CP1 Pistol Trigger PullApril 29 2017 at 10:52 AM
Kid Shelleen (Login Kid.Shelleen)
My CP1 Co2 Pistol has a 2.5lb trigger pull and I would like to try to get it closer to 1.5 to 1 lb. I’ve done some light polishing of the trigger and sear contact points, reduced the travel and lubed it, but can’t seem to find any posts on reducing the trigger pull weight. From what I can see the primary way would be to cut a little off the sear spring. Anyone have experience with this? Is it possible to get it down to 1.5 lbs and still function and be safe? I posted this question on another forum but haven't received a response yet and I'm kind of anxious to get it fixed.
Thanks for the help, Shelleen
|This message has been edited by Kid.Shelleen on Apr 29, 2017 11:22 AM|
Steve in NC
Is this the same CP-1 that, on the MrodAir website, is spec'd...
|April 29 2017, 12:27 PM |
...as having a trigger adjustable down to 8oz.?
Trigger Adjustable, 0.5-4 LBf
|April 29 2017, 1:03 PM |
Yes, I got it from MRod Air. The receiver is marked AIRMAX MRodAir Target Master .177 The accuracy is OK but the trigger pull was long and on the heavy side. I cleaned up the contact points on the sear and trigger and reduce the pull length by putting a spacer through the center pin that contacts the sear. There is a single grub screw that goes through the upper part of the trigger that contacts the sear but it is "frozen" in place and I don't want to take the chance of stripping the allen head out because it is very small. It looks like the grub screw only adjusts the length of pull so wouldn't help much to help reduce the weight of the pull which is now at about 2.5 lbs. From what I can see, reducing the length of the sear spring is about the only easy way of reducing the trigger pull weight. I was hoping someone else had this experience and successfully reduced the pull by shorting the sear spring a little. I'm reluctant to cut the spring since I don't have a replacement but if others have done it successfully, I'll give it a try.
not so much...
|April 29 2017, 3:10 PM |
The trigger/sear adjustment does more for reducing pretravel than it does for making the pull lighter. If the screw is adjusted to bear against the small cross pin and not against the sear, this will move the trigger rearward in the trigger guard. This helps because the guard is small/cramped to me, YMMV.
But to the point- use a lighter spring (I found one in my spares, lord only knows what it came from) and polish the mating surfaces. I have a safe, reliable trigger at 15 ounces that passes drop test. Some info here
You will still have a ton of overtravel but that can be fixed if you install an adjustment for it.
ETA Trigger pull weight progression:
Mrodair CP-1M, as delivered, lube and pretravel adjustment only- 2lb 2oz
Lighter sear spring added- 1lb 4oz
Polished mating surfaces, same lighter spring- 15 oz
|This message has been edited by cobalt327 on Apr 29, 2017 4:10 PM|
|April 29 2017, 6:49 PM |
Thanks for the information Cobalt. Your article "Inside the MRod CP1" was great and the photography was excellent. My CP1 arrived with a heavy trigger pull over 3 lbs and very long travel. As I mentioned, the grub screw on my CP1 was locked up solid. I'll try heating it up with a soldering iron and have another go at it when I have more time. Since I couldn't turn the grub screw, I put a small "roller Bearing" through the pin that the trigger sits on, which is similar to screwing the grub screw down further on that pin (Like they used to do with the awful triggers on the Benjamin Trail break barrel rifles. It significantly reduce the long travel of the trigger. It also moved the trigger back a little so there was more room in the trigger guard for my finger, just like you mentioned in your article.
I can't find a spring the correct size in my junk boxes so I'll try to find one at the hardware store tomorrow. If I can't find one that will work, I may try cutting a coil or two off the factory spring. If I can get my trigger down to around 1 to 1.5 lbs I'll be a happy camper.
Thanks again Cobalt for the information. I liked your article so much I saved it for future reference and sent a copy to my son who may be getting a CP1.
Glad it was of some use to you...
|April 29 2017, 7:23 PM |
I like that 'roller' you used, no reason it wouldn't perform well.
