No4 Mk1 T Rebuild

[Peter Laidler]

Good on you TBone. You can understand now why I scratch my head when I see fore-ends for sale, purchased and slapped straight on. We spent months and ruined many, many (and patched even more to correct and get them fitted - eventually.....) fore-ends getting them right and I NEVER found one that would go straight on, properly that is, without fitting! Obviously all of the perfectly fitting ones went out onto the commercial market and the difficult buggers stayed in the Ordnance Depots waiting for unsuspecting Armourers to fit them.

You can also see that fitting a fore-end is a visual and experience thing and not really something that can be explained away.

[Claven2]

Ah yes... I see you have the Seig X2 mill. I used to have one, not a bad little starter mill. You may wish to invest in a proper vise though - it makes ALL the difference. Project is coming along nicely - keep it up!

[tbonesmith]

Tonight I made off my newly patched draws, and carefully fitted them to the sear lugs, and once again went just a fraction too far.
It wasn't grossly wrong, the barrel had the correct amount of upward pressure from the forend, but the barrel didn't have that really snappy return to centre line. And I had no more room to adjust the draws to suit without allowing the whole bedding arrangement to soften.
I put a couple of layers of paper tape on the back of the forend where it butts into the wrist to take up some tension, and that gave me the req'd "snappiness". I thought about gluing a shim of timber here as I've done on others I was setting up, but I'm not compromising anything at all on this one.
While setup I checked for bearing at the reinforce, and had none, so I decided to once again patch the draws and the reinforce as well.
I was able to remove the old patched draws without enlarging the area at all, so no harm done.
I don't care if I need to do this 20 times, I will be getting this right, though I'd prefer it if I'd just get it right tomorrow.
I know this is pretty picture heavy for no real progress, but I thought it would be just as productive to see where I got it wrong, as where I got it right.

[Peter Laidler]

Just make sure that you haven't got a warped fore-end TBone. Difficult to identify because the run-out takes place over a couple of feet

[tbonesmith]

Well today, I went for it again.
I bulked out my reinforce patch, then fitted the draws a bit, then took down the reinforce patch to close to original size, then fitted the draws.
At this point the draws are about right, the rear of the is action held off the wood by the fit of the draws by 1-1.5mm, and the reinforce is holding the barrel up, so the end of the barrel will not contact the forend tip.
As I fit the reinforce to the knox, the barrel tip moves closer to the forend tip, and as it does I'm able to slightly adjust the draws so that the barrel is in the centre, and tightly held there, the rear of the action is still off the wood.
The reinforce is closely fitted to the knox, and the front of the receiver starting to bear on the wood, but the barrel tip has yet to contact the forend tip(by less than 1mm).
I scrape the bearing surfaces of the reinforce and the timber under the front of the receiver by SFA and still don't get there
I lay the forend on my piece of breeching up glass, and it is warped in the vertical plane by 2+mm over its length.
What is my best option from here? Repatch the draws and ensure a higher fit at the rear and refit the reinforce as required? I don't want to pack at the muzzle as when I fit the top front guard it only just fits, and any elevation of the barrel will mean I need to modify/grind the steel which I'm not doing.
This fit up felt so good, in how it was going. Bearing was good, and progressed in a predictable manner, and I really felt a "feel" for it. This set back is disappointing, but I'm learning buckets.
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[rgg_7]

I see you have contact under the ""King" screw ( I know the Brit's call it something else) however no contact marks at the rear behind the draws. Blacken the underside of the receiver and put it back in the stock to check for rear contact. Draws should show full contact on the face...I only see partial. Also the knox has to be 100% contact...looks to be high spots.

Worst case it to remove the draws, check for fit and forend pressure and then install your draws. I've done it this way many times and it eliminates the variables in fitting the draws, bearing surface and forend pressure at the same time. Wood is not very forgiving.

Hope this helps,

Ron

[Peter Laidler]

RGG, there needn't be a fore-end bearing behind the draws........... should there? That's in order to allow......., anyway it's getting into the VERY technical there........ Just check that before you leap TBone!

[tbonesmith]

If there is contact at the rear of the receiver, there is no possibility of there being any upward pressure from the tip of the forend. As when the reinforce is gone completely, and the front of the receiver bears on the wood there is no contact at the forend tip.
Yes the draws should bear completely.
I've seen no other information stating the requirement for contact at the rear.
I've had another look at the timber and barrelled receiver and can say with confidence that all that needs to happen is that the draws need to be fitted again (patched and fitted), and fitted so as to when tight, hold the back of the receiver off the timber, enough to affect appropriate pressure at the forend tip.
As for the highspots on the reinforce, mabe but it's pretty close.
By packing the rear of the receiver with a small packer, I get the correct pressures, and bearing at the reinforce, with none at the "kingscrew", meaning I can appropriately patch and fit the draws, relieve the reinforce until the "kingscrew area and knox are both bearing, and I should be home and hosed.
I don't think the tiny bit of bow to the forend will mean any thing to the fit up. But in frustration yesterday I think I looked for factors other than yours truly, there are none.
While it's coming along, and I know I'll get there, this really is a very difficult little operation. Every component of the operation effects every other aspect of the fit, in ways I couldn't predict. So without this knowledge of how the whole job inter relates it's no surprise I work myself into (baffling) corners. I said at the start of this part that I'd fitted some others up, well all I can say is that while they've shot well, they could not have been properly right, or I might have just got lucky, most critically I wasn't using engineers blue so how could I know, really.
I'll get you next time, and I'm glad I don't need to patch the reinforce again.
BTW Peter, can any adjustment be made to the front of the bedding area( under the front trigger guard screw), or is this a NO NO, as I mentioned I scraped it in hope but just enough to remove the blue ie.SFA

[tbonesmith]

Well after once again patching the draws, I very carefully fitted them to the recoil lugs, being very careful to have the right angle and then maintain it. Then I adjusted the reinforce, and very, very lightly the area around the front trigger guard screw. All the while checking the centering of the barrel, and its pressure on the forend tip.
The barrel and receiver are now bearing as they should( to the best of my knowledge and ability) and the barrel and forend feel just like a well set up factory rifle.
I will fit the butt and get the rifle together for some iron sighting testing/shooting very soon.

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[tbonesmith]

Well tonight I fitted the butt. I have yet to properly fit the butt plate but I put it on for the moment anyway. The butt is a good tight fit, and as I've read to do, I left the shoulder of the butt to the taper, 2mm proud of the reciever, butt socket collar, the bottom of the butt taper didn't bottom on the bottom of the socket, but it's very firm. Also when I cranked on the bolt through the butt with a shifter on a square shanked driver this pulled up to a less correct, but more sightly 1mm gap.
I also found out why you sometimes see the top of the butt (at the socket) linished flat, because with the wood a bit big and proud, it fouls the cocking piece, and you can't close the bolt!
If anyone has any pictures of these done in service, would you please help me out and post them or direct me to them, as I don't have one with this mod.
So because of that, no shooting this beast tomorrow, as soon as someone posts a suitable pic for reference I'll sort it out, then have a shot.
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