Dimensional differences and bipod types?

I have 2 semi-auto convertion Brens, and am referring to S.A.I.S. #5 for my info:
- a MkI by Wise Lite with only 1 dovetail, Enfield '43 body, Mk3 gas cylinder
- a MkII by Historic Arms, only marked Bren MkII on right side, odd gas cylinder

The gas cylinder on the MkII is like the SAIS Pg 28 Mk.2 (with the big ears), but has oval vents under the bipod sleeve like a Mk.I gas cylinder, although the rear vents are circular as shown for the Mk.2. Is a Mk.2 gas cylinder with bipod sleeve vents odd?

I also have a quandry over the bipods. I have:
- a Mk.I
- a Mk.3 (or is it a Mk.2? The SAIS Pg 24 isn't clear on the differences. All I can see is maybe that the Mk.2 has the split pin on the inside, and the Mk.3 has the split pin on the outside. Mine has the outside pin. It says the shoes are different, but it isn't clear how they are different)
- what I assume to be an Aus/Can Mk.3 as in the page insert
- what I assume to be another Aus/Can Mk.3 but with flat shoes identical to the Mk.I shoes, basically a Mk.1 with non-adjustable legs.

Now here's the thing. I can fit all the bipods on the MkII Bren, but only the Mk.3 (or is it Mk.2) on the MkI Bren.

The other three bipods will just not fit onto the MkI Bren, even with a little "persuasion". They all stop about 1/4 inch short of the lugs engaging.

Has anyone any ideas? I thought the bipods were interchangeable. I can't discern any dimensional differences.

I'd also appreciate any input on the Mk2 gas cylinder with two rows of holes, and clarification of the bipod types, especially the apparent Mk.3 with flat shoes (no spike, and a hole).

Ideas/comments/suggestions/clarification/etc. greatly appreciated.

Cheers

The Mk2 sounds like a Inglis Bren

bren markII

The inglis Marking may me there but under a patch which holds the rewelded reciever together.

From memory
Theres a Mk1 bipod (The one you know of) with adjustable legs
A British mk 2 which has a head of malleable cast steal.
A British mk 3 which was like a Mk2 but lighter.
A mk 3 Canadian which is the same as the mk1 apart from it dosnt have the adjustable legs
A mk3 Aussie which was like the mk3 Canadian but had the feet of the mk2

With the fitting of the bipods, it could be that the Mk2 gun has a badly worn cylinder (Common problem with this type) so all 3 fit. The Mk1 probably has the improved gas cylinder with only one row of holes and will be less worn. Check all the bores on the bipod heads for carbon deposits or burrs, same goes for the cylinders, but dont use emory cloth on the cylinder.

ATB, Chris.

Gas cylinder types -

https://www.milsurps.com/images/impo...scyltext-1.jpg

ATB Kevin

I went looking for that pic in one of your previous posts but couldn't find it. A very clear presentation.

Great information guys, thanks very much.

Brit Plumber, thanks for the pointer to that very useful thread. I think you are dead on. The "Bren Mk.II" font is exactly the same as the one pictured in that thread, and the weld will have gone right through the Inglis marking. An Inglis it is, then.

Sounds like I have both Canadian Mk.3 (Mk.1 feet), and an Australian Mk.3 (Mk.2 feet), as well as a Mk.1 bipod. Still not sure whether the other is a Mk.2 or Mk.3 though. What are the "lighter" signs?

Agreed, the Mk.I Bren with the Mk.3 gas cylinder may be less worn, but I'm sure that everything is clean, free from burrs and carbon. However, I will double check and clean all of them, maybe add a little lube, and try again. I take it that they should all interchange, then?

Kev G - great picture. Worth more than a thousand words. I have the Mk.2 Early Canadian. Goes well with it being an Inglis, I guess.

Thanks for all the input. Really appreciate it.

Cheers.

In short, all of the bipod sleeves should fit all of the gas cylinders - they're interchangeable.

As for the identification by mark/type, it's fairly easy as you've been told but the difficulty arises when parts are, say, interchangeable parts from, say, an Australian bipod are fitted to a UK bipod. That can cause a bit of head scratching. But if you do get confused and start to worry, I suggest that you load up 6 magazines, book the range and go out with another Bren fan on Monday lunchtime and let the first magazine go down in single shots, the next magazine in short bursts, as per the book, then the next 4 let them go hammer and tongs. You'll find that bipods dont have the same fret factor afterwards!

Quote:

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Originally Posted by Peter Laidler

let the first magazine go down in single shots, the next magazine in short bursts, as per the book, then the next 4 let them go hammer and tongs.

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I wish I could, but they are both semi-only. This great democracy trusts me with various rifles, pistols and revolvers; but not in full-auto. I don't have the money or connections (i.e. ability to bribe) to be allowed such. Still, a lot better collection of working toys than I could ever have had back in Blighty as a civvy. God bless the Second Amendment.

Cheers.

[QUOTE=Peter Laidler;145289]In short, all of the bipod sleeves should fit all of the gas cylinders - they're interchangeable.
I have just helped a contact out with the exact same problem raised here on Bipod head fitment.
I advised a good cleanout of the head after soaking in a carbon removing/softening solution. Check the lugs on the gas Cyl & LIGHTLY dress the lugs if burred.
Result: The bipod he wanted to fit to his gun went perfectly!
He had previously tried three different bipod assemblies to his gun & only one fitted it at that time.
it was NOT the variant he actually wanted to stay on it. After effecting the above discribed action, it now fits & he is one Happy Bunny!
It was legendary in Service to use Coca Cola (& Still is!) on carbon to soften it before removal. Works a treat on vehicle cylinder heads for decoking too!........LOL!

A bottle of vinegar (acetic acid) stolen from the kitchens was another good one. While I was involved in the Dillon MINIGUN trials, we had a fantastic carbon remover stuff that came over with the 10 guns. It was a foamy goo stuff. It took the carbon off like nothing I've ever seen before. It was like magic. We destroyed two guns in the trials andsomeone suggested that this carbon remover stuff might have had something to do with the fine cracking/crazing. I doubt it, but I'm not a chemist

Hope you were wearing rubber gloves when you used it Peter!.......