My 99% complete custom 2240...

[eyebull]

...because a 2240 is never 100% complete...

But this is very close to what I want! It's taken me a few years to get here, but I finally have the semi-serious target pistol that I wanted to build.
The only original parts left on this are the foresight, gas tube, end caps, and the valve (though this has been tinkered with). Like nearly all custom 2240s. it's completely uneconomical and I could have just bought a proper target pistol for the money I have spent on this, but where would the fun be in that??

Parts list for the interested:
Globe ring for front sight from alliance hobby.
.177 barrel from a member on here, or the UBC - it's been a while!
Left handed .177 breech with hollow probe, from Gmac.
Trigger unit and grip, from Crosmods (fantastic trigger, awful company to deal with)
LPA MIM rear sight.
Valve and hammer springs have been balanced, with a top hat and spring guide for the hammer spring made from an allen screw and an empty .22 rf cartridge.

It gets about 35+ shots at about 5ft/lb.

http://imgur.com/a/nH5el

[gingernut]

Excellent.
Looks purposeful.

[AC all day]

Oooooh i want one of those trigger units!!!
Looks a lovely job there...well done

[ETCHY]

Very cool thing

[tim56]

Very nice too. I have a standard one apart from the trigger which i improved slightly by replacing the trigger packing spring washer with shim stock. Will
never be super accurate but a delightful pistol to use for plinking and playing with in the garden/garage. Tim

[eyebull]

Cheers guys

Oooooh i want one of those trigger units!!!

The trigger makes it, and really helps the extract that accuracy potential from the 2240.
It's just a shame that the guy who made it thought customer service and communication were alien concepts. His website is still up but I'm not sure he's trading anymore. Even if he is, expect to wait some months before dispatch, without having your emails answered. I was by no means the only person to experience this.
Can't recommend it for that reason alone sadly.

[harvey_s]

Hi
When I read your shot count I thought that doesn't sound like a lot...and I remembered something I read by a gent named Al Stone who once made a nice heavily modified 2240 and I dug up one of his posts for you...

In standard form a UK 2240 puts out around 450 fps / 5.3 flb with a 12grain .22 pellet with a 7” barrel, if you change the barrel over to a .177 10” barrel you will get around 550 fps / 5.5 flb with a .177 8.2 grain pellet, now this is pretty wasteful in Co2 as quite a bit just blows out of the barrel, and a low shot count around 40-50 per capsule plus an erratic shot string. If you do go down this road you would be better cutting two turn off the standard hammer spring which will bring the fps to around 525 fps / 5 flb, this will give you a virtual flat shot string with 60-70 shots per capsule, these figures are all at 60*F, so you will have a good margin for safety . If you can get the balance right the fps/flb will not vary much between 50*F and 70*f and still keep you below the 6lb limit.

http://i154.photobucket.com/albums/s...Shot-Chart.jpg

I hope this is some help to your project

BTW if you are still using the standard Crosman trigger spring I can heartily recommend TR Robbs trigger spring kit which transformed my 2250XL.

[eyebull]

Thanks Harvey - I cannot actually make the hammer spring any weaker on this set up, as it wouldn't be able to pierce the CO2 cartridge! It is only just piercing it at the moment. I went through about 5 iterations of different spring/guide/top hat configurations before I settled on this one. It's just strong enough to set the trigger at half cock, and as far as I can tell there is very little hammer bounce when it is gassed. No farting noises

However I am currently making a Stopped Spring Guide (SSG) which user Gerard showed us a link to the other day (see the thread lower down, Crosmsn 2240 tune for more shot count), which apparently has had superb results with increasing shot count and consistency. Multiple people have managed to wrest the best part of 100 shots (!) from a single cartridge....The idea is that it has minus preload, so the spring runs around a guide that has a top hat built in so that at rest, it sits a mil or so away from the hammer. This is said to almost completely eliminate both hammer bounce and the power curve, giving 90+ consistent shots before dropping off rapidly.

So I'm in the middle of building one of these, and I've had an idea that will prevent it from being able to be turned up to beyond 6 ft/lb (always a risk with power adjusters) - I'm going to use a threaded rod, and braze a nut to the end that projects from the rear of the pistol. At the hammer end I will cut the end of the rod off when I have reached the perfect length, and loctite the stop nut. I'm also going to braze a tube on the outside of the rear plug to both act as a guide and to tidy it up a bit aesthetically.
I have another scrappy 2240 that I can test this all on before tearing this one down again.


I suspect it may be able to get a few more than 35 shots at the moment though, but that is as far as I have tested it at this stage. Those 35 (-ish, I wasn't taking notes) shots were at full power without noticeable drop-off. I'll be taking it up the range next week and making notes, and shooting semi-serious cards rested, so I can see exactly what it is capable of.
The trigger unit is all completely aftermarket and there are no crosman parts inside it. It's a pseudo two-stage but very crisp.

