another 1377 trigger mod

Started by plinker99, March 24, 2013, 05:40:46 AM

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plinker99

   i got one of the amazon $39.00 specials.
   after doing the popular trigger mods, polishing contact surfaces, lighter spring, & lube, though lighter & easier to shoot, i still am jerking my shots.
    someone recomended the 1701 trigger group.  i did check on the 1701 trigger group.  looks good. but for me, it's a little too much to put into this pistol.

  so being the a real cheap (ecconomical)  i came up with one that i have not seen yet.
1) mod for the sear.  i welded about 1/8 of an inch to the trigger side of the sear to get a longer lever ratio.  i lost the safety ball so i don't know if the safety will still work with the longer sear.  i'll check that later.
2) 2nd mod for the sear.  i filed a little on the top of the sear that stops the upward travel a little to get more sear to hammer engagement.
3) mod for the trigger.  i epoxied a small chip of plastic in front of the hump that engages the sear to get a shorter lever ratio on the trigger.  the added plastic is really close to where the safety would lock the trigger.  eventually i'll check that and see if adjustments are needed for the safety to work.  with this setup, it might possible to make a 2 stage trigger.  i'll try that later.

   with these 3 mods,  i can now feel the sear movement before it fires.  before it was just like only a jerk.  the trigger pull now is slightly longer, but for me it's ok.

   i don't have a trigger pull scale, but the spring scale that i have measures about a 1lb. 2oz. pull to fire.

   i'll be interested in any comments on this mod.

Thanks,
plinker
plinker99

MichaelM

I was thinking something vvery similar to this but wss trying to figure out a way to fatten the rear of the trigger to add setscrews so I could adjust it for a 2 stage setup... I agree there is a lot of wasted leverage that could be used...

1377x

good job
have you seen these
this is only a drop in the bucket
many many triggers have been adapted in more ways than one
how does that saying go
there is more than one way to skin a cat ;)
no offense to you cat lovers :P
closed mouths dont get fed

quickster47 †

Well that is definitely thinking outside the box and if it works for you that is all that is important.

Good job.  :-*

Carl

Here is another mod you can do.  Add a 3/32" bearing to the top hump of the trigger for added smoothness.



I've never wanted something so useless in my life.
In Omnia Paratus
1947-05-19 - 2016-07-14 †

Flex

Quote from: quickster47 on March 24, 2013, 01:14:36 PM
Well that is definitely thinking outside the box and if it works for you that is all that is important.

