GTA
Airguns by Make and Model => Benjamin Airguns => Topic started by: Cslinger on November 29, 2021, 04:34:56 PM
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So I did some work on a Crosman MTR77NP and apparently I have no idea how to reinstall the trigger pack. I get it re-assembled but cannot get the gun to cock/engage a sear.
How do you put the trigger pack back in a standard Crosman NP gun (I assume they are all largely the same)
Apparently the hammer and foul language is not working and I am a bit frustrated. I am not completely mechanically inept so it’s extra frustrating. Ok I am mostly inept but I digress.
Thanks all.
Signed
Searless in Seattle :)
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If it's anything like the other Crosman triggers I've worked on, the sear on the top of the trigger pack has to be OUTSIDE the compression tube.
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The 77 trigger is the same as the optima or Vantage and most Crosman and Benjamin break barrels.
I don't know but maybe this is your problem. Looking at the trigger pack one part stick out toward the front. Sticking up from that part is a short part. That is the part that catches the piston when cocked. That piece sticks up inside the receiver. You kind of rotate the trigger pack into the receiver. The small part of the slot that is narrower, the part points forward has to stay outside the receiver.
What I do is use a little plastic grocery store discount card off my key chain and electrical tape to cover that narrow slot. That holds the part outside the receiver. After the trigger is installed remove the tape and the little plastic card.
Hope that makes sense.
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Been there done that, thiink it is right then it slips past , then no go, helps to have something to retain it on the install for sure.
(https://www.gatewaytoairguns.org/GTA/MGalleryItem.php?id=5438)
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This is a common problem. Drawings here are for a Hatsan Striker/Edge trigger group, but they are very similar to the Crosman trigger group.
Good installation / Bad installation
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Thanks all. I will tear back down and look but I could swear that is how I mounted it.
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Cslinger, did you install a longer spring or top hat or washers, anything to keep the piston from going back far enough to catch the sear. If not something in the trigger is not pushing the sear up to catch the piston or the sear is up inside the receiver.
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Nope. Just vanilla re-assembly. I haven’t had a chance to tear back apart to look at yet. Hope to do so today. Honestly it’s a crappy gun and I don’t know why I am putting the effort in. Dog with a bone I guess. :)
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I am throwing in the towel for the time being. I have had this thing apart several times today and IT IS assembled properly as far as I can see via info hear, parts diagrams etc. Best I can figure is the sear is worn down or something. Gun cocks, has "spring/gas ram" tension, completes its travel and simply will not lock. I will save it for a rainy day project at some point. It's such trashy gun overall in genetal that it's just not worth the effort or frustration beyond "dog with a bone".
At any rate, thanks all and if I get a bug to tackle it in the future and get it up and running I will try to remember to respond to this to close the loop.
Take care, shoot safe,
Chris
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Out of curiosity, did you adjust the trigger? Could be you went too far.
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Not intentionally so. I do have a CDT trigger in the gun but it has worked from day one and never been adjusted. That thought did cross my mind but like I said I didn’t dork with the trigger at all at least intentionally and I am not sure how I could have done so unintentionally.
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Before you get totally po'd & trash it, send it my way. I'll sort it out, for you. No charge.
It's got to be something simple, that's overlooked.
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Sometimes I need to set things aside for a while myself. The B19 platform is what it is, don't get too discouraged. While not difficult to assemble/disassemble, there are parts that can give issues. If you need any parts, send me a PM, I have lightly used spares.
I'm going to include some photos for reference. Lots of focus on the trigger assembly, but is the piston oriented so the cocking shoe drops into the proper slot?
(I may have missed aligned things once or twice... ::) ;D )
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Followup and the reason why I don't buy Chinese guns or Crosman in general.
So I tinkered with the gun a bit more and got the sear to catch. I guess I just didn't have it "JUST RIGHT" but in doing so I found the root cause that started this whole mess.
Quick back story. The gun has never shot particularly well. So I spent time off and on doing the normal stuff (stock screws, ammo types, learning the gun/holds, scopes etc. etc.) and never got the gun to shoot well. I am NOT a marksman but have been doing this long enough that I finally decided there must be a seal issue of some kind. I ordered breach and piston seals from Crosman.
I tore gun down, cleaned up, degreased, regreased etc. etc. put new piston seal on, which lead me to my current trigger issue.
So today..........being a dog with a bone.......I tore it down one more time and this time took it all down just to make sure I didn't have some minor geometry issue. In doing so and paying much closer attention to everything I found my new / unfired piston seal was already developing the same issue as the old one. I checked the tube for issues on insertion and there were none.
What I found was the "inside breach face" basically where the forks are pressed/welded/whatever to the compression tube was completely rough and jacked up with a divit/bend/chunk missing or some such on the edge which was causing the piston seal problems.
So I call Crosman and ....................THEY WERE ABSOLUTELY NO HELP AT ALL. Gun is out of print, no parts available, will not warranty for another gun. Fine, like I said gun was trash anyway and wasn't super expensive and I tore it down myself so they are absolved of all sins etc. I should have just sent it back to them to deal with whenever I got frustrated and determined a seal issue. So my fault.
All that said I have owned exactly 2 Chinese made guns and both were absolute TRASH.....there will be no third time and I certainly will not be buying any more Crosman products beyond pellets.
While I am fault for tearing the gun down instead of sending to them it would have been nice to provide some kind of olive branch. "Hey we will give you 10-20% off a product of your choice or some such" but not to be.
Now silver linings, lemons to lemonaid etc. at least I don't have to waste my time and ammo with it any more, I can simply bury this bone. :D