Modding BSA Lightning XL trigger

[Hangtight]

Hello all,

new to the forum, and returning to air guns as a grown up (many) years after messing around with them during a misspent childhood!
I wasn't planning on buying a rifle, but I was offered an outstanding deal on a virtually brand new BSA Lightning XL SE GRT by a mate who had apparently misunderstood his wife when she said, "Do what the hell you like....". Good little rifle, and after a couple of weeks and a tin of pellets, I'd learned to stop fighting the recoil and could consistently hit a 3/4" target at 30 metres. I had also developed a hatred of the trigger. Too heavy and too inconsistent...just too agricultural. I was having to concentrate so much on the trigger that it was affecting my shooting to the point where I wasn't enjoying myself.
A bit of hunting round the net and I discovered that the only trigger modifications available, other than a bit of polishing, were for the Gamo range. One of which was the CDT GRT-4G from Charlie Da Tuna, for the new Gamo SAT trigger. Nothing for BSAs. Then somewhere I saw mentioned that the Lightning uses the SAT trigger. So not being able to leave anything alone, I pulled apart my nice new rifle to discover that the BSA trigger is mostly Gamo SAT, apart from the safety. And seeing as the BSA safety was the only other thing about the rifle that I didn't like, a plan has been hatched.
The idea is to convert the BSA safety from the nasty wobbly lever on the right hand side of the action to something similar the Gamo version, which is a neat little lever in front of the trigger, within the trigger guard, which will then allow the use of the Charlie Da Tuna trigger.
If anyone is interested, I'll be happy to post some pics as I go along.

[Ed J]

Hello all,

new to the forum, and returning to air guns as a grown up (many) years after messing around with them during a misspent childhood!
I wasn't planning on buying a rifle, but I was offered an outstanding deal on a virtually brand new BSA Lightning XL SE GRT by a mate who had apparently misunderstood his wife when she said, "Do what the hell you like....". Good little rifle, and after a couple of weeks and a tin of pellets, I'd learned to stop fighting the recoil and could consistently hit a 3/4" target at 30 metres. I had also developed a hatred of the trigger. Too heavy and too inconsistent...just too agricultural. I was having to concentrate so much on the trigger that it was affecting my shooting to the point where I wasn't enjoying myself.
A bit of hunting round the net and I discovered that the only trigger modifications available, other than a bit of polishing, were for the Gamo range. One of which was the CDT GRT-4G from Charlie Da Tuna, for the new Gamo SAT trigger. Nothing for BSAs. Then somewhere I saw mentioned that the Lightning uses the SAT trigger. So not being able to leave anything alone, I pulled apart my nice new rifle to discover that the BSA trigger is mostly Gamo SAT, apart from the safety. And seeing as the BSA safety was the only other thing about the rifle that I didn't like, a plan has been hatched.
The idea is to convert the BSA safety from the nasty wobbly lever on the right hand side of the action to something similar the Gamo version, which is a neat little lever in front of the trigger, within the trigger guard, which will then allow the use of the Charlie Da Tuna trigger.
If anyone is interested, I'll be happy to post some pics as I go along.

I'm interested. I had a lightning XL but could not get on with the trigger so sold it!

I had a Gamo Shadow for a bit with a GRT-III trigger and that was very good.

[bufo]

I have one of the new GRTs too and the trigger is the one thing that lets it down. I'd be interested to hear how you get on too.

[Gwylan]

The trigger is shite, try talking to Welsh Willy.

Gus

[Hangtight]

Ok the. Here goes!

The GRT has a separate pin that retains the ram, so the trigger assembly can be removed with out a spring compressor. Just carefully drive out the rearmost pin and the whole trigger block can be removed once the anti bear trap slide has been removed. Mechanically the only differences between the Gamo trigger and the BSA version are the little bit of plastic that is the safety, and the moulded trigger blade itself and then only the bit on the front which interfaces with the safety. This is simply due to them operating in different directions. If you could get hold of the Gamo bits they would fit straight in and you cold dispense with the BSA safety lever because now the safety is in front of the trigger. But Gamo SAT trigger spares seem impossible to get. So a couple of hours with a hacksaw and some files, and I've made a little aluminium blade that slots into the BSA safety.
http://i1211.photobucket.com/albums/...l/IMAG0577.jpg

http://i1211.photobucket.com/albums/...l/IMAG0578.jpg

The safety now operates with a satisfying 'snick' rather than the 'cocktail stick stirring porridge' of the original. I've yet to remove the original lever, but if retained it would work back to front with the GRT4 trigger.

http://i1211.photobucket.com/albums/...l/IMAG0568.jpg

Safety on:

http://i1211.photobucket.com/albums/...l/IMAG0572.jpg

Safety off:

http://i1211.photobucket.com/albums/...l/IMAG0571.jpg

Once the Charlie Da Tuna trigger arrives I'll be able to position a 2mm diameter pin through the bit of plastic that will jam under the front of trigger when the safety is on and clear when the safety is off, just like the Gamo. A smaller 1mm dia pin will go side to side through the plastic safety catch and the stub of the safety blade I've made locking then together. Doing it this way also means I can put it all back the way BSA intende if it all goes wrong!