[harvey_s]

Thank you for that link...very interesting indeed.
It looks a bit Heath Robinson - but once you've​ found the best setting it would be very easy to remanufacture into something more discreet and I can think of a number of designs that would achieve the same result.

I would be very interested in your own findings if you get round to making one...this is turning out to be a good thread

[eyebull]

All I can say is WOW!!!!

First experiment today, took me about 5 mins to knock up an SSG at work. Allen bolt with the head on the outside with small o-ring under the head, nut on the inside, 4mm hole drilled through the rear plug. Maybe about 3/4 mm preload on the spring.

I didn't bring my combro with me so couldn't do any FPS tests, but over several hours, leaving at least 30 seconds between shots, it made at least 90 shots at near on full power, and then rapidly dropped off from #91 onwards. I took the gas out at #95.

The difference was immediately apparent, as the sound of the shot going off was noticeably 'snappier' and shorter, with no vibration evident. I also checked this with the rather unscientific method of resting the muzzle on the counter as I dry-fired, and there was no buzz as you normally get when you do this.

I am immensely pleased with how this turned out, and will be fitting the SSG to the pistol in the first post later on tonight, when I will also do some chrony tests.

[Tony.T]

Very interested in this- thanks!

[Hsing-ee]

That is an amazing custom job and taking some pretty daring risks with style.

It reminds me of the uber-upright Webley Self-Loading MK 1 pistol. Was the grip angle something of your own devising?

[eyebull]

Well, the results are in, and in my opinion are nothing short of PHENOMENAL.

If you don't believe it, I can understand, because I was there operating the Combro, and I still don't quite believe it....

I fitted the SSG to my target 2240, and with a little tweaking got the spring strength to the absolute minimum; it took two dry fires to pierce the CO2 cartridge.

This is the resulting shot-string. Each * is a dry-fire, which I did mostly in groups of five, chronoing every 5 or 10 shots as I saw fit. Figures are in metres per second as my Combro is a German model. The pellet used originally was an 8.4 grain AAF, until I ran out (!) and started using 8.44 grain JSBs - probably near on the same pellet TBH. I couldn't be arsed to wait 30 seconds between shots, so the dry fires were in quick succession. If you took 30 seconds between each shot, I suspect you could improve even on this shot count...

Two shots to confirm that the cartridge was well and truly pierced, and then:

***** ***** 103.4 100.7 101.3 103.8 102.6 ***** ***** 104.7 ***** ***** 102.2 ***** ***** 104.1 ***** ***** 101.8 ***** ***** 100.7 ***** 100.9 98.0 100.5 ***** 99.0 ***** 99.7 ***** 100.2 99.7 ***** 98.4 ***** 100.3 ***** (at this point switched to JSBs) 101.5 ***** 100.6 100.2 ***** 102.6 99.9 98.3 101 100.4 100.1 102.6 ***** 100.1 98.4 101.1 103.6 ***** 102.9 ***** 106.4 108.1 ***** 114.2 113.9 ***** 115.5 ***** 113.4 ***** ***** 91.1 (steady decline from here) 89.7 86.3 83.6 81.7 77.8 74.8 72 (dry fired from here as I didn't want a pellet stuck in the barrel) ***** ***** *****

I make that 208 shots from start to finish, with perhaps the last 25 not being useable. I'll settle for over 180 shots out of a single C02 cartridge though

As I said at the beginning, Phen-Bloody-Omenal.

Obviously this is less than half of the power it was set at originally, but for this kind of consistency and shotcount, and for a target pistol, I am very willing to lose some power.

Seriously, everyone that likes to tinker with Crosmans should do this mod if they do nothing else. It has completely transformed this gun IMO. It may even be -dare I say it! - 100% complete now...

I've added a couple of pictures of the SSG here. I'll do some more detailed pictures when I make the second one (because I'm putting these on all of my Crosmans )

[eyebull]

That is an amazing custom job and taking some pretty daring risks with style.

It reminds me of the uber-upright Webley Self-Loading MK 1 pistol. Was the grip angle something of your own devising?

Thanks

The grip and trigger block are as they came from Crosmods - the grip is more upright that I would like: I suspect it makes a bit more sense on a 2250 or stocked 2240. The other grip style they have is more AR-like, which is what inspired me to make my AR-style 2250. Now that that one is pretty much finished I may take some pictures at some point.

[harvey_s]

Whilst the shot count is impressive the set velocity is also quite low...at 100 m/s it probably won't punch clean holes at 10m.
I've never had a .177 co2 Crosman so I can't compare it to anything I've owed - but by way of comparison my Tau-7 is .177 and 12g co2 powered and at about 120 m/s it'll do just under 90 shots on a single cartridge.
I normally run it at about 150 m/s and it'll do around 70 shots to a cartridge.
It'll be interesting to see what it does when you wick it back up to the 5 ft/lb mark as the gun was doing previously as at the moment it's difficult to gauge the improvement in efficiency.
Keep up the good work....this is interesting stuff