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PCP - HPA - C02 Gate => PCP DarkSiders Forum => : melloroadman October 14, 2008, 11:40:00 AM
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What rifle other than the Discovery has a low fill of about 2000 -2200 in .22 cal. and what is the shot count .Marvin
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Only ones that come to mind would be a Mac1 USFT, a Big Ed tuned B 50/51, and some Talons. Found out after I traded it off that one of my Talons had been shooting very nicely at only 2300 psi fill level. I believe any of the above will get 40 shots or more. That said, most any PCP can be tuned to shoot at lower fill levels, you just have to be willing to give up some power. Later.
Dave
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Yes but I want to keep the fps up for 50 - 75 yard shoots .Marvin
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My HPA 850 will give about 30-40 shots of 750 fps from 2200 to 1250 psi
A well dialed-in talon with 18" or 24" barrel would easily do the same
Chris
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I would like to stay away from the talons .Marvin
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melloroadman - 10/14/2008 9:06 PM
I would like to stay away from the talons .Marvin
But Why?????? ;)
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Not my cup of tea .Marvin
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Hehehe, that's what I thought, until I shot one....
I resisted for 3 months and then gave in.
There is no cure for this
Chris
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Buy tuned from Ed or tune it yourself in minutes, do look at :
http://www.klickcue.com/air_rifle/%3Cspan%20class='highlight'%3Eb50%3C/span%3E_51/technical_details_for_adjusting_the_bam_%3Cspan%20class='highlight'%3Eb50%3C/span%3E_51.pdf
Our numbers wont be exactly like a stock one as our hammer is milled 2mm shorter giving more run at the striker and it has a 25" barrel otherwise stock except for the lighter hammer spring. 2000psi fill yields 30fpe - 915fps w/JSB 15.9g for right at 30 shots.
John
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I would go with the B50/51. I tuned my B51 ala 'The Book' and put in a lighter McMaster-Carr hammer spring with a screw power adjuster (adjusts hammer spring tension). I get 40-shots in 0.177 ranging in a smooth velocity per shot curve from 855fps to 915fps with a starting fill pressure of 1850# shooting Crosman Premiers at 10.5gn. They have a good ballistic coefficient so retain the most velocity at 50 yards. You can get a BigEd tuned version in either 0.177 or 0.22 with a Lothar Walther barrel for the best accuracy.
Any better shot to shot velocity consistency would require a higher priced PCP with a regulator or a regulator conversion for an existing PCP - the BSA Super Ten for instance but these also require the dreaded 210 BAR fill prssures. I gen'd up a possible design for a regulator for the Benjamin Discovery but I do not have machine shop capability. The design would allow you to pump the Discovery up to a higher pressure, say 2500#, and regulate the shot pressure to about 1450# (the sweet spot pressure for my Disco 0.22 which I also tuned up).
Ultimately though, it comes down to getting pellets that are both accurate and have the highest ballistic coefficient possible - hence my use of Premier's.
Hope this helps
Scott
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Scott whats the trigger like compared to your Discovery .Marvin
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Marvin:
As you probably know, I did the lower link mod on the discovery and it lets go nicely at about a third of the original pull weight.
As part of the B-51 tune, I did polish all trigger wear surfaces and the part of the hammer weight that contacts the trigger with 600-grit oiled sand paper and lubed with white lithium grease. The trigger was never that bad to begin with and the tune helped it along a bit.
In comparison, the B-51 wins hands down; its trigger is lighter and smoother than the Discovery (after the lower link mod) and adjustable (which I have never tried), but after tuning the Discovery its trigger lighter and smoother than before, but still a harder pull with a bit less predictability. If you do not do the lower link mod on the Discovery, there is no comparison; the B-51 wins all around in any case.
The Discover trigger lower link mod lets it approach a GRT III trigger on a Crosman Quest or Storm XT - smooth but still with some weight to it.
Compared to the AA S400, again, no comparison, the S400 is truly smooth and light.
My lightest trigger comes on my Baikal IZH 46 - light as a feather and the shot always takes me by surprise.
