No4 MK1 trigger would not make weight at Camp Perry........

[Peter Laidler]

That's useful to me JM as I'm doing it all from memory... What would be good is to have a high speed video (slowed down for slow motion of course) of the action taken from a skeletonised action. But we'll plough on......

If anyone wants to cull all this info and make it into one of those whatever you call them thinggies, then please feel free when it's all finished.

[jmoore]

Well, it's sort of a functional cutaway! Maybe this will tie the works together. You'll just have to imagine the trigger guard adjustments until someone else has something more useful.:

[Maxwell Smart]

JM could you tell us what factory that receiver in your "skeleton" photo is from?

I am interested because I've wondered if the "scoop" taken out of the receiver sidewall (on the sloping part, just to the rear of where a No 4T front pad might finish) is a common late-war thing, or peculiar to one factory (Fazakerley?)

[jmoore]

It's probably an unfinished Fazackerly. But it's a mystery in general. It was only shown because of the complete trigger assembly. There's an old thread all about it somewhere in the files.

If it's a distraction I can crop out the excess that's not trigger related!

[Maxwell Smart]

Thanks JM

The old thread is probably one of mine - I have a BSA FTR No 4 Mk 1/2 with just such a scoop, and believe it to be a late war Fazakerley-made rifle, FTR'ed in the mid 50's into the AXXXX serial range for client states unknown...

[Snafu]

7 & 1/3 turns from tight to the click of disengage of treads
Lock washer is there
when drawn down tight first stage does not always return when released.
Snug (just slack taken up ) seems OK and has both stages
With screw like this slot lines up with punch mark on trigger guard

I just read the follow up
That is next

[Peter Laidler]

Yep, it's usually about 7+ threads in my limited experience of these rifles. I haven't written the next bit yet! But if the trigger isn't returning after the first stage squeeze, then it should be! This is (?) caused by the sear nose not being rounded and/or the sear face of the cocking piece beinbg rough. It should be polished UP and DOWN and NOT across

If you've got both stages with a crisp and instantaneous 2nd pull, then you're 90% or the way. Hold on for a few days.......... we'll get5 there in the end

[Peter Laidler]

Sorry for the delay, but work and all that.......... If you're unhappy about thesecond pull breaking too sharply, you might just radius the lower humped bent VERY slightly to give it a bit more 'slack'

Anyway we're going to look at trigger pull off weights. To test the weight it is important to operate the trigger tester along the SAMP plane that the finger squeezes the trigger - that is along a line from the trigger extending to 3/4" or so behind the cocking piece when in the cocked position.

If the pull off in thefirst pull is between 3 to 4 pounds then it indicates that the sear spring is correct. What you need to do is to increase the angle of the cocking piece against the sear nose - the angle of attack - that will increase the drag and therefore the weight on the sear and therefore trigger as the sear is drawn down the face of the cocking piece.

You might find, for example, that the angle of the cocking piece from the bottom edge is, say 100 degrees (or 80 degrees from the top surface. New ones are pre-ground at 100 degrees.....) then you'll need to bring it down to, say 96 degrees.

Just take it very carefully with a fine oilstone, bit at a time. It won't take much to increase the pull-off weight.

Hope it all works well. But make sure that you've checked the operating weights of the striker spring first