The trigger set screw is doused w/RED Loctite and that's why you're having a tough time removing it. I should have mentioned it in my original post. So it definitely will take heat- mine did- and I used the exact same method you mentioned, a soldering gun
in my case. In fact, if you look closely you can see a small spot of solder (circled below) that adhered during the heating of the set screw and trigger! Next time I have it apart I might remove it. Or not. ha
I have the grip off now, I don't like how it feels. Also have some stain coming. Hopefully I can whittle it down into something that feels better to me.
|April 29 2017, 10:13 PM |
I agree about the grips and am thinking about doing a little cutting and sanding but that will have to wait awhile until I get some more time. The first thing is to get a new sear spring then get that grub screw freed. I also want to polish everything up real good like you did. The grips will have to wait for last. I think a lot of us would be interested in seeing how your grips turn out. I hope you post photos of it.
I’m thinking something like this except less defined finger grooves then sanded down and stained a darker color like Walnut. Maybe cut some checkering before staining.
|April 30 2017, 11:53 AM |
I've found only a few photos of modified grips online. I'm going to take a lot of wood from the rear of the grip to 'stand up' the profile as much as possible- I just find the broken-wrist hold of the factory grip VERY unnatural. In the photo below you can just make out the lines from a pattern I made from a Ruger Mark .22. The Ruger has about the most laid-back angle of any grips I have, and like. So I figured patterning the angle to the Ruger grips might make the CP-1M more comfortable. I expect to do a LOT of trial fitting before I'm done but I believe it will be well worth it.
Here's one a fellow did down below this post:
This is from GTA:
|John Thomas in Spokane|
Grips-Here's an older post of what I did with mine,
|April 30 2017, 2:52 PM |
|May 2 2017, 10:47 PM |
Thanks for the two grip ideas Cobalt. I'm still looking forward to seeing what you do with yours. John, I'm also thinking of doing something similar to what you did. I was thinking of whittling my grips down similar to the first example I posted but since there is hardly any grain on the wood, I was thinking of using some textured paint that would give it a little grip. I also like Cobalt's idea af reshaping it to change the angle a little. I'm more comfortable with a less severe angle that put the barrel closer in line with the radial bone of my forearm.
|May 3 2017, 8:35 PM |
I'm sure you've heard of using bedliner spray coating for gun stocks and grips. I've never tried it but some people swear by it and I'd have to believe it would be better than something smooth like Plasti-Dip.
I haven't started on mine but as soon as I clear a few projects out of the way, I'm definitely going to have a go at it.
|John Thomas in Spokane|
I used Dupli-color rattle can bedliner as a base coat, and
|May 4 2017, 12:20 AM |
then the the black rattle can Plasti-Dip on top of that, with clear rattle can Plasti-Dip as a top coat. The end result was very similar to a Houge over-molded rifle stock, and the bedliner provides plenty of texture.
I normally just use bedliner, the Plasti-Dip was a spur of the moment thing, I had picked some up on impulse at the paint store when it was first introduced in a aerosol spray can.
The bedliner alone, or with clear coat is easy to use on wood, covers well, and is pretty tough after it's cured. I normally use it on stocks and grips that have poor grain, extensive repairs or a lot of filler, etc. that would look bad with stain or oil finishes. I've used it on quite a few things, including plastic and fiberglass.
I wasn't happy with the Dupli-Color, and won't be using it again. It sprayed on nicely and covered well, but needed too much prep work for the end result. It took three tries before it stopped peeling off. (I don't normally mind the prep work, I paint my own vehicles, and was a house painter for years.)
So Which Brand of Bedliner?
|May 4 2017, 2:15 PM |
Thanks for the information John. If I'm understanding correctly, you are saying "bedliner alone or with a clear coat is easy." If you no longer like the Dupli-Color spray on bedliner, what spray on bedliner do you recommend? I think I'm going to give this a try.