Hope this helps. If I had a pull weight measuring gauge I would get some numbers to you - sorry its all subjective
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N/T
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Now I want a B-51 again...
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I thought about one when I bought my Discovery which I am happy with but . Marvin
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If you do not like to do the tuning, then get a tuned B50/51 from BigEd, otherwise use 'The Book' and tune away. I have 3 McMaster Carr hammer springs left over from my tune if you want one some time. Also, my B51 is 0.177 cal.
And just one other thing, when the foster fill valve on my B51 started leaking, I was able to take it apart and replace the offending o-ring easily, unlike when my AA S 400 fill valve started leaking - you need special tools or knowledge to strip that one down and repair it.
Scott
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I have thought about this more and the .177 is what I would probable get after all . But I think I will wait till after the first of the year . Crosman is suppose to come out with another PCP around then . They have a excellent warranty program and I still question the longevity of the Bam but then that might not be a issue . But I shoot my rifles a lot and I want them to last . Marvin
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I have a Big Ed tuned B51, an AA S400C, and have owned a few other PCP's at this point (Sumatra Carbine, Career 707, FX Black Widow, another B50, TalonSS, HPA converted AR2078T). The B50 I bought off the shelf was a nightmare, no joke there, but the B51 I bought from Big Ed is just the opposite. I think the extra couple dollars($25 IIRC) you spend for the Big Ed B51 is well worth it. Big Ed goes through them and solves any issues so you wont get a dog like the first one I bought off the shelf. My B51 is one of the most accurate guns I have ever owned, including my AA S400C. The only gun I've owned that would beat it out for accuracy was my Career 707 II...yes, Korean barrels are made of gold:) My Big Ed Tuned B51 .177 gets about 35 shots between 850-875fps with Crosman Heavies for around 17fpe. That is from a 1700psi fill, and refill at 1200psi. It ends up being around a pump stroke per shot, which is incredible. The B51 trigger is good, but not as good as my AA S400C or the trigger on my FX Black Widow. The trigger IS however much better than anything that will ever be done with the sloppy plastic Crosman 2260 trigger on the Discovery. I have felt some really well modded Crosman triggers, but usually by the time the pull weight is reduced they are pretty sloppy, creepy, and un-predictable....better than stock, but not great by a long shot. I'm not saying Crosman doesn't make a decent gun, I've owned a half dozen of them, and still own one way in the back of my closet, but they are good for what they cost and no better. The B51, once tuned correctly is a very good gun for the money. I personally wouldn't pour a bunch of money into modding a B51 when I could step up to a better gun for the same price, but a well tuned mostly stock B51 is well worth the cost.
Here's a 34 shot string from my B51, start fill 1700psi, end fill 1200psi:
(http://www.gatewaytoairguns.com/airguns/photos/get-photo.asp?photoid=1237)
And here's a picture of my AA S400C, hehe, only because I like showing it off:)
(http://www.gatewaytoairguns.com/airguns/photos/get-photo.asp?photoid=1419)
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Dan thanks for the info . I don't know if you have ever shot a Crosman with the lower link mod but it has no slop and it turns out very good really . But Scott did say the B was as good if not better than that so I know I would be happy with the Bam . I still think I will wait till the first of the year be for I do any thing . I have also been thinking of a 10 mm rifle . I thought about de tuning the Discovery and then buying some thing like the B 50 as well . The stock on the B 51 looks high . If you did not use a scope would it be a problem to the point the B 50 would be a better choice ? Marvin
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Marvin, the comb of regular B51 does seem high, but from what I read the LOP of B50 can be too much for many shooters. Thumbhole stock is much better in that regard. Never handled or shot one though, this is a second hand info.
