Bren MKII to L4 Gas Shield

[Peter Laidler]

PS. Forgot to add BUT if it is the body that is a bit skew wiff, then you might have to rotate the gas cylinder accordingly to allow the locating prong to locate into the slot in the gas regulator. We had a special alignment gauge for this when we were fitting new gas cylinders. But shouldn't be a big problem and fitting a new slightly oversize taper pin should solve the 'problem' - if there is a problem. There's plenty of meat in that area

[Peter Laidler]

Has this project died a natural death C-130 pilot?

[c310pilot]

Nope. My wife and two children went down to the boat for the weekend. Had a nice time watching fireworks and enjoying the festivities @ Harborfest in Norfolk. In the mean time I have a second reamer on order as the first was to small. I got an 0/2 instead of a No1. It should be here in a couple of days and I can hopefully get that pin reamed out. I also had to order a 4" .25 cutter for the feed ramp modifications.

fanallie.MOV - Google Drive


I wish I could photograph like this:

All sizes | Norfolk, Virginia on the Elizabeth River | Flickr - Photo Sharing!

All sizes | Fireworks in Norfolk, VA | Flickr - Photo Sharing!

[Peter Laidler]

Did you ever establish exactly what was out of alignment? Was it the whole front part of the body or just the gas blast plate alignment locating lugs worn?

While you wish you could take photos like that, mere mortals like me just wish we could LIVE in a place like that!

[c310pilot]

The lugs on the gas shield are worn. I tapped the gas shield with a brass hammer and the thing rotated an 1/8". I now have a .06 gap on one side of the lug after it moved. I will take a picture to clarify. Just got notice the reamer will be here this afternoon. Unfortunately my wife is in California (we live in Virginia) for work today and tomorrow and I got stuck with the little ones. If I can get them to bed early enough maybe I can get out in the shop for an hour or two.

[Peter Laidler]

That's amazing that it could be that far out of true radially! We had a gauge (that I'd photograph if I was anything but a total computer illiterate) that slipped into the new gas cylinder that also aligned with the barrel alignment rib on top of the body (or inbetween the ears on the Mk2 type), the ears while also aligning the gas cylinder prong while you reamed (or re-reamed it usually....) the taper pin hole. Usually you'd wait until you had half a dozen new gas cylinders to fit and give them all to one bloke to do. Generally speaking it was a crap job, so the bloke that had usually been a bit late or better still, a bit late AND cheeky with got the job to do!

The good bit was that it was a couple of hours on the range afterwards. Ask me about the depression pit test. That was always good fun!

Keep us informed. Interesting thread from the Bren re-welders point of view

[c310pilot]

Well I finally got the gas tube removed. Ended up reaming the pin out and then using a steel block tapped it out using the gas shield. To install the new gas shield I polished the gas tube with super fine scotch bright and used some mil-comm to lube it before reassembly. The assembly is snug but serviceable now and the new taper pin will secure everything nice and tight. The taper pin reamer used was a No1.


IMG_9026 by c310pilot, on Flickr


IMG_9027 by c310pilot, on Flickr


IMG_9034 by c310pilot, on Flickr


IMG_9033 by c310pilot, on Flickr


IMG_9030 by c310pilot, on Flickr


IMG_9031 by c310pilot, on Flickr

[Peter Laidler]

Just like that.............. Brilliant!

Added later....... Pic 4 shows exactly what you speak of. The darkened silhouette of the face of the body distinctly shows the offset/cant against the blast plate. I'll get a photo of the gas cylinder alignment gauge and ask Badger to put it up. Better still, get my son to give me a tutorial.......

[c310pilot]

Just like that.............. Brilliant!

I would love to see that alignment tool. As of note, I found gauling in the insert area of the body where the gas tube was forced in orginally. This undoubtly caused extra friction. This made the use of the bipod as wrench unsuccessful and started to round the bipod locating lugs on the gas tube (hence the polishing). If the press fit was clean, I could see how this approach would work.

[tr63]

to find .