Re: So Which Brand of Bedliner?
|May 4 2017, 3:02 PM |
My first impulse is to say 'Herculiner', mainly because that's the one I'm most familiar with from advertising. And it has been around about the longest and it's available as a spray can. Another possibility is Rustoleum brand, again because of brand recognition. Also available as a rattle can. There are others, but I believe those two would be my picks- realizing I don't have any first hand w/any of them. All that said, I don't know how much my theory of brand recognition will hold up, seeing as how Dupli-Color is a well known brand as well! I suppose in the end you pays your money and takes your chances.
|John Thomas in Spokane|
Sorry guys, my wife tells me I'm not always the clearest person
|May 5 2017, 12:40 AM |
when it comes to writing.
I actually still use the Dupli-Color bedliner, it's the spray on Plasti-Dip
that I tried as a top coat and a clear that I didn't like.
The bedliner I use is Dupli-Color Bed Armor truck bed liner, I get it at an auto parts store in a 16.5oz spray can. http://contentinfo.autozone.com/znetcs/product-info/en/US/dup/BAA2010/image/4/
I've never tried any of the other brands, but they likely work fine also.
When I'm doing a wood stock or grips with the Dupli-Color I usually don't use primer, I strip the old finish and do any shaping or filling needed, then lightly sand with 80, 100, and 120 grit sand paper, then back to 100, and occasionally 80 grit again. The goal isn't to get rid of all the imperfections, just the big ones, and to knock down any filler and get a uniform appearance. The bedliner usually does a pretty good job of filling small stuff.
The wood should be slightly rough to the touch when you run your hand over it, but not enough to catch threads on a smooth dry cloth. If it's to smooth the bedliner can peel. Then I blow it off with a compressor and wipe it all down with a dry cotton cloth (old T-shirts work well), then start coating it with the bedliner. I usually let mine cure for a week or so before I put the gun back together, I don't know if it needs that long, it's just a personal preference.
If I do end up needing a primer I've had good luck just using the clear adhesion promoter in the rattle can. I don't usually clear coat it but it's done the same as any thing else that gets clear.
Metal can be rough sanded/primed, or both, and plastic and fiberglass work with the adhesion promoter.
I've done several sets of plasic grips and have been happy with them also.
Hopefully this is understandable, if not let me know. The only air rifle I still have that I did this way is one of my QB AR2078's, I have to dig the camera out tomorrow anyway so I'll get a picture of it posted tomorrow.
Re: Sorry guys, my wife tells me I'm not always the clearest person
|May 5 2017, 7:35 PM |
That's my mistake, I confused Dupli-Color and Plasti-Dip. So if you like the Dupli-Color bedliner, that's good enough for me! Thanks for the rundown of how to best use it for this application, too.
Trigger spring replacement
|May 6 2017, 9:21 PM |
The trigger spring is very small and hard to find. I ended up using the spring from a tire valve stem which was almost the exact size but much lighter. I use a pair of side cutters to open up the valve stems ends to remove this small spring. After polishing the mating surfaces and adding the new spring I was able to adjust the release to 1 pound which was too light so I now have it adjusted to a very smooth 1.5 pounds. Bob
|This message has been edited by bpratl on May 7, 2017 6:05 AM|
|May 7 2017, 6:36 PM |
Thanks to all for the great ideas. Thanks John for the clarification and the links. Very helpful. Bob, thanks for the information on the spring from a tire valve. I'll have the local tire store save me a few from their old tires and have a look at them. I actually got brave and cut about a coil and a half off the stock spring which brought it down to 1.5 lbs. That and the "roller" shim I put in to reduce the travel has made the trigger closer to what I was looking for. Next is reshaping the grips and deciding on a finish but that will have to wait for a while. Too many other things going on. My FX Streamline just came on Friday (had to wait four months for delivery) and I'm expecting a MRODAIR AIRMAX PRECISION MK II (SPA PP700) by the end of the week. Too many toys to play with.
AIRMAX PRECISION MK II
|May 8 2017, 12:21 PM |
I'd like to hear your opinion when you get it. I know there are gonna be a lot of happy folks when they're delivered (and I hope you all STAY happy)!
SPA CP1 2-stage trigger mod
|May 12 2017, 8:48 AM |