Set Trigger Repair - Investarms Hawken

[JohnnM257]

Yes the rear set trigger seems to set itself when I cock the hammer.

 

[Ed C.]

Hello I'm a complete newbie, & just bought the Investarms 50cal percussion 120B Hawken Rifle. From Dixie Gun Works, They sell it as the Dixie Hawken. I put it together about 10 minutes ago, & the rear set trigger seems to be always set when cocked. The front trigger pull, is about 2lb pull, when cocked which is perfect. I don't want to mess up the front trigger pull, but I would like my rear set trigger to function properly. So is the screw in the trigger housing, how I would adjust the rear set trigger, to work properly?

I'd remove the trigger assembly and start from the beginning going through the three adjustments needed. Three screws to adjust on trigger assembly. The internal screw on the large flat spring will adjust the pull needed to set the rear trigger. It must be loose enough to be able to pull the rear trigger but tight enough to trip the sear on the lock when the front trigger is pulled. The next screw forward of that located externally is a fine adjustment to that spring. Screw it in and it will lighten the pull on the rear (set) trigger but again you must be sure it will trip the sear. The third screw located externally between the triggers will determine the the amount of travel of the front trigger needed to fire the gun. Screw it in for less travel. Sometimes the manufactures will purposely make that screw too short to take full advantage of having a very light front trigger for liability reasons. You may have to replace it with a longer screw to get a true hair trigger pull. Once you find your setting use some wicking type (green) loctite to hold it in place. Or whatever else you choose to secure it.

 

[JohnnM257]

I'd remove the trigger assembly and start from the beginning going through the three adjustments needed. Three screws to adjust on trigger assembly. The internal screw on the large flat spring will adjust the pull needed to set the rear trigger. It must be loose enough to be able to pull the rear trigger but tight enough to trip the sear on the lock when the front trigger is pulled. The next screw forward of that located externally is a fine adjustment to that spring. Screw it in and it will lighten the pull on the rear (set) trigger but again you must be sure it will trip the sear. The third screw located externally between the triggers will determine the the amount of travel of the front trigger needed to fire the gun. Screw it in for less travel. Sometimes the manufactures will purposely make that screw too short to take full advantage of having a very light front trigger for liability reasons. You may have to replace it with a longer screw to get a true hair trigger pull. Once you find your setting use some wicking type (green) loctite to hold it in place. Or whatever else you choose to secure it.

Thank you for the very thorough detailed explanation on how to fix my issue Ed, I appreciate it.

 

[Ed C.]

Thank you for the very thorough detailed explanation on how to fix my issue Ed, I appreciate it.

Very welcome. As a newbe I went through trigger problems with my Dixie Hawken.....nothing worked and I knew nothing. Set me on a sharp learning curve. I'm no expert but if I can help you with my limited knowledge I'll be glad to. You'd think a function check would be done before these guns are sent out.

 

[necchi]

The next screw forward of that located externally is a fine adjustment to that spring.

To my knowledge The Investarms models do not have that main spring backlash screw.
The only adjustments are the main spring (that's the big flat thing inside) tension/mounting screw and the one between the triggers for travel as you explained.
I think @JohnnM257 's trouble is that the main spring is too loose.
It's typical of the sear to overstep it's position while the hammer is pulled to full cock,, if the main spring is too loose to hold the rear trigger cam, it could drop into it's set position.
@JohnnM257, tighten that big screw that holds the flat spring in place,, just a bit,, a quarter turn or less should work,,
While you have the trigger set out, play with it, watch how it works. Look at how the rear cam's little notch "set's" into the front trigger. The screw between the triggers adjusts how much that notch connects with the front.
If you get the main spring tension set right, the rear trigger should be hard to "set",, you pulling against the spring,, it's the spring that drives the rear cam into the locks sear.
Good luck,

 

[JohnnM257]

To my knowledge The Investarms models do not have that main spring backlash screw.
The only adjustments are the main spring (that's the big flat thing inside) tension/mounting screw and the one between the triggers for travel as you explained.
I think @JohnnM257 's trouble is that the main spring is too loose.
It's typical of the sear to overstep it's position while the hammer is pulled to full cock,, if the main spring is too loose to hold the rear trigger cam, it could drop into it's set position.
@JohnnM257, tighten that big screw that holds the flat spring in place,, just a bit,, a quarter turn or less should work,,
While you have the trigger set out, play with it, watch how it works. Look at how the rear cam's little notch "set's" into the front trigger. The screw between the triggers adjusts how much that notch connects with the front.
If you get the main spring tension set right, the rear trigger should be hard to "set",, you pulling against the spring,, it's the spring that drives the rear cam into the locks sear.
Good luck,

Thank you guys for all the help, with my trigger issue. I really appreciate everything.

 

[Ed C.]

To my knowledge The Investarms models do not have that main spring backlash screw.
The only adjustments are the main spring (that's the big flat thing inside) tension/mounting screw and the one between the triggers for travel as you explained.
I think @JohnnM257 's trouble is that the main spring is too loose.
It's typical of the sear to overstep it's position while the hammer is pulled to full cock,, if the main spring is too loose to hold the rear trigger cam, it could drop into it's set position.
@JohnnM257, tighten that big screw that holds the flat spring in place,, just a bit,, a quarter turn or less should work,,
While you have the trigger set out, play with it, watch how it works. Look at how the rear cam's little notch "set's" into the front trigger. The screw between the triggers adjusts how much that notch connects with the front.
If you get the main spring tension set right, the rear trigger should be hard to "set",, you pulling against the spring,, it's the spring that drives the rear cam into the locks sear.
Good luck,

The fine tuning screw on the mainspring is easy to overlook. It is that tiny screw just in back of the rear (set) trigger and is hidden when the trigger guard is in place. Both of my .50 cal. Investarms Hawkens have it. I do agree with your assessment and advice on the problem.

 

[TDM]

@Ed C. has it correct. See the post I made for this problem.
Post in thread 'New Investarms'
New Investarms

 

[necchi]

Honestly that's very interesting.
Can either you or @Ed C. share a side view photo of that trigger mechanism or one that demonstrates the Investarms trigger with that screw.
I've never seen one. Are they "new"?

p.s. didn't know about the double ? postings

 

[Ed C.]

Honestly that's very interesting.
Can either you or @Ed C. share a side view photo of that trigger mechanism or one that demonstrates the Investarms trigger with that screw.
I've never seen one. Are they "new"?

p.s. didn't know about the double ? postings

Investarm™ Bridger Hawken Replacement Trigger Assembly - Fits Investarm, Lyman & Cabela's models - IA257 See if this link works. It shows how that screw acts on the spring.

 

[7of7]

I remember playing with the sets on my rifle,… and got it set up to what I like. I played with all the screws for hours.. just figuring out what each screw did. Now, I don’t mess with them..(forgot what each screw did)

 

[necchi]

I'll be darned
Thank you @Ed C.
It's actually good to see the Italians step up to adding that screw

 

[necchi]

I played with all the screws for hours.. just figuring out what each screw did.

Yeah that can be tough, and hard to explain when making a post about the adjustment.
That backlash/spring travel screw can be key to making a crisp-fast response. It allows you to keep the mainspring tension high, but still off the rear cam.
If the spring is too tight and the travel screw too far out, it can force the rear cam too high pressing into the sear arm and there's cocking issues.
It's a fine balance,,