GTA

All Springer/NP/PCP Air Gun Discussion General => European/Asian Air Gun Gates => China/Asian AirGun Gate => Topic started by: mtbdrew on February 09, 2016, 12:46:04 PM

Title: TF99 Trigger tune?
Post by: mtbdrew on February 09, 2016, 12:46:04 PM

After getting my XS46U the trigger on my TF99 is really needed some TLC. Been searching around for a guide but haven't been able to find one so far. Anyone done a trigger tune on their TF99? Any recommendations on how to lighten the pull?

Thanks
Andrew

Title: Re: TF99 Trigger tune?
Post by: Doug Wall on February 11, 2016, 08:34:04 AM

I did some work on mine. There's not too much that you can do. If you look at the link below, you'll find a picture of the trigger group. You'll see a little "V" shaped spring. This is the key. If you make a replacement spring (piano/music wire- hobby store) like this, but out of smaller wire with a couple of extra turns, you'll get a lighter trigger pull. If I remember correctly, I used 5 turns(instead of 3) of a wire about 2/3 the thickness of the original. My trigger pull is now about 2 lbs.
http://www.network54.com/Forum/113813/thread/1155358038/Need+TF-99+%28QB36-2%29+trigger+diagram (http://www.network54.com/Forum/113813/thread/1155358038/Need+TF-99+%28QB36-2%29+trigger+diagram)

Title: Re: TF99 Trigger tune?
Post by: mtbdrew on February 11, 2016, 08:58:16 AM

Quote from: Doug Wall on February 11, 2016, 08:34:04 AM

I did some work on mine. There's not too much that you can do. If you look at the link below, you'll find a picture of the trigger group. You'll see a little "V" shaped spring. This is the key. If you make a replacement spring (piano/music wire- hobby store) like this, but out of smaller wire with a couple of extra turns, you'll get a lighter trigger pull. If I remember correctly, I used 5 turns(instead of 3) of a wire about 2/3 the thickness of the original. My trigger pull is now about 2 lbs.
http://www.network54.com/Forum/113813/thread/1155358038/Need+TF-99+%28QB36-2%29+trigger+diagram (http://www.network54.com/Forum/113813/thread/1155358038/Need+TF-99+%28QB36-2%29+trigger+diagram)

Thanks Doug, I'll have to give this a go. The gun is very accurate with Air Arms 10.3grn super heavies put only when you are very careful with the trigger pull. If I can lighten and smooth this out the gun will be even better.

Title: Re: TF99 Trigger tune?
Post by: Doug Wall on February 11, 2016, 09:35:26 AM

I forgot to mention that I also added a trigger stop to get rid of the long after pull. I did this by cutting a little slot in the plastic trigger guard. Start it just behind the end of the trigger, and go backwards about 3/8". Put a small (#8, about 3/4") bolt in the slot, with the nut on the inside. Adjust it in the slot to be just behind the release point of the trigger. This doesn't interfere with the bear trap release behind the trigger.

Title: Re: TF99 Trigger tune?
Post by: lefteyeshot on February 12, 2016, 11:18:19 AM

I've got a TF97. Is the trigger the same as the 99?

Title: Re: TF99 Trigger tune?
Post by: steveiep on February 13, 2016, 06:24:08 AM

It also helps if you polish the piston around the area where the sear latches into place.
Also, both the upper & lower surfaces of the sear (made from metal leaf riveted together) can be smoothed out.
Please ensure you do not round off any edges or corners.

Title: Re: TF99 Trigger tune?
Post by: mtbdrew on March 08, 2016, 03:31:04 PM

Quote from: steveiep on February 13, 2016, 06:24:08 AM

It also helps if you polish the piston around the area where the sear latches into place.
Also, both the upper & lower surfaces of the sear (made from metal leaf riveted together) can be smoothed out.
Please ensure you do not round off any edges or corners.

Yep I will need to do that too as it is still stock.