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PostPosted: Thu Feb 18, 2016 8:26 pm 
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Joined: Tue Oct 13, 2009 1:27 am
Posts: 2514
Location: Vancouver
Oh man, do I ever have a long story to share... but I won't. I'll spare you guys for once. Basically the cheapness and compromises inherent in the Crosman platform led to my making a rash decision to 'upgrade' the bolt size... forgetting that a drill will track the easiest route in steel and of course boring out the bolt guide hole made it profoundly crooked, killed my steel breech. So I tore down the 2240 thinking to try the regulator in my 2260 and swap over a few other parts, the grip and longer barrel and scope. On opening up the HiPAC I found my Lane regulator wasn't actually doing anything any more. It did work for a long while, maybe 9 months, but lately velocities have been a bit of a struggle when trying to tune with an SSG in the 2240. Just couldn't figure out why. Well it's because something inside the regulator blew out and I can blow through it like a drinking straw. There goes $160 worth of hardware. Sometime I'll open it up, see whether it's just an O-ring or whatever... but for now I'm kind of put off by regulators if they can just fail like that without my knowing about it. I was running 3,000psi in the valve, not 800psi, no wonder things got difficult! No wonder I couldn't get an SSG (3 built, with numerous variations tested in each) to work properly.

So I've put the hammer and my latest 2240 SSG with really long range adjustment potential and a very long guide and spring into the 2260 and did some testing and adjusting. Managed 25 shots with JSB 14.35gr at 733fps average or 17fpe filling to 1,800psi and shooting down to 800psi, for an efficiency of 1.56fpe/ci, best so far with the 2260. That's with about a 16" barrel. Used a black delrin adjuster threaded to 0.5"-20tpi and tapped the steel rear cap the same, so there's abundant room for a slightly fatter spring.

Attachment:
SSG_hollow_delrin_adjuster.JPG
SSG_hollow_delrin_adjuster.JPG [ 37.12 KiB | Viewed 615 times ]


Used a carbide bit to bore the striker hollow slightly larger so there's no excess friction with the (slightly too snug for stock hammer) springs I ordered from an eBay seller - 8mm OD with 1mm wire thickness. This spring is just as easy to use as I expected, strong enough to give some kick but weak enough that I can put a fair bit of preload on it in a long SSG. Here's a string with 14.35gr pellets:
724 728 726 729 731 731 730 734 731 732 736 734 733 734 733 734 742 739 739 736 740 739 731 734 736
I can live with that. Especially since there's no regulator to worry about mysteriously failing on me. Shoots slightly better with the JSB Exact Heavy 18.13gr, going up to 17.5fpe, though with a bit more drop at distance. It'll do for the Mission FT meeting Sunday and until Rick gets healthy enough to make an adapter for my QB78's Ninja bottle. That barrel is crazy-accurate so I'm looking forward to shooting it in FT.


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PostPosted: Sun Feb 28, 2016 7:14 pm 
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Joined: Wed Sep 10, 2014 2:42 pm
Posts: 147
Location: Ontario
I have been working on an SSG for my .22 disco. When I first got it I was disappointed with the 14 or so usable shots. In the past I have tried with my diy PA and some porting of valve, thinning poppit, and different tport sizes to try to get over 20 shots with jsb 15.9 at 800-850fps. I am a rookie at this and nobody up in my area that I know doing this stuff so flying by the seat of my pants.This is just what I want for hunting small game. I have come close to it. I had drilled out my endcap long ago and threaded so I could change springs on the fly so Bob's first SSG was easy to adapt to. I tried Bob's first SSG 3inch and used my existing .040" thick springs in varying lengths but power dropped was first in mid 600fps. I made a new longer one and a couple of springs and even welded a 3/8 nut to the back of my endcap to be able to use the longer ssg before coil bind. I got back to 750fps and got a ton more shots. I am waiting on order for 10" long .312 springs n .037, .041. .047 and .055 for testing.

Here is the string I just shot jsb 15.9. almost at coil bind and small gap.

