so flat. 

The 850 Store

Thanks Graeme, it's a good platform for sure.

The 850 Store

nt

If it ain't broke you arn't trying hard enough

It's the stock 24" barrel.... well 23 3/4"    

The 850 Store

hmmm the longer I look at those numbers (SD and ES) and compare them
to the usual standard deviation and extreme spread, the more
they look unusually low.... well I'm used to seeing single figure
SD's but extreme spread is usually a bit higher than that. usually
at or close to 10. I have shot three more fills through it and
they are still very low. It may just be a very sweet regulator or
we are onto something here. Maybe the valve is regulating a bit also
at these high pressures?
Also, I seldom waste JSB's on strings like this, could that also
be a factor?
Somethings definitely up....

The 850 Store

using JSB's...remember,they have softer skirts than Crosman's...so the air is expanding the skirt more and the JSB is biting into the rifling more..at least that is my opinion after numerous tests in my 850 HPA .177...

ES and SD are the data I look at..I have also got lower ES/SD with the heavier pellets...(10.2 gr vs 8.4 gr)...

10.2 gr = ES 11.24/SD = 3.66 at 961 FPS avg...

8.4 gr = ES 14.54/SD = 4.24 at 1011 FPS avg...

In your .22,an interesting comparison would be 14.3 vs 15.8...

The regulator has much to do with this...

Youre right, I'll try the CP's and see. At least that will show how much the more consistant size
and weight of the JSB's is helping these numbers..... but still they are scary low.
I was testing at a buddies place the weekend and not at home. I'll also chase it through my chrony
and see if the two agree.

The 850 Store

I have heard the 850 barrels have just a tad more choke than some other barrels...that may also be a factor.
My friend has a USFT with an HW barrel and he gets an occasional flyer using JSB heavies..but I never get flyers using same batch (die) pellets in my 850.
We were discusing this at a match and Tim McMurray mentioned that and said LW barrels have more choke.