SUIT detaching'shearing from mount!

[mrclark303]

Hi all,

One for Peter and Mike here......Out shooting with L1 friends the other day and both had failed SUIT mounts, Charlie .303 and Paul had exactly the same issue, (Charlies in the past, now fixed) and Paul's whilst shooting on Wednesday......Suit and mount detaching from the (genuine) top cover with the two rivets shearing off at surface level.

So Peter and Mike, any low flying SUIT's back in the day chaps, if so what was the official/unofficial fix?

Information

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[tankhunter]

John, your getting MORE recoil with your SLR's, as they are hand cocking only. The original semi spec rifles were more 'cussioned' because some of the gas was directed to drive the working parts system.
It would be a simple fix to fit new rivets to the 'T' mount on your top covers. I cannot remember without checking my own specimen. if the 'T' mount is steel or alloy. I THINK it was steel. In which case, a LIGHT run of MIG Weld down either side on the 'T' mount. Along the top cover mount webs, would secure it admirably! Job Done!

[mrclark303]

Cheers mate,

Thanks for the feedback buddy, forgot all about your package , it will be on its way this week.

Cheers, John.

[Peter Laidler]

I wouldn't necessarily agree with Tankie about the L1A1 semi being more cushioned because the amount of gas diverted to operate the working parts was minimal/marginal. And don't forget, 'recoil' has/is already taking place at the start of detonation and increasing as the bullet is on its way up the barrel - even prior to getting past the gas port....., but I digress! I seem to remember writing about this and the myth that the bigger the gas port the more the recoil - but I digress a bit more.........

Going from memory, the SUIT cover is made from 3 parts. The actual cover, the open-square section reinforcing bit and the T shaped mount bit. What we don't know is whether it's the steel square section that's separating from the cover or whether it's the T shaped mount part that is breaking free from the square section.

I'm not sure that I would ever tig anything to the actual thin steel cover bit as any forces would eventually just tear away at the cover.

My first idea would be based on my view of the SUIT sight which is based on the mnenoic SUIT....., Shooter Usually In Trouble. And that is to give the sight and cover to someone you don't like as a fishing weight. It was always crap and only came into its own when it was revamped as the SUSAT

I seem to recall reading on this forum that some of these have been repaired using aluminium rivets and it's these alloy rivets that fail under rotational moments.

[mrclark303]

rotational moments, Peter...... you can get tablets for that

Its the T Piece mount assembly separating from the spot welded mounted base......the rivets literally shear away flush with mounted base. I have asked our friends across the pond to invert their gas plugs to compare and contrast recoil, an interesting exercise chaps.

[Peter Laidler]

The recoil thing is a project that was regularly a student experiment feature and well documented. Won't go into it again but some of the notes were repeated on an earlier thread several years ago. To register how little effect the operating gasses venting via the gas port make you can just rotate the gas plug to shut them off and it barely registers

The T-piece is rivetted through the cover and the reinforced open square section as I seem to remember it. Just re-rivet I say, with red-hot steel rivets. When they cool and contract..... there ain't a lot of recoil going to pull them apart!

We used to have a few No78(?) telescopic sight for the ill fated L1A1 'marksman' rifle and they were mounted on that tinny top cover and open square reinforced part too and suffered the same fate

[tankhunter]

Cheers mate,

Thanks for the feedback buddy, forgot all about your package , it will be on its way this week.

Cheers, John.

Thanks John, I know where Peter is coming from on his take on this. He is far more qualified than I, with his white Professors coat & qualifications! LOL! Seriously though, it MUST be a factor going towards the extra stresses imposed on SUITS if you are using a hand cocker. The gas that is bled off to drive the working parts is a fairly high pressure too. & that diverted against heavy working parts, recoil springs Etc. simply MUST add to what I call the Cushioning effect, surely? Even a bit!!

Indeed, Peter & myself, & other Service Armourers have encountered the 'T' sections coming loose, or shearing off during Service usage. This has been covered before in threads on this forum. The standard repair, was to re-rivet, as Peter has stated. (Brit repair was a cold rivet) I have also seen weld deposit runs down the side of the 'T' piece to the support webs on the top cover.
Mig & Tig are SUPPOSED to be Non Buckling methods hot welding. Not having done any myself to top covers, I cannot comment on the topic of Buckling. If you look at the support webs on SUIT top covers. Some APPEAR to be spot welded. Some appear to be brazed.......My own opinion is that Brit spec top covers are SLIGHTLY thicker than FAL T/C's if you play with them. I have found that FAL's tend to get buckled /damaged far easier than Brit Spec versions. I personally, would re-rivet with good quality steel one's......It's make your mind up time!