Deactivated Bren Gun Problem

Hi guys,

I have a Deactivated 1942 Enfield made Bren Mk1. I took the recoil spring out of it on Sunday, as I wanted to see how the stock came off as I was thinking of putting a finish on it. The recoil spring was covered in grease, so I cleaned it over Monday and Tuesday, and then I oiled it yesterday afternoon. I put the stock and spring back into the Bren and screwed the cap onto the spring. I cocked it once, and it didn't feel quite right, but I think that was just the recoil spring aligning. I cocked it a second time and fired off the action, fine. I did it a third time without a problem. I then tried to cock it a fourth time, and I couldn't cock it. It was jammed. I stripped the Bren, and the first thing that I noticed was that the Bolt and Carrier didn't slide out of the receiver. I tried to move them out, pull them out, push them out, but they wouldn't come out, there's about 2cm of play back and forth. I've been pushing and pulling the parts over and over again. I've sprayed a lot of oil into the working parts in a hope that it may dislodge any obstruction. The problem is that the bolt is not sliding down below the raised part of the receiver, the mag well effectively. It is just ramming itself into the metal, and not lifting itself at all. I think something must be obstructing the travel of the bolt on its tracks, on the carrier. I did a Google search and could not find anything like this, I contacted a workshop who said they had never seen anything like it and I contacted the dealer who said he would have a look at a few of his Brens to see if he could come up with a solution. I was wondering if this problem had happened to any one else? and if any one here can help.

Thanks.

Attachment 43494

You effectively have the bolt in the locked position but as you dont have a locking shoulder fitted (Being a late deac) the bolt has moved into the locking shoulder recess. You need to tap the bolt forward, not the bolt carrier, just the bolt. It may take the bolt carrier forward too but that is fine to start with, get everything back to the correctly locked position and it should all free up.

Here are some photos to help show whats going on, the top one shows the bolt has ridden up the locking cam and is 'UP' or the locked position, the lower photo shows the bolt in the 'DOWN' or unlocked position.

https://www.milsurps.com/images/impo...d0c1547e-1.jpg

https://www.milsurps.com/images/impo...dfd84254-1.jpg

The reason this has happened as described by BP. Is that on later Deacts, part of the 'Updated' Deactivation specs. Require that a portion of the Lug that the breech block sits over. Has to be ground out. This in effect remove an area that would strike the firing pin on a Live firing example. On the deact, this effect has been nullified due to the metal removal on the hammer face of the piston post. It is simple to rectify as also described by BP. But use a BRASS drift, so that you don't damage anything when using the 'Birmingham Screwdriver'! (Hammer) :D

Thanks for the help guys, I'll give it a go later. I thought it might have been something simple!

Just a thought chaps............ But surely, if the locking shoulder is taken out of the currect dewat Brens it shopuld be academic and NOT the cause. Because regardless of whether it's there or not, the unlocking cam of the piston post will STILL bodily/forcibly drag the rear of the bolt down out of engagement with the underside of the body, regardless of where it is supposedly jammed up..... No?

And further........., the L54/L55 DP Brens had the locking shoulders removed and they didn't jamb up so far as I know as I wrote some of the technical spec for them as a project prior to standardisation of the breed!

Okay, so I've been tapping the bolt forwards for about 45mins now and nothing has moved. I think BP is right in saying that the bolt is locked up. I just don't know whether tapping it continuously is doing any good, or just doing damage somewhere. Any ideas?

Sorry to butt in, it appears to be jamming from the sound of it on the runner that the bolt sits on, what we used to call the runner that needed to be engaged "By the aircraft landing properly on the carriers deck" that won't mean anything to those that were'nt trained on the Bren, but if this is not held in position as it is slid into the carrier, it will jam naturally.

A bit of TLC in needed with the correct hammer at the right place, sorry I can't beam myself up to assist.......persevere it will shift without damage, as it clearly was working OK before it jammed it self.
Hope that helps
Gil

So in short the Bren you have there has had the carrier shaved causing the block to have less purchase in the machined groove then it would on a firer, for good reason obviously as its a DEAC.
Therefore the block will naturally ride looser then normal if cocked to excessively. Hope that sounds reasonable.

Quote:

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Originally Posted by Peter Laidler

Just a thought chaps............ But surely, if the locking shoulder is taken out of the currect dewat Brens it shopuld be academic and NOT the cause. Because regardless of whether it's there or not, the unlocking cam of the piston post will STILL bodily/forcibly drag the rear of the bolt down out of engagement with the underside of the body, regardless of where it is supposedly jammed up..... No?

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It should do but I suspect that the piston post has maybe bent rearwards due to weakening by the deac process. I have seen a number of examples where they have removed so much of the hammer section that there is only about 1/4" metal remaining. Perhaps it has bent rearward stoping the bolt traveling forward and unlocking and thus locking into the locking shoulder recess. I reckon he needs to get a bigger hammer.

Thanks for the help guys, the BREN is fixed! I took a sledgehammer and crowbar and had to hammer the bolt carrier out of the receiver! The problem was that the spring holding the claw, that holds rounds in place on the breech face, had dropped down from the breech block and was preventing the breech block from moving correctly.

Something DEFINATELY wrong somewhere......... The extractor stay, being spring loaded and riding in a tapering slot should/will always be under load and impart that load onto the extractor that is never free to free itself from the breech block. Oh well..........

If you are coming to the war & Peace show in July at Folkstone Racecourse. I will be there with my Armourers Display, working 'In the Field'. If you (Or any forum Members/Friends/Collegues) are attending & need some help or Technical assistance. I will be located to the Far RIGHT of Fort Bastion (As you are looking at it from the front) All correct tools, Gauges, equipment Etc. Will be there to effect repairs & Modifications where possible. 17-21st July. :thup:

Quote:

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Originally Posted by Peter Laidler

Something DEFINATELY wrong somewhere......... The extractor stay, being spring loaded and riding in a tapering slot should/will always be under load and impart that load onto the extractor that is never free to free itself from the breech block. Oh well..........

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That may be the problem Peter, some of these post 95 deactivated Brens have that slot ground off. So to really screw things up, they remove the piston (Fair enough) and then weld up or slot the thread. They grind off the track for the extractor, grind down the piston post and sometimes they butcher the carrier by cutting through one side or by partially cutting both sides to weaken it. And to top it off, its not always done neatly like an engineer would, they just attack with a grinder and it just looks like a childs work.