Longbranch 1941 No4mk1T replica (Trepilca)
Updated: Jul 6, 2022
Of the 3 factories to convert No4 rifles to the "T" for telescope specification, the Longbranch versions are the rarest and hardest to find. Official numbers from the factory give wartime production of an initial 200 sequential serial numbers with a possible 860 made as an all-time total. The rifle was not the rarest part though, the No32 scope production (designated CNo32) was delayed and experiencing difficulties, so some rifles were made with the contemporary Lyman Alaska sights and custom brackets. When the CNo32 scopes did start flowing a phenomena occurred where some serial numbers were issued more than once - when caught these duplicates received an extra sequential serial digit. I have come across one real rifle, several replicas (fakes in the wrong hands) and several of the real scopes of all versions - quite often with matching brackets, carrier tins and other accessories. I may add photos of these real items to this thread if a dedicated thread does not take sprout,
There are several reasons to make a replica - most prominent of all is a recognition that I will never own a real Longbranch Rifle or scope and if I could maybe they would be unaffordable - let's not go into my proclivity for "luck" except for the following circumstance: A barreled action was being passed between Canadian re-enactors for $50 and then was offered to me...upon inspection it was a very worn, beaten and stripped Longbranch 1941 No4Mk1.
So my first step was to build it into a complete but affordable rifle with an extensive used and some NOS Longbranch parts kit that I could muster - the wood selected was the worst of the used Beech examples. It did not take long to build up and perform safety and function checks. The Enfield world has a phenomena where you simply cannot buy precision... when shot for effect at the range this beater / "bitsa" rifle grouped tighter than any I had previously experienced with Mk7 ball ammo. Intrigued, I wanted to see exactly how far this $50 rifle could go...would it take a scope (replica No32)? Can I practice the scoping techniques on it? Can this be my new "carry" rifle for reenactments and for hunting?
So I set about the scoping task with a laser bore sight(er) and a couple of sets of brackets and pads to choose from and a decent desktop pillar drill. H&H took great precautions to put the front pad as close to the receiver ring as possible and high enough that the rear pad would be in the narrow meat of the rear locking lug on the body. After a while they also skimmed this front pad area on a mill to achieve a standard datum for their in-house made pads (which had all features generated on the rifle, not like our current "completed" commercial pads) to track in a similar bore alignment each time. Others have written about the H&H process past this detailed start point and still more have written about taking the commercial pad and bracket kits to make a replica. So here I will emphasize my process and other build / measurement points.
I filed and linished the front pad area of the receiver and the pad base and lug to be flat and square. Using super glue the pads can be held on the receiver body and the scope bracket gently bolted up (with scope zeroed) - thus the laser can give us a rough POA / POI trend. I like to only take material OFF my work - so the laser was kept left of the POA.
A "machinist" method of making a single piece assembly is to mark, then box (use lines to intersect the extent of holes) then center-dot so that the locations can be developed with simple tools and then corrected as necessary.
When I had the center dots in the right place for the pad it was glued back on again, laser sighted and then knocked off for machining the holes - after each hole was run through with the core drill - the tap was loaded into the chuck for a "machine start" - this keeps the tap vertical above the hole that the drill was just taken out of. I hand tapped the threads from this start (about two turns in) - the body was very tough for this small tap - lots of thick tapping lube required and I found each thread turn would have to be split into 1/16 of turn advances - then completely unwound to clear the chip and then then advance 1/16 turn again - painstaking!
With the front pad in place, the rifle could be shot for actual POA (gingerly) - this confirmed that the front pad was just to the left of where it needed to be - giving any adjustment as material off the pad or bracket - in this case the amount was so small a click was given on the scope to make good.
With this confirmed success, the rear pad can be positioned - this controls the base elevation of the scope on the rifle - where the scope axis crosses the barrel axis. As mentioned earlier having the screws in the rear lug "meat" is the invisible challenge. The first hurdle you will notice though is the gap between the receiver wall and the rear pad - I gauged this (feeler gauges) and found I had to make a 24 gauge steel shim (now I have a shim design to make by hand for others and will get them commercially cut soon). I also use extra long screws for the machining and mounting process - these are disposed of after machining and can be cut back to get a reference measurement to have the final screws finish smoothly (invisibly) in the inner receiver wall as per H&H.
The rear pad also requires the 1/4 BSF tap to go through the wall and rear lug. The photos above (bottom) show how this works out. I used a very high elevation setting for the scope as I was assuming that the 100 yard point would be at near the bottom of the scope adjustments and my shooting sweet spot would be 30 MOA higher (400 to 500 yards) which then would put the graticule in the "optical center" of the scope tube for best vision at longer range shoots. With this high elevation I still made the rear lug meat (but you can see I was at the limit of this built in range) - I have the choice to put a 0.030" scope shim in the bottom of the rear cap cradle to relieve this as needed - which works exceptionally well. The photo top left shows the initial Sarco No32 Mk1 scope that was used - the bracket was reworked and repainted to be more authentic. Top right shows the Numrich No32 Mk2 scope that was trialed on this rifle - it stayed on through the 2020 CMP season. Of interest as it was being prepped for paint the receiver showed traces of original "jungle tropical green" protective paint from its previous service.
I did fasten the pads and pad screws with solder - very little is needed - so pay more attention to the heat torch - the receiver is a huge heat sink and will take more direct heat to reach the right temp to accept solder than the pads. I did this rifle on my kitchen wood stove - its already made for heat! The stove stayed "warm" for paint - I used it to cook the high temp paint.
Ill think through and drop any other pertinent points and tips back into the sequence that best suits them as they come to mind
I have started supporting a re-enacting with the 1st HQ Canadian Paratrooper group so having a Longbranch rifle in a reproduction Canadian chest fits right in.
In 2020 the LB Treplica went onto a CMP shoot with the Numrich No32 Mk2 scope - the scope being the limiting factor for adjustment - yielding clicks just over or just under those required. Together we showed rapid fired and slow fire from 3 positions without fault or drama - scoring 430-5X out of a possible 500. The rifle can still go to do more..
For 2021 I trialed 3 of the Red Star Mountain No32mk3 scopes. These are is modelled on the original internals and are operationally the same as the real thing. In practice these fell out of focus in the first few shots - while they offer a lifetime warranty - they have only sent a rebuild instruction for me to correct the focus and build.
This leaves me going full circle to see what this rifle can do with a decent scope - I have a Bausch and Lomb Elite 2000 2-7 x40mm scope which is in great condition - it is clear and precise and always returns to its optical center marks on the 0.5MOA clicks.
I tested this rifle and scope combination the other day and the results were amazing. A cloverleaf, group of 3 rounds at 25 yards, a 2.5 MOA group of 6 at 50 yards - in the exact position that the laser indicated the scope bracket was set by machining and assembly. The 100 yard group produced a virtual score of 47 points 1X after adjustments of 2MOA left and for elevation (the 0.030" shims doing their job).
So far this rifle has performed well in local CMP clinics - with a couple of tweaks and upgrades each year for an annual outing (I have to rotate a couple of rifles).