Good job.  :-*

Carl

Here is another mod you can do.  Add a 3/32" bearing to the top hump of the trigger for added smoothness.
I agree with Carl in that you most certainly have stepped out ofthe box! But since you asked for comments... here goes. First off, I'm not so sure that disabling the safety is EVER a good idea. I know many here on this forum have done so and for certain situations, like if you always shoot alone, you'll probably be OK. There's bound to be a time though, that you'll be plinking with friends, your kids or grandkids and having a functional safety will be important. I'm just sayin'. Secondly, and I'll start with the fact that I'm neither a mechanical engineer nor a firearms designer, the general rule is "there's no such thing as a free lunch". Changing the lever arm ratios has reduced the force required but as you mentioned, increased the trigger pull length. I think the you further compounded this by increasing the engagement of the sear/hammer interface. Fortunately, at this point, there is no irreparable damage. Crosman sells the sear for $1.15 and the same (I think) for the trigger. The little steel ball (most of us have "misplaced" that little sucker) is also $1.15 but I bought 3 for a dollar at my local hardware store. It's just a 3/32" ball bearing. If you lost the spring too, Crosman has it for (wait for it) $1.15! There's a small spring inside of a BIC lighter that can be cut to fit. (Your "economicness" will appreciate that). While I don't necessarily think that the Crosman designers "detuned" the trigger on these entry level airguns, they certainly left room for improvement by merely smoothing and polishing the interface surfaces and pivot points. Most of us (including you) that like to tinker, have done all that and probably put in a lighter spring. I think that my next little enhancement will be the 3/32" ball placed in the top of the "hump" on the trigger arm (as described by Carl). Not only will that reduce the friction at that interface, it will compensate for the material removed from the contact surfaces on the sear when those areas are smoothed and polished. I'm working on a similar "friction reducer" at the other end of the sear where the trigger spring engages the sear. More on that later. Back to your mods. You've done some interesting tinkering and it seems like you've fixed the problem that you were experiencing. Kudos on that! The main issue I have is disabling the safety. Figure out a way to restore that function and I'd be totally cool with the whole deal. Strong work. Flex
Daisy Power Line 92
Crosman 781 Single-Pump rifle
Crosman Fury Break barrel springer
Crosman BackPacker 2289g
Crosman 1322c
Crosman 1377c
Crosman PowerMaster 760 SC
Crosman 1377 (2nd variant)
Crosman PumpMaster 760
Chinese B-3-? .177cal
Crosman 2240 (now .177 carbine hybrid)
Daisy 105 B
Crosman A*I*R 17 Single-Pump rifle (Phase I)
Crosman 140 .22cal rifle (Fourth Variant)
Black Ops "Exterminator" CO2  BB revolver
Chinese B 3-1 .22 cal
Bemjamin 132 .22 cal pump pistol
Hatsan TAC-BOSS 250XT CO2 BB pistol
Crosman 1008 RepeatAIR .177cal CO2 pellet pistol
Daisy 717 target pistol

breakfastchef

Two things that matter...

1) It works for you
2) The modifications are durable
Larry

dan_house

Plinker,
Welcome to the insanity....  ;)
I can only add that you get a smoother feel bypolishing the piece that the sear spring and sear interact with. Also polish the point in the frame that that bit rides on. If you havent (pics didnt show it) add some some shims to the trigger and sear to take the wobble out
Adding a trigger shoe will further reduce your perceived pull effort
I'll echo what every one else has said about the safety......

dan
dr_subsonic's pneumatic research lab
The lunatic fringe of American airgunning

Southwest Montana's Headquarters for airgunning supremacy

Member of the Western Heretic Alliance

plinker99

thanks to all who replied.  i've been tinkering with this some more.


  1) i got a bunch of parts delivered & slowly am trying them out.  the most promising is a 1701 trigger with the 2 adjustment screws.  i'm trying to see if i can get it to be a 2 stage trigger without all the other parts.
  2) yes i'm trying to restore the safety.  ball was in the parts i ordered.
  3) i did make some shims to take out the wobble in the trigger & sear.  i used the plastic blister package that the 1377 came in and a hole puncher.  seems to work ok.  i also epoxied the trigger pin & sear pin to the frame to get a solid mount.
  4) i noticed that the way the trigger is curved, my finger stays close to the top.  i filled in the curve with epoxy putty & now am filing it so my finger rides on the lower part of the trigger.  more leverage that way.
  5) i did stuff & shim the piston & trim the valve.  i tested for power & found that it is retaining air at 16 pumps.  i get 632 fps at 10 pumps, 701 at 15 pumps with rws basic 7.0 grain pellet.
     i usually shoot at 5 to 7 pumps, about 500 - 560 fps.  eventually i would like see if i can get that with 3 - 5 pumps.

more later.
plinker99

seagullplayer

That is some really good power in my book.
Crosman 1377 scope, laser, tactical light
Crosman 1322
Crosman 600
Crosman storm XL
Benjamin  titan 22
Daisy 15XT
Beeman P17
Crosman Trail NP Pistol
WRS 350 .177

Martin, Harley, Goldwing and Cub Cadet, ya I'm like that...

KevinP

Kevin
Albany, New York

Brent

Good to hear back from you plinker.

Some interesting new approaches you are taking. Very cool on the outcome from stuffing the piston and your valve work! Those are good numbers!!