Ive never shot or owned a Challenger but I find them interesting. I think ill have to hunt one down to play with. They are a nice looking gun in my opinion.
So on the challenger there are 2 springs pushing against the hammer. Is that right. I just got one of these for my daughter to shoot in 4-H. So far I am impressed with it. 125 shots 521-555 fps. Shot at all pressures and POI didnt seem to change. One hole accurate for the most part.
Quote from: Rivers3Plinker on February 18, 2016, 04:25:09 PMQuote from: Pellgunfun on February 18, 2016, 10:53:07 AMCan this thread be set as a "Sticky" or whatever ya call it?There is a wealth of good information in this thread, and I'd hate to see in get buried over time.Also I do have one question about this subject, and maybe it's already been asked already.Why not have the Hammer "linked" to the rod in some way?Oldpro Mrod SSG appears to be an example. Rod is threaded into the back of the hammer weight. Adds mass to the weight and nothing comes out the back of the gun.Actually the Mrod has a striker that is screwed into the hammer face and it is unscrewed ( that is a first for me ) and the threads drilled out then the striker is passed through the hammer and the spring with lock nut installed to preload the hammer spring and the rear plug is adjusted to allow .004 free travel from the striker to the valve pin with the rifle cocked
Quote from: Pellgunfun on February 18, 2016, 10:53:07 AMCan this thread be set as a "Sticky" or whatever ya call it?There is a wealth of good information in this thread, and I'd hate to see in get buried over time.Also I do have one question about this subject, and maybe it's already been asked already.Why not have the Hammer "linked" to the rod in some way?Oldpro Mrod SSG appears to be an example. Rod is threaded into the back of the hammer weight. Adds mass to the weight and nothing comes out the back of the gun.
Can this thread be set as a "Sticky" or whatever ya call it?There is a wealth of good information in this thread, and I'd hate to see in get buried over time.Also I do have one question about this subject, and maybe it's already been asked already.Why not have the Hammer "linked" to the rod in some way?
The spring on the transfer bar also pushing towards the front, tending to hold the valve open and increase the dwell....
Yes it is touching the valve stem all the time, it is spring loaded against it.... Since the valve lift in a Challenger would be very small (~0.060"), I would think it even touches it at full open.... Bob
I played around with the Hatsan today, and got the SSG working in it.... sort of.... First of all, here are the changes to the gun.... First the stock....You can see the recess ground in the top of the stock to miss the stop nut on the SSG.... This is a mirror image of the one in the rear plug, posted earlier.... Now the rear plug, with the SSG in place.... The gun is uncocked, all you can see is the stop nut and the O-ring, against the back of the plastic rear plug.... The guide rod passes through the existing hole in the middle of the plug....You will notice that I also had to grind a recess in the bottom of the safety button to miss the stop nut, as well as the rear plug.... I don't have a photo of the SSG out of the gun at the moment, but here is a view of the top of the tube and you can see the SSG inside.... The spring sits in it's original seat in the front of the rear plug....It consists of two 1.75" x 0.045" wire springs on a 3/16" guide, with a preload of 1.2" (almost 14 lbs !).... The cocking force peaks at nearly 19 lbs., but of course the side lever makes easy work of that.... Lastly, here is a photo of the gun reassembled, this is the cleanest possible installation, you can't even see the SSG....When I saw how much preload was on the original tube, I was concerned that I could come up with an SSG that would be able to launch the hammer hard enough to create the 72 FPE the gun was shooting before.... because the original spring preload of 9 turns (nearly 9 lbs.) would have been supplying a lot of the valve dwell.... Well, as it turns out, I was right.... I have only done one trial (and might actually give up on this SSG conversion), the results were a 21 shot string from 180 bar down to 120 bar, with 25.4 gr. JSB Kings from 952-979-941 fps.... That averaged 52.9 FPE, for a total of 1110 FPE from 14 CI x 60 bar = 840 CI of air total, which works out to 1.32 FPE/CI.... The closest comparable string I have with the original hammer spring setup, was with 5 turns of preload, from 171 bar to 120 bar, 16 shots averaging 52.8 FPE at an efficiency of 1.18 FPE/CI.... Both strings had a 4% ES and the same FPE, so they are roughly equivalent.... This means I have gained 31% more shots, at a 12% increase in efficiency.... However, there is no way with these springs in the SSG I will even come close to 72 FPE.... I have the setscrew in the hammer set right to the bottom, and adjusted the gap to a bare minimum (~ 0.020").... There is so much preload on the hammer spring that when cocked it is within about 1/16" of coil bind.... so there is nothing more available without using a stiffer spring.... At this point, I don't think it's worth it.... I will ponder it for a day or two, but this gun is probably going to return to normal.... The one thing I did accomplish, which I never managed before, was over 2 magazines with the JSB Kings at over 950 fps, so it's a decent setup.... just not the 72 FPE monster I know this gun can be....Bob
Is there any benefit to using a lightweight hammer with the SSG mod? or best to just use the hammer that would come with WAR's kit?
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