Trigger Question on Mk 4

[Peter Laidler]

Surely I tell how to determine the length of the bushing in the article. It's not a fixed length per se but a length that is suiteble for YOUR fore-end on YOUR rifle against YOUR trigger guard.

But to be honest, while you COULD machine one up from scratch, at what point do pennies become uneconomic? If you don't want to go to the expense of two original new trigger and sear axis pins, there's a cheaper way to go. Get ONE PIN, cap, fore-end and cut that into two lengths. One for the trigger axis and one for the sear axis pin. It is the exact diameter and that way, one long pin will get you two short pins.

[villiers]

... and while you´re at it, you could convert it to a Mk. II with the trigger hung from the action. Then you´d free yourself of all those problems that stem from bent trigger guards, etc. etc. influencing the trigger pull.

[Norton1]

OK - I pulled the sear and trigger. Both pins are nice and firm. No movement on the sear pin and very little on the trigger pin. I believe the fit is quite nice. I checked the sear end where it interfaces with the striker knob and the sear was not as it should be. Again going off of the pictures and directions in the book on accurizing. So I got my Hard Arkansas stone out and began to work that over. As well as the striker knob portion which had some very fine lines in it. I now have that interface connecting quite squarely and the trigger feels crisp with a smoother primary pull than before. I also stoned the sear portion that engages with the bumps on the trigger as it had some very minor lines in it. This also helped smooth up the trigger with a distinct two stage trigger pull.

I'll re read your article Peter. As far as pennies? Anything ordered from here to any company would be a minimum of $10-$11 dollars just for the shipping. No matter how small the part. So as far as economics go it's cheaper for me to build it here.

I'm really not wanting to get into a scrap here. And it sounds like I am - so I'll take what I have and go forth. It'll shoot either way. Heck - maybe I've fixed it - and the sleeve I'll fabricate and then print your article out as re-assemble the rifle.

Villiers, good idea - but not likely for me to do it without some pretty detailed instructions. And hopefully I can repair it with what I've done so far.

Thank you all for the assistance -

Be well,
Steve

[Brian Dick]

I measured a few for you from my bin and the long ones all seem to be .510 in length + or -. There may be longer ones. Most of the ones I have were fitted to rifles so they vary in length.

[Alan de Enfield]

An excerpt from one of Peters old 'Jouster' posts in 2008 :

"......The COLLAR. You MUST have a collar and spring washer. This is what WE used to do. Put the front trigger guard screw into the trigger guard and body WITHOUT the washer or collar. Reverse it (that’s anti-clockwise …..) until you hear it click over the start thread and tighten it BUT COUNT THE TURNS UNTIL IT TIGHTENS AND LOCKS. Say, that it’s 7 ¼ turns to lock. Now do this with the collar fitted if it’s now, say 6 ½ turns, shorten the collar, a smidgin at a time, until the screw tightens up at exactly 7 ¼ turns. That way, you KNOW that the screw is tight, the fore-end is tight between the trigger guard and the screw and you are not crushing the living daylights out of the fore-end. And if it feels a little loose in a years time, then you can safely turn a few thou off the collar......"

[Norton1]

Alan, that's what I did - made a nice collar out of stainless. Just need to measure the pressure and then see about how well it's shooting at 100 yards -

Thank you for the measurement Brian - gave me a starting point -

Be well,
Steve

[Beerhunter]

All this talk about fixing the trigger has got me working on one of mine.

Every so often my No.4 Mk.1T would "single-stage" and so today I took a look at the trigger guard fixing. Sure enough with the front screw tight I got a single stage practically every time. Loosen it off and it goes back to the correct operation.

Now before I take it all to bits and do the counting the turns on the front trigger guard screw exercise, the symptoms look to me as though the bush is too short rather than too long. So finally to my question: if the bush is too long, it is OK to shim it out by the judicious use of washers?

I know that I should really fit a new bush and adjust it properly but, like our Marine friend, I'd like to save some time (procuring one) and money.

[Beerhunter]

if the bush is too long, it is OK to shim it out by the judicious use of washers?

Of course I meant "too short" but this system won't let me edit my original post.

[Norton1]

OK - I made a bushing and after working it down I ended up at .476 length on it. Nice tight fit and sets into the recess very nicely. I honed all of the surfaces, except the trigger bumps, to a nice finish and checked for alignment with Blue ****m. It's all nice and square.

I did everything I could to get it to go single stage and it is a lovely double stage trigger. 3 lbs of pressure on the first stage and 4lb 11 oz on stage two. And it is really crisp! I'd like stage two to be a bit lighter but will shoot it this way first and see what it does. Up pressure on the barrel is a tidy 4lbs and change. I happen to have a trigger gauge and used it to measure the weights.

So a question or two yet:

1) Is the up pressure only allowed on the last couple of inches of the wood?

2) How would I lighten the trigger pull a bit more? Most of my rifles have 3 1/2 lbs of trigger pull on them.

And I went slow - took me a while to get everything smooth and shiny and then parallel with each other.

Be well,

Steve

[Peter Laidler]

Your trigger pressures MUST fall into these categories. 1st pull between 3 to 4 lbs. 2nd pull, between 5 to 6.5 lbs. They are the specification laid down.

The last 2" or so of the fore-end has the barrel bearing surface so it's this area that the barrel bears down on.