Chris
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I've owned both the B50 and the B51. The B50 stock is made for overgrown lumberjacks, it does not fit any mortal men. I use medium rings on my B51 and have no problems, it is not high like the B26-2. Neither of these guns have open sights though, so you'll need a scope. I am 6' tall and I cut 1" off of my B50 stock, then reshaped the grip area and it was still the most awkward gun I've shot, including the TalonSS. It isn't just an LOP issue, it's also the length between the grip area and the trigger, you'd need huge hands for it to fit right. The B51 in contrast fits me really well with no modification, although I DID reshape the trigger itself because as issued they have a really nasty hook to them.
mine:
(http://i92.photobucket.com/albums/l16/DanoInTx/IMAG0004-11.jpg)
I also made a new bolt handle for my largish hands:
(http://i92.photobucket.com/albums/l16/DanoInTx/IMAG0001-13.jpg)
The Crosman triggers can be made better, but will never be great. When you do the pivot mods you ARE decreasing pull weight, but you are also increasing pull length, then you can use some strategic set screws to clean up some of the length, but then you have a fairly hair trigger that still isn't all that predictable. I did a really nice trigger job on a 2240 a few months back, it REALLY improved the trigger a bunch, but again it still wasn't a great trigger. The B51 has a good trigger also, not great, but pretty good and better with a little work. I have a 2260 in my closet that hasn't seen the light of day in over a year, maybe I'll try a little more trigger tuning and see what I come up with:)
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Well Dan I am glad you mentioned the no sights front or rear . I am going back to open or peep sights on my rifles so that just about takes the Bam out of the picture for now. Marvin
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Yeppers, both are scope only guns, although a handy machinest could easily make a brake with a sight post for the front and then you could use a dovetail mounting rear sight on the back. Heck, you could even tap a hole in the issued brake and put a threaded sight post up there, like a 5 minute job. I've been thinking of doing exactly that for my S400C for short range and indoor shooting during Winter.
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This is all very true Dan and I thank you . I will keep it on the list then . I am just trying to keep from buying more rifles than I have to . I have to watch the wallet very closely now that I am not working. And I like to shoot a lot and if I become rifle poor I will not be able to buy ammo . I have been thinking on saleing or trading my springers off to get different PCP's and pumper's since I fell hard into the dark and bought both a tank and compressor . Marvin
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John, which end of the hammer did you face off? Did you take that 2mm off the front or off the back? I want to get the best compromise of power, accuracy and shot count, with emphasis being on power with heavy Eun Jin pellets, and accuracy. I don't want the power as a substitute for accuracy. I want it for flatter trajectory and more killing power. I'd like to get consistent, maximum expansion with Crow Mags, and maximum range and penetration with Eun Jins. I bought mine to be a hunting rig, not a target rig, though target worthy accuracy would not be unwelcome.
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You could drill and tap the front barrel retainer for a shotgun bead sight and install a fiber optic front. Then install a rear sight on the barrel, or the receiver. I used a cheap Daisy dot sight on my B50 when I first got it, while waiting for my scope and rings to arrive.
I was thinking about installing a larger diameter barrel, and either dovetailing it for a front sight, Or mounting a B30 front sight on it, and then install a peep sight on the receiver. I have this sweet #4 Lee Enfield micrometer sight that would be sweet on the B50. Of course, if I use it, I will need to make the front sight adjustable for windage, or make the rear sight mount adjustable for windage. I've seriously thought about ordering front and rear sights for a B30 and install them on a larger diameter replacement barrel. Or maybe even order a B30 barrel also, and lap, recrown, and cryo treat it and install it on the B50, along with B30 sights. I've been thinking about installing iron sights on my B40, also.
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Marvin, you are my God!
Hey, can you move to harwood Maryland so I could use your compressor??????? I will let you shoot my B51....
Ah well, didn't think so.
I really like regulated PCPs, but the high pressures involved make them a tiring choice for a hand-pumper like myself. Been trying to work out the horse power and motor requirements for making a low RPM linear-stroke mechanism for my Hill pump, only wish I had a machine shop to build it in. I went to a gun show in Fredrick Maryland about 5-years ago and had a chance to buy a compressor for $900. Should-a, Could-a, but talked myself out of it - stupid, stupid, stupid...
I pump, I pump then I'll pump some more, hi ho, hi ho, hi ho, hi ho, h iho, hi ho.....
So, its either a souped-up Big Ed tuned B51 in 0.22 for me or an AoA BSA Super Ten, decisions, decisions...
Scott
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Yes my big bore likes its protein . Click on the specials tab Marvin
http://www.protecair.com/