1 744
2 741
3 743
4 748
5 742
6 744
7 740
8 744
9 749
10 747
11 744
12 747
13 750
14 749
15 747
16 754
17 751
18 746
19 740
20 742
21 741
22 737
23 746
24 743
25 737
28 737
29 722
30 729
31 728
32 726
33 719

Not sure where to cut it off but I have never got near this many shots before the SSG.
Still want to get power back but this is a start. I made this really long bastardized SSG for testing and still ave the original 3" one. I am hoping to consolidate everything once I get new springs. I am sure I will get this shorter, but if I increase shot count dramatically and it sticks out the back, I will just make some sort of shroud for it.
Here is my bastardized version of SSG. It is under almost an inch of preload.

Image


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PostPosted: Sun Feb 28, 2016 7:15 pm 
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Joined: Wed Sep 10, 2014 2:42 pm
Posts: 147
Location: Ontario
Ok...I polished my hammer and hammer tube area to a mirror finish starting 320grit up to 1500 grit. I lubed with some powdered graphite I had. I also drilled out my endcap so no possible friction for SSG there. The 3/8 nut welded on endcap is holding SSG 3/8 bolt. I also drilled and tapped my valve to 10-32 and installed high tensile screws. Then I filled to 2300psi and shot first shot with no gap so SSG basically non existent...hit 930fps with 15.9 jsb and loud. I turned SSG so small gap and shot some shots and the turned in another half turn, refilled to 2300 and shot a string down to about 1000.
Here is that string.

1 – 758 11 – 759 21 – 758 31 – 747
2 – 747 12 – 761 22 – 755 32 – 750
3 – 749 13 – 752 23 – 756 33 – 745
4 – 754 14 – 755 24 – 757 34 – 743
5 – 753 15 – 762 25 – 758 35 – 735
6 – 756 16 – 762 26 – 759 36 – 735
7 – 755 17 – 765 27 – 758 37 – 730
8 – 759 18 – 761 28 – 755 38 – 726
9 – 761 19 – 757 29 – 753 39 – 721
10 – 759 20 – 761 30 - 756


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PostPosted: Sun Feb 28, 2016 7:52 pm 
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Joined: Sat Nov 03, 2007 4:19 pm
Posts: 8972
Location: Coalmont BC
Nice improvement.... :)

Bob

_________________
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsonal;
Too many! Springers, Pumpers, CO2, but I love my PCPs and developing them!
Proud Member of the 2000+fps Club!


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PostPosted: Tue Mar 01, 2016 12:24 pm 
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Joined: Tue Mar 12, 2013 1:35 pm
Posts: 875
Location: North Of Toronto
I getting to understand this mod,someone made me a SSG ...very nice guy in the forum,I added the spring.

The spring is almost 2.25" and .35 wire,so to start this off with the least preload,I guess I can try it as I have it setup in the pic!

Is the spring to long to start with?

Image

This should help me out a lot with using Hipacs

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Benjamin Discovery .22
Discovery 2240 Pistol .22
Crosman DPMS SBR
KWC 1911 Tac
Leapers UTG BB 3x12x32


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PostPosted: Tue Mar 01, 2016 12:52 pm 
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Joined: Sat Nov 03, 2007 4:19 pm
Posts: 8972
Location: Coalmont BC
Just visually, that spring looks in the ballpark to do what you want....

Bob

_________________
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsonal;
Too many! Springers, Pumpers, CO2, but I love my PCPs and developing them!
Proud Member of the 2000+fps Club!


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PostPosted: Tue Mar 01, 2016 1:04 pm 
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Joined: Tue Oct 13, 2009 1:27 am
Posts: 2514
Location: Vancouver
The only question is whether the end cap will let you pull the guide/spring back far enough to allow cocking, I guess. Depends on the model and how yours is set up. But I've found with the 22xx models that a considerably elongated end cap is necessary to get decent results. Extending an extra inch or more beyond stock. That, and a larger diameter adjustable hollow bolt. Going up to 1/2"x20tpi threading and about a 2" long hollowed delrin rod threaded to match really improved my efficiency, allowing a much longer spring. The hole for the spring inside the adjusting bolt needs to be big enough to clear the spring well, otherwise the spring tends to bind against the walls when rotated one way or the other depending on the spring winding direction.


