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An older Belgian T-Bolt ... !

8K views 30 replies 9 participants last post by  Trailboss 
#1 ·
Although I have handled and shot the odd T-bolt or two over my 80 or so years of competition, I have never owned one. Then earlier this year, to satisfy a departure from my life-long love affair with CZ/BRNO, I started looking for/at older Belgian units.

Recently I acquired what is almost a mint example, age unknown, as it appears to be one of the so-called "parts rifles" ... S/N 64*** X. The stock is honey-coloured, probably one of the Sycamore units, finished in a semi-gloss, and if you look very hard, an odd pressure spot or two can be detected. The metal is very good, medium gloss bluing with the only flaws that I can see, being two tiny nicks on the outer rim of the muzzle.

It has been used, although I would say not heavily ... has the original box, test target and manual - even the original waxed wrapping paper and several 5-shot mags. Bolt action is very snug, with a little extra effort required to actually "lock it" at the end of the closing stroke. Trigger pull has some creep and measures right at 4# 2oz, except that for about one or two pulls in ten, it jumps to around 4# 12oz.

With the barreled action out of the stock, at first glance it appears that the trigger group is maybe bonded to the receiver, there being no visible attachment screws. On closer examination though, I'd guess that one has to remove the Magazine release lever and pivot pin to access a single attachment screw deep down in the solid machined trigger housing block. General appearance of the visible trigger and lever components suggest that a good de-burring and polishing would smooth the unit out. Certainly a lighter torsion spring for the trigger itself would be a major improvement. As for the bolt, quite a few traces of resin-like residue are present.

Which now brings up a few questions ... being less intrepid than I was 60-70 years go, l would like to have a few EXPERT comments/detailed instruction/diagrams on complete dismantling/assembly of both the bolt assembly and the trigger group before I start into "tuning it to my satisfaction" ... a search on the forum has not proven very satisfactory thus far.

As it stands right now, the rifle is very accurate, shooting <0.6"c-t-c groups, hand-held at 50 yards with CCI SV, but slightly larger of 0.8" using SK STD+

Mick - The Fuzzy Limey
 
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#3 ·
... as mentioned above, I already have the original Owners Manual, which does have a rather sketchy parts diagram of the whole action. What I need are detailed "gunsmith-style" techniques for sequential dismantling of both the bolt and the trigger group ... ie: in what specific order are the various trigger/lever components removed from the one-piece housing ... critical things to watch for, such as "flying springs", etc.

In an old rifle such as this, replacement components are next to impossible to replace, as a quick search of the various supply houses that cater to the FN/ Browning T-Bolt owner will testify.

As of now I have removed the magazine catch and spring, which was a quite controllable operation, which in turn allowed the removal of the trigger block from the receiver, via the single slotted retaining screw and washer. This has allowed me to clean up, de-flash, and polish both these components - and the magazine housing cutout area.

The question now is whether to remove the trigger pivot pin, and hence the trigger blade and torsion spring first ... or the upper lever/sear pivot pin and sear ... I'm leaning towards the former ... ?

Decisions ... decisions ... decisions ?

Fuzzy
 
#4 ·
... as mentioned above, I already have the original Owners Manual, which does have a rather sketchy parts diagram of the whole action. What I need are detailed "gunsmith-style" techniques for sequential dismantling of both the bolt and the trigger group ... ie: in what specific order are the various trigger/lever components removed from the one-piece housing ... critical things to watch for, such as "flying springs", etc.

In an old rifle such as this, replacement components are next to impossible to replace, as a quick search of the various supply houses that cater to the FN/ Browning T-Bolt owner will testify.

As of now I have removed the magazine catch and spring, which was a quite controllable operation, which in turn allowed the removal of the trigger block from the receiver, via the single slotted retaining screw and washer. This has allowed me to clean up, de-flash, and polish both these components - and the magazine housing cutout area.

The question now is whether to remove the trigger pivot pin, and hence the trigger blade and torsion spring first ... or the upper lever/sear pivot pin and sear ... I'm leaning towards the former ... ?

Decisions ... decisions ... decisions ?

Fuzzy
Old gun in great shape... Why you tryin to take it apart???
 
#6 · (Edited)
Continuing with these thoughts ...

A little experimenting with different gauges of music wire from my replenished stockpile ... finally settling on a 0.025" size ... produced the following trigger return springs ...





The upper pic shows the spring straight from my "winding jig" ... a #6 finishing nail set on a piece of 2x4, with a "flat-head" roofing nail as an anchor ... real precision stuff for the amateur ! Note; You must keep a lot of tension on the wire end you're pulling to keep the coils true and tight !

