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crooked stripe · New Member

I bought this used Crosman model RM377 .177 cal rifle. I called Crosman for a trigger upgrade and they said there wasn't one. I also see the rifle was made for Crosman by Mendoza. The rifle is very accurate when bench rested. The trigger is so hard to pull I am pulling off target. I have shot many rounds through it and can't seem to do better. I shoot a CZ 452, a Rossi 92 and a few pistols and am able to hold nice groups. I have searched the net pretty hard and can't come up with a trigger upgrade. Can anyone help? There must be a trigger fix somewhere. John

Slavia · Moderator

You're probably stuck with de-burring and smoothing the contact points, and maybe shimming it against side play. You could also try bending a new trigger spring from lighter wire. There aren't any upgrade parts that I am aware of. I added a "second stage" and overtravel limiter to my RM577, but it required massive fiddling:

http://www.airgunhome.com/agforum/viewtopic.php?t=2396&postdays=0&postorder=asc&start=60

Crosman stopped importing Mendozas in favor of the Chinese B18/B19 platform (Phantom, et. al.). About the time they switched there was a large product recall of their Mendoza guns, but your RM377 is not included:
http://www.consumeraffairs.com/recalls_03/crosman.html

Now Mendoza products are imported through a company called Air Venturi, and sold through Pyramydair (among others). Newer Mendozas have a split trigger, each piece with its own spring. (Has the "feel" of a two-stage trigger):

It may be a long shot, but you could contact Air Venturi and Pyramydair to see first if they have parts, and second if they fit your housing:
http://www.pyramydair.com/
http://www.airventuri.com/

Or you could try contacting the manufacturer directly. They make airguns, machine guns, and office supplies (I'm not making that up):
http://www.productosmendoza.com/2008/portada.php

AirGunEric · Site Admin

Just an 'FYI'- PyramydAir and Air Venturi are the same place- "Air Venturi" is a name they created to label some products and use as the "wholesale" arm of the business.

That being said, you are stuck with them, or you can perhaps try to contact Mendoza in Mexico yourself (speak Spanish?)- but PyramydAir seems to have been having lots of issues lately with QC of their internal processes and controlling product returns effectively the last while-so I'm thinking this may be too much for them and you are left with all DIY improvements or trying to get something from the factory.

cheez · Member

What about taking it to a competant gunsmith? I don't know much about airguns (yet) but I do know that a good smith can work wonders on a trigger on a powder burning rifle.

AirGunEric · Site Admin

How much do you want to spend on an old Mendoza? Other than the deburr/polish of the wear points, any further work is going to require some amount of fabrication of parts- so you may want to consider how much this rifle is worth (you may also want to investigate if you can get parts for it- i.e. seals and such, otherwise this could become an example of throwing good money after bad at some point).