As an aside, is there any way of putting pics straight into a post, or is it links only?

[Shedder]

The trigger is shite, try talking to Welsh Willy.

Gus

Is that a technical term in welsh then?

[Aussiethunder]

I dont know if the trigger set up is different in the GRT to the standard lightnings but I'm currently in the middle of restoring and modding a lightning. I've taken out the 2 stage trigger( it's been polished) and replaced it with a older model trigger that is a straight pull (no little spring spring) I've ground 0.15mm of the end and ever so slightly changed the angle of the sear also I slightly bent the big spring to take a little tension out. The original trigger is to far back for my technique and trigger pull so I've welded a 4mm drill about 10mm forward of the original trigger to make a straight trigger, I tested it today and when it's adjusted to it's lightness it is a hair trigger.. It is that light that I bumped it and it went off.. But 1 and a quarter turns of adjustment it is lovely, If I can borrow a set of fishing scales I'll test it. when we get a laptop I'll post some pics.
I also put a blob of weld on the back of the saftey latch, then ground and polished the weld blob till I was happy with the amount of pressure needed to flick the saftey on and off ( no more wobbly saftey latch)
It did takes ages with alot of trail and error to get it to this stage..

[junglie]

I found shimming the side play out of them & de-burring & polishing helps a lot & correct adjustment. Every one I've worked on has had the adjuster allen screw wound right in which makes a bad trigger even worse. I actually shot one of my best 10 shot 15m groups with opens using an old tatty brum built supersport I'd tuned the trigger on.

[Hangtight]

This is what's going in instead of the nasty plastic item.

http://charliedatuna.com/GRT-4G.htm

It should bring the pull weight down from about 5lb to 1 1/2lb or so, as well as improving the break.

[hwtyger]

Weird, I had a spring Lightning XL, about 6 months old now, and it had a very good trigger. No need for any fiddling.
Dunno wether BSA uses the Gamo trigger. Mine didnt, very obvious.

[Gwylan]

Weird, I had a spring Lightning XL, about 6 months old now, and it had a very good trigger. No need for any fiddling.
Dunno wether BSA uses the Gamo trigger. Mine didnt, very obvious.

Perhaps I'm being a bit harsh, the newer ones are better, just not as good as the Rekord, or CD.

Gus

[POK!]

This new trigger is essentially the old Gamo trigger in a new chassis, that's why with minor modification or removal of safety the CDT type trigger upgrades drop right in.

[sbd]

...of all, welcome Hangtight excellent first posts, I suspect you are a prime candidate for "getting the bug" and joining our band of inveterate fiddlers... sorry "tuners" BTW have you tried adjusting the trigger weight?

At a slight tangent, on the BSA Supersport which is a forerunner of the Lightening and pre Gamo there's a mod you can do that converts the single stage unit to a faux two stage. I'm not 100% sure but I think it's as blade replacement from the Goldstar range, mine was done by SFS for the grand sum of £9. It's not a Rekord but it's quite good

[POK!]

It's sear overlap that's responsible for the long trigger pull in both Gamo and original Supersport triggers. If it's very long as in all Gamo and some BSA it can't be polished out IME, you have to grind the sear to reduce engagement. If your BSA has a little creep polishing can help. A wonky chassis and overtightening the rear stock screw can also introduce some creep on older BSA's. Installing a CDT blade on a new Lightning will give you a true 2stage fully adjustable trigger that will probably be better than the very best old style BSA.

[Hangtight]

As POK mentioned, the sear overlap is quite large so there is quite a lot of slightly rough metal to drag over more slightly rough metal under enormous pressure, with a slightly shonky piece of plastic before anything happens. I did try adjusting the trigger 'weight', but all the adjustment screw does is move the primary sear closer to the point of disengagement, so by the time you're getting close to a nice clean break the trigger is becoming unsafe. I did try one that had been polished but it still felt vague, just somewhat less agricultural.
The positioning and action of the safety was something else I grew to dislike with use so the chance to kill two birds......that and I can't help fiddling!