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PostPosted: Tue Mar 01, 2016 1:13 pm 
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Location: North Of Toronto
I drilled out the end of the butt stock,I think it should be okay when cocking.I have a stock adapter on to

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Benjamin Discovery .22
Discovery 2240 Pistol .22
Crosman DPMS SBR
KWC 1911 Tac
Leapers UTG BB 3x12x32


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PostPosted: Tue Mar 01, 2016 1:19 pm 
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Joined: Tue Oct 13, 2009 1:27 am
Posts: 2514
Location: Vancouver
Well so long as there's room. Easiest is to just get the hammer all the way forward then measure the depth from the back of whatever plug/adapter you've got in place, then that number is handy to compare to whatever portion of the SSG is extending beyond that and the total length of the SSG rod. Here's the one I made for my 2240:

Image

Being this long gives me a lot of control for small changes in velocity. I've got a hollow pipe stock on the thing so there's no worry about how much is extended out from the back.


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PostPosted: Sat Mar 05, 2016 11:09 am 
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Joined: Wed Sep 14, 2005 8:47 pm
Posts: 1689
Location: 123 gun street Nova Scotia
got an idea i had to give this a try , figured id post it ,i have a couple guns in the building stages and id like to see how well a self contained one will work . only adjustable by adding shims ( if it needs more then 1/8 '').
as the gun is it is not finished and i have yet to try it with air in the gun , but i think it will work well . these are made from drill rod , takes about 5 lbs to compress , it will be for a regulated gun .
i built one from soft steel and have been snaping the spring out from full compression to see how long it will take to break , or deform . under a hammer load it would be way less .
Image


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PostPosted: Sat Mar 05, 2016 7:12 pm 
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Joined: Tue Oct 13, 2009 1:27 am
Posts: 2514
Location: Vancouver
I like it, except for the skew in the spring. Not sure what could be done there. So it's a telescoping guide, right? Very cool. Could you elaborate on how it is adjusted? I was trying to think of how I could do one on the outside, with thin tubes, but inside looks more practical. Very tidy.


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PostPosted: Sat Mar 05, 2016 7:23 pm 
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Joined: Wed Sep 14, 2005 8:47 pm
Posts: 1689
Location: 123 gun street Nova Scotia
no skew when it's in the hammer , the hammer becomes the outer front guild .
it only adjusts by adding a sleeve , about 1/8 '' can be done with the bolt that skrews in , but mostly it will be tested and a perfected spacer will be added .
tested it out in a qb78 today , :) worked awesome .


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PostPosted: Sat Mar 05, 2016 11:05 pm 
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Joined: Sat Nov 03, 2007 4:19 pm
Posts: 8972
Location: Coalmont BC
Yes, the hole in the hammer becomes a guide for the spring.... but I don't think that is a good thing.... The SSG requires that the hammer be in free-flight mode while opening the valve.... As such, any source of drag is not good, and could lead to less opening force and dwell.... and even inconsistencies in velocity.... I'm not saying that WILL happen, but if you experience those things, that is where I would look for a solution....

Bob

_________________
Dominion Marksman Silver Shield - 5890 x 6000 in 1976, and downhill ever since!
Airsonal;
Too many! Springers, Pumpers, CO2, but I love my PCPs and developing them!
Proud Member of the 2000+fps Club!


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PostPosted: Sat Mar 05, 2016 11:11 pm 
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Joined: Sat Mar 16, 2013 5:15 am
Posts: 3573
Location: Edmonton
Whitewolf wrote:
Just let me know the majority of flavour deer, moose, elk or bear. Sorry about your luck it'll be smoked, my choice and the cook rules...lmfao


And so it should be, and YUM YUM! But don't let Gippeto confuse you; Whitewolf doesn't make you eat in the garage! Well, at least I don't have to eat in the garage, Al. :mrgreen:


Last edited by Edmonton<500 on Sat Mar 05, 2016 11:17 pm, edited 1 time in total.

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PostPosted: Sat Mar 05, 2016 11:16 pm 
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Joined: Tue Oct 13, 2009 1:27 am
Posts: 2514
Location: Vancouver
For the stopped spring in my QB78 I elected to counterbore the rear steel block for a nut then peen the guide rod behind that nut. Once I got it tested and adjusted to my liking that is. I'll want to come up with a more adjustable solution at some point, as spring weakening will eventually cause velocity to drop. But for now it's working very consistently.

Image


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