The lower pic shows the finished "bent to shape and trimmed" spring ... this is inserted in the main housing in such a fashion that pulling the trigger results in tightening the coil !

This particular new spring has, along with the stoning of contacting trigger, sear and firing pin surfaces, brought down the pull from the original 4-1/2# to a fairly crisp 2# 13.5 oz ~ 3# 0.5oz level. I say "fairly crisp' as the critical edge wear of almost 50 years usage has taken its toll of this old beauty. Maybe later, I'll head back to my vise and files and make a replacement sear plate ... !

Now go play with your own !

Fuzzy
 
#7 · (Edited)
Moving on a little further ... In checking over the barreled action before putting it back in the stock I noticed a slight trace of interference between the "long tail" on the trigger blade and the slot in the receiver which it engages to form a rudimentary trigger stop. FN/Browning had already pre-bevelled this tail on both sides as an assist ... more relief to the the two bevelled flats was required for better clearance ... This affects the smoothness of bolt cocking/uncocking as the cross-bolt is withdrawn from the receiver.

After action installation in the stock I noted that the plastic trigger guard is slightly warped and binds slightly on magazine clips ... scraped it lightly for more relief but will tackle this problem later. Initial hold-down screw torque was set at 20 in.oz.

Shot five 10-shot groups at 25 yards on a NRA 50 yard Light Rifle target with no bore cleaning or pre-fouling shots between groups. Shots were in simulated Prone position from my modified Wheelchair/rollator, same as I'd do in a regular CMP match.

Group 1 - Federal Auto Match
Group 2 - CCI MIniMag Soilds
Group 3 - CCI SV
Group 4 - Norma Tac-22
Group 5 - SK Std+











All pretty good with CCI SV hanging on to its' well deserved reputation as a "good buy" !

Fuzzy

PS: Checked the triigger pull at end of tests ... ranged from 2$ 15.2oz ~ 3# 0.7oz on my Lyman gauge ... safely lifted my CMP "standard" 3# weight OK.
 
#10 ·
... That trigger will be just right for the match in August ...
The trigger may be alright, Don ... BUT ... not so sure about the character pulling it - lol ! If nothing goes wrong on Thursday and the surgeons' prognosis is correct I hope to be back "on the firing line" by then with all "four cylinders" functioning at the correct pace !

As for the rifle I'm hoping to unravel the mystery of how the bolt comes apart and what improvements in smoothness I can affect between now and Wednesday - lol ! It's moving very slickly without a round in place but a bit sticky pushing one into the chamber ... would be unsettling in Rapid Fire stages.

Fuzzy
 
#9 ·
I wish I had more info, but I've never taken mine down that far.:eek:

Fuzzy, it sounds like you are going to end up being one of our resident experts on the Belgium T-Bolt.:bthumb:

I like the later Belgium, (parts cleanup) T-Bolts the best because I don't have to worry about a salt wood stock.
 
#11 ·
Since the last post I have had the bolt apart ... fairly straightforward - push out the "headed" pin that retains the T-lever, with slight restraint against the firing pin spring.

Cleaned all components thoroughly and lightly stoned all contacting faces and sharp edges. Discovered a fair amount of sludge residue and even some cleaning patch threads trapped in the main cavity bolt action feels much crisper and a slight reduction in the trigger pull variations ... now right on 3# +/- 1oz.

I have now re-installed the original Williams mid-barrel open rear sight and adjusted it for a nominal 50 yards zero, centre-hold, with typical standard velocity ammo. This sight leaves a lot to be desired in its' adjustment capabilities ... a single screw locks the sight blade in position for both windage and elevation ... a real juggling act to get right !

I may consider a receiver-mounted aperture rear sight ... tried an FP-GR-TK from my stockpile, but would require cutting away a clearance "slot" in the forearm wood. Similarly, replacement of the front sight with a Lyman globe might also help ... did not try this yet as removal of the blade cover would probably result in its' destruction, and not sure what size dovetail lies underneath.

Fuzzy
 
#18 ·
. . . I have noted in all of the live firing tests performed thus far with the "new" Belgian T-Bolt, that although I've got the bolt and the toggle lever working as smooth as silk in opening and closing operations, it becomes quite "rough" when loading actual cartridges into the breech.

On some "loads" the round only partially enters the breech and then forward bolt motion comes to a screeching halt. It is doing this regardless of what brand or variant of ammo is in use. I can find no roughness on the magazine lips either ... I have three 5-rounders currently.

