S400 MPR FT - Trigger Adjustment

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Mtl_Biker
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Joined: Thu Jan 14, 2016 9:25 pm

S400 MPR FT - Trigger Adjustment

Sun Sep 18, 2016 2:56 pm

I'm having a bit of trouble with the trigger on my new (to me) S400 MPR FT rifle. Sometimes it seems as if there's no first stage and the gun fires when I barely touch it. Other times it feels just perfect.... obvious first stage and nice second. And yet other times taking up the pressure on the first stage and then releasing it leaves the trigger with no first stage feel at all.

I'm used to rifles that allow the trigger to be adjusted with it removed from the gun and/or the gun being able to be dry fired.

Can you offer any tips on how to properly adjust this trigger?

Thanks!
AA S510 Xtra FAC Ultimate Sprorter *CARBINE* .22
CZ200S "Green" .177
AA S400 MPR FT .177
Steyr EVO 10
Feinwerkbau 800 Evolution Top
Weihrauch HW50S .22
Benjamin Sheridan 397P
Stoeger X5 (Canadian version < 500 fps)
Crosman P1377 & P1322

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Mtl_Biker
Posts: 68
Joined: Thu Jan 14, 2016 9:25 pm

Re: S400 MPR FT - Trigger Adjustment

Sun Sep 18, 2016 3:56 pm

Further investigation shows that if I take up just about all the first stage and then release it, there's no longer any resistance on it at all. If I only partially take up the first stage and release, the resistance remains normal.

What could be causing this?
AA S510 Xtra FAC Ultimate Sprorter *CARBINE* .22
CZ200S "Green" .177
AA S400 MPR FT .177
Steyr EVO 10
Feinwerkbau 800 Evolution Top
Weihrauch HW50S .22
Benjamin Sheridan 397P
Stoeger X5 (Canadian version < 500 fps)
Crosman P1377 & P1322

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Roger5
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Joined: Sat Jul 25, 2015 8:04 am
Location: Hampton middlesex

Re: S400 MPR FT - Trigger Adjustment

Sun Sep 18, 2016 4:13 pm

Mtl_Biker wrote:I'm having a bit of trouble with the trigger on my new (to me) S400 MPR FT rifle. Sometimes it seems as if there's no first stage and the gun fires when I barely touch it. Other times it feels just perfect.... obvious first stage and nice second. And yet other times taking up the pressure on the first stage and then releasing it leaves the trigger with no first stage feel at all.

I'm used to rifles that allow the trigger to be adjusted with it removed from the gun and/or the gun being able to be dry fired.

Can you offer any tips on how to properly adjust this trigger?

Thanks!

Before you start adjusting anything, i would check to see if cover screws are over tightened. Rog

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Mtl_Biker
Posts: 68
Joined: Thu Jan 14, 2016 9:25 pm

Re: S400 MPR FT - Trigger Adjustment

Sun Sep 18, 2016 4:36 pm

Roger5 wrote:Before you start adjusting anything, i would check to see if cover screws are over tightened. Rog


Cover screws?
AA S510 Xtra FAC Ultimate Sprorter *CARBINE* .22
CZ200S "Green" .177
AA S400 MPR FT .177
Steyr EVO 10
Feinwerkbau 800 Evolution Top
Weihrauch HW50S .22
Benjamin Sheridan 397P
Stoeger X5 (Canadian version < 500 fps)
Crosman P1377 & P1322

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TenMetrePeter
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Location: Luton Beds UK

Re: S400 MPR FT - Trigger Adjustment

Sun Sep 18, 2016 4:41 pm

The plate covering the trigger sears.

I'd planned on changing my trigger cover screws with S/S allen screws instead of the slotted ones. Can anyone think of a reason not to, provided I don't overtighten?
(I've already changed the other mishmash of slotted and posidriv on the butt plate area)

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Roger5
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Joined: Sat Jul 25, 2015 8:04 am
Location: Hampton middlesex

Re: S400 MPR FT - Trigger Adjustment

Sun Sep 18, 2016 5:31 pm

TenMetrePeter wrote:The plate covering the trigger sears.

I'd planned on changing my trigger cover screws with S/S allen screws instead of the slotted ones. Can anyone think of a reason not to, provided I don't overtighten?
(I've already changed the other mishmash of slotted and posidriv on the butt plate area)

AirArms changed them to Allen screws, so don't see a problem, but like you say don't overtighten. Rog

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TenMetrePeter
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Location: Luton Beds UK

Re: S400 MPR FT - Trigger Adjustment

Wed Sep 28, 2016 5:43 pm

Roger5 wrote:
TenMetrePeter wrote:The plate covering the trigger sears.

I'd planned on changing my trigger cover screws with S/S allen screws instead of the slotted ones. Can anyone think of a reason not to, provided I don't overtighten?
(I've already changed the other mishmash of slotted and posidriv on the butt plate area)

AirArms changed them to Allen screws, so don't see a problem, but like you say don't overtighten. Rog


There was a fair amount of loctite in the threads that had to be cleaned out with another M3 screw (didnt need a tap) before the new screws would nip up the plate with a decent feel. I didnt loctite mine in. Does anyone?

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Roger5
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Re: S400 MPR FT - Trigger Adjustment

Wed Sep 28, 2016 5:58 pm

Doubt if anybody loctites them in, leastwise I wouldn't . Rog

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TenMetrePeter
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Joined: Wed Jun 29, 2016 5:40 pm
Location: Luton Beds UK

Re: S400 MPR FT - Trigger Adjustment

Wed Sep 28, 2016 6:29 pm

I was surprised AA did. Loctite on slot heads is a recipe for chewed up screws. Maybe I just chewed up my warranty!

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