Bren newbie: Rimlock woes

Hi,

I'm just starting to learn a new (to me) Bren. It's a remanufactured transferable full auto Inglis Mk1*.

The issue I'm having is rimlock as the magazine is feeding the rounds while firing. I've tried HXP reloads, S&B reloads, and old Brit surplus .303. I very carefully load the mags to make sure I don't lock the rims during loading. I've also tried a few different magazines.

I've found that the gun needs to be on gas setting 3 to run if that might indicate a related issue.

Any tips on what I should start looking at to resolve this?

Thanks!

Matt

Are you saying that dispite the mag being loaded rim in fron tof rim, that the rounds are some how jumping over the rims to lock the top round behind the next?

I have dealt with one or two Bren guns in my time but like BP above says, and I reiterate, you'll have to elaborate on exactly what you mean by rimlock......... Ain''t a term I've ever heard of in relation to Bren guns. And having been in the Army, I've heard a few terms in relation to them. Not all good either! Bollocks when you have to run with one......, but not rimlocks!

BP nailed the description. I load the magazine being very careful to make sure that it's loaded with the rim of one round properly in front of the rim of another round.

During firing, the rim of the round about to be fed into the chamber somehow jumped behind the rim of the round higher up the magazine. This causes a malfunction because the round can't feed since the case rims are 'locked'. It's never the first round fed out of the magazine but a round higher up the magazine.

I've tried a few different magazines and have had the same issue. This isn't making sense because it's such an uncommon problem with the Bren. I'm hoping that it's some stupid newbie mistake that everyone else knows already.

I know it's very difficult to diagnose this over the web so I very much appreciate any ideas you have. Thanks you!

When your Bren jambs up, where does the breech block stop. This might seem a daft question - and the obvious answer would be '....... behind the base/rim of the top round in the magazine stupid.....'. But this isn't necessarily always the case.

What you have might APPEAR or SEEM to be a rim-behind-rim stoppage but could also be something else. Incidentally, your gun should run quite happily USING NATO MK7 BALL on gas setting 2 - the second smallest hole.

Thank you very much for taking the time to help (I've really enjoyed your books by the way).

It's going to be a week or so until I can shoot the gun again so I'll post back with pictures of the malfunctions. My reloads could be suspect for operating a Bren. I did use standard reloading data and common military semi-auto rifle powder.

The surplus 303 I have should be more informative for diagnosing this so I'll get the headstamps off it to post. It's tracer or incendiary and is definitely cordite ammo. I mentioned the #3 setting because I've read your other posts that the gun should run on #2.

With the current ammo shortages I'm out of luck with trying to get MK7 ball to test with. Shipping ammo to Alaska compounds the problem but I'll ask around my shooting club to see if anyone has some available locally.

Would you have any suggestions on parts I should try changing out or tests I should try when I next shoot it?

Thank you for helping me.

my friend has some mk7 that came into the US awhile back that he volunteered for testing. i'm not sure of the manufacture date yet but i'll test a couple of magazines with this ammunition also.

Saying that ithappens with all of your magazines leads me to ask whether your magazines are in fact .303" magazines. Check this too!

Will do. I think I have a book that will help me make sure. :)

I'm also going to check the over all length again on my reloads. If they're shorter than maximum it might be causing issues by allowing them to move in the magazine?

The MK7 ammo and photos will be telling. I'll report back with better information after I shoot it in a little over a week.

Can you post a photo of the mags your using, they could be ZB39 mags. If you can't get to the range what happens if you cycle the rounds through by hand?

Hey................... DANGEROUS PRACTICE! Never but NEVER cycle rounds through a Bren unless they are DRILL or Armourers dummy rounds. It fires the moment full locking is complete.

I'm away from home and won't be back until Friday. I should have pictures and a shooting report by next week. Thank you for your continued interest to help.

Quote:

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Originally Posted by Peter Laidler

Hey................... DANGEROUS PRACTICE! Never but NEVER cycle rounds through a Bren unless they are DRILL or Armourers dummy rounds. It fires the moment full locking is complete.

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My bad, I should have clarified with 'Drill rounds'. Assumption is the mother of all f**k ups as they say.

I traded ammo to a friend and he gave me a mix of three different kinds of factory surplus ammo. As some of you may have suspected my reloads were the problem. I was using hornady 174 grain FMJ projectiles that I crimped low on the ogive. This results in a shorter OAL than the military ammo which then allows the rounds to move within the magazine and rim lock the gun.

It was a great day on the range. Thank you all that took the time to help me.

Happy shooting.