Any other Belgian owners experience this problem ... any known cures ... was wondering if perhaps this is a magazine version problem as I've noted that there are after-market units available these days online. Possibly the mag lips are gripping the round too tightly ... ?

Fuzzy
 
#20 ·
. . . I have noted in all of the live firing tests performed thus far with the "new" Belgian T-Bolt, that although I've got the bolt and the toggle lever working as smooth as silk in opening and closing operations, it becomes quite "rough" when loading actual cartridges into the breech.

On some "loads" the round only partially enters the breech and then forward bolt motion comes to a screeching halt. It is doing this regardless of what brand or variant of ammo is in use. I can find no roughness on the magazine lips either ... I have three 5-rounders currently.

Any other Belgian owners experience this problem ... any known cures ... was wondering if perhaps this is a magazine version problem as I've noted that there are after-market units available these days online. Possibly the mag lips are gripping the round too tightly ... ?

Fuzzy
Fuzzy, my T-Bolt is a 1966 Belgium made. I checked the function and it's quite smooth. The top magazine round is pushed forward about 1/8 of an inch when closing the bolt, the round then pops up and into the double claw extractor where it's firmly held inline with the bore. It slides smoothly into the chamber.
 
#22 ·
... thinking again on the subject of the rear aperture sight used on the early T-bolts ...

After checking all over the internet for available examples ... an odd one or two on E-Bay and similar sites at greatly inflated prices - found one at an antique dealer who valued it at almost $200 ... he must have been puffing hard on his hookah !

Veering away from the "narrow path of purism", I note that Williams still offers their good ol' WGRS-54 dovetail-mounted rear aperture sight, but show no geometric data in their catalogues. Have any of the old Belgian T-Bolt owners here tried this unit as an acceptable substitute ? I'm ordering one to check out.

Fuzzy
 
#26 ·
... in response to the above two replies ... I wrote in an earlier post that the bolt and action had been totally dismantled, cleaned and honed/polished where required and that the overall operation of the bolt "without ammo" was very slick. The problem seems to lie in the manner in which the top round is removed from the mag and inserted into the breech. Firstly there is a definite resistance to actual removal during the forward stroke of the bolt ... secondly, on some occasions the bullet tip does not always align with the breech. One thing I did ascertain before having to take an enforced break, was that full bolt retraction is a "must" for each loading stroke.

Right now, while recovering from cardiac surgery, any corrective work is at a standstill, but I'm going to evaluate lip contours/smoothness, and feed angles on each magazine once fit again.

Interesting little puzzle !

Fuzzy
 
#27 ·
Fuzzy, if some of the bullet tips are not lining up perfectly with the bore it suggests that the cartridges are not being released from the magazine soon enough. On mine, after 1/8" push forward the rounds pop up into the grip of the double extractors and are always perfectly aligned to the bore. If your mag is not releasing its grip and is not snapping the round up and into the bolt face/extractors grip, then I suspect that your magazine has been crushed or dropped on the lips. Try a different mag.
 
#29 ·
Having now fired a hundred or two rounds using all three old mags that came with rifle, I have pinned down the problem to just one of the three, now with numbered ID's. Visually, even under a magnifying glass, I could detect no difference between them. Finally, after stripping each down I identified the problem ... the internal spring in that mag was installed in the wrong orientation ... the two "terminal coil ends" should face the convex rear face of the mag !

Problem solved !

Fuzzy
 
#28 ·
Harking back to my earlier suggestion of the Williams WGRS-54 sight as a suitable replacement for the original Browning aperture unit ... the one I ordered arrived by todays' mail.

As received it would not fit the Browning receiver dovetail ... this had been referenced as a possibility in the Williams literature, along with the very simple solution ... light sanding of the lower surface to effectively "widen" the sight dovetail. This took about 7-8 minutes of careful rubbing of that surface on my "flat plate" using 220 grit paper as the medium.

With the sight installed at the very rear of the receiver dovetail, and the elevation slide in the lowest position, a 25 yard centre-hold zero is quite feasible using most standard velocity ammo ... Norma Tac-22, CCI SV, SK STD+, etc.

The installation is very neat and far less bulky looking than the original Browning unit. It has a 3-screw set-up ... one to lock the sight to the dovetail ... and 2 separate screws for elevation and windage locking ... a big advantage over the original mid-barrel sight adjustment concept that uses a single screw for both adjustments.

Fuzzy
 
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