Mk1 vs. Mk2 Buttstock Return Springs

[hatrick]

Is the Mk1 return spring the same as the outer Mk2 return spring and the only difference is they added a smaller second inner spring on the Mk2?

I was assembling my Mk1 buttstock and a dual Mk2 spring set fits no problem and it seems a bit stiffer than the single Mk1 spring (which seems like a good thing). Any issues using a Mk2 spring set in a Mk1 buttstock?

Thanks

Information

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[Ammoman]

It says in the manual "Two spring constitute the Mark 2; Mark 1 is shorter, using one spring."
VOCAB # BE 1813 for the Mk 1 and VOCAB #'s BE 6896 and BE 6897 for the MK 2

So I'm guessing the MK 1 butt may be a bit shorter so using a double spring might be a bit too strong to use as a direct replacement.

[Lee Enfield]

Here is the 1955 Canadian EME springs use in the Bren.

I suspect that the MkI spring had more than 6 coils (probably a typo?).

[hatrick]

This is for my Historic Arms semi auto Bren. Right now it has a single Mk2 outer spring and I was thinking of going to the double spring for a bit more recoil protection.

[Peter Laidler]

The double return spring was to counter the extra impetus to the breech block and piston assembly. This was caused by the increase in diameter of the gas hole in the barrel (Mk1 to Mk1* barrel). As a result the working parts hit the buffer plate with such force that it cracked the buffer plate where it joins the rounded part at the rear.

Opening up the gas port also caused a more violent unlocking of the breech block by the piston post. This resulted in the piston post spring breaking and thus, the piston post spring plunger bottoming out and rounding the bottom end........... A real dogs dinner! So the piston post plunger was replaced with a shorter one.

And the buffer plate STILL cracked in the circular area on the face. BUT, to make life easier for the gun crews, a spare piston post spring was always kept in the spare parts tin, in the wallet or holdall

As a bit part amateur regarding Brens, I say that the OUTER spring remained the same.

[browningautorifle]

As a bit part amateur regarding Brens

I was hoping you'd see this post.

[Peter Laidler]

The classic Bren total fiasco was machining gas escape in the gas cylinder, DIRECTLY underneath the bipod sleeve. Have a look at a Mk1 gas cylinder. Have you ever heard of such folly? The instructions said that after every couple of magazines, the gun crew should twist the gun on the bipod - left to right to left - a few times to break the carbon away. Good idea - if, during the heat of battle in France in May and June 1940, they remembered to do so. One or two (?) didn't...... The result was a bipod stuck solid on the gas cylinder. Even WORSE was the crews that DID remember to twist the gun on the bipod. The diamond hard carbon fouling was harder than the poor stainless (?) steel gas cylinder. So within a short time the gas cylinder and bipod sleeve were ground down, the gas escaped and soon was insufficient to cock the gun.

The quick fix was to increase the gas by reaming out the gas prts in the barrel.

Even BETTER was that for the first 5 years of production and service, until 1943 or so, Locking shoulders were not supplied as spare parts. So a worn out gun with oversize CHS remained a worn out gun with excess CHS..

As for the pure horse manure that the gun was so accurate that it could be used as a sniper rifle...................

But all that said, I loved it to bits. No doubt, the best incarnation was the Mk3 that had all the troubles ironed out and into the L4 A4. Just providing that you told the young Armourers in no uncertain terms, that you must never, ever, not NEVER rush a job working on a Bren.

[csmarcher]

The classic Bren total fiasco was machining gas escape in the gas cylinder, DIRECTLY underneath the bipod sleeve. Have a look at a Mk1 gas cylinder. Have you ever heard of such folly? The instructions said that after every couple of magazines, the gun crew should twist the gun on the bipod - left to right to left - a few times to break the carbon away. Good idea - if, during the heat of battle in France in May and June 1940, they remembered to do so. One or two (?) didn't...... The result was a bipod stuck solid on the gas cylinder. Even WORSE was the crews that DID remember to twist the gun on the bipod. The diamond hard carbon fouling was harder than the poor stainless (?) steel gas cylinder. So within a short time the gas cylinder and bipod sleeve were ground down, the gas escaped and soon was insufficient to cock the gun.

The quick fix was to increase the gas by reaming out the gas prts in the barrel.

Even BETTER was that for the first 5 years of production and service, until 1943 or so, Locking shoulders were not supplied as spare parts. So a worn out gun with oversize CHS remained a worn out gun with excess CHS..

As for the pure horse manure that the gun was so accurate that it could be used as a sniper rifle...................

But all that said, I loved it to bits. No doubt, the best incarnation was the Mk3 that had all the troubles ironed out and into the L4 A4. Just providing that you told the young Armourers in no uncertain terms, that you must never, ever, not NEVER rush a job working on a Bren.

Love your posts and replies, there is always an interesting story, anecdote or tip for us Bren collectors and shooters !!!

[Peter Laidler]

Thanks for your comments Company Sgt Major Archer. The initial problems with the Bren lay at the door of the committees and dare I say it, the trials and testing teams from the old small arms school at Hythe. Everyone, from the War Office downwards wanted the gun to be all things to all men. They wanted a jack of all trades.............. But when it came to push and shove and when the going got tough, that's when the Bren really excelled and the tough got going. As tough as old boots........ The only job it really excelled at was the Infantry section light machine gun. It was never any good as a sustained fire machine gun or in the AA fire role or overhead fire support role or to replicate the 2" mortar fire. Taught to EVERY recruit in his basic training. This ensured that every soldier was capable of using the section machine gun. Unlike the Vickers teams who were specialised

Did I love it to bits? Yes. Do I still remember all of the gauge sizes ? Yes. Repair procedures and methods....... Yep!

[csmarcher]

Peter

Timing is a funny thing....a friend of mine here in the US has just had a Bren Mk II rebuilt/restored into a functioning semi auto, and brought it over to me as he had a few questions.

To my horror and astonishment the builder who restored it built it with an early Mk I gas cylinder with all the additional holes under the bipod. I told him in no uncertain terms to get the gun back to the builder and replace that with a Mk II cylinder which I had in my spare parts box or he would have nothing but nightmares getting the gun to run reliably !!!

My thoughts went immediately back to your advice here on the forum !!!

So, once again, thanks Peter for all your great Bren advice !!

Regards from California

Gary Archer