Bren uncommanded automatic fire event.

[browningautorifle]

When I had my first BAR, I'd go through about 300 rds of .30 cal in about 15 minutes. Then I'd change to the M1, Johnston automatic and Carbine...M14...1903 rifle...go home empty and start loading again. 750 isn't such a far reach...really.

[Gopher]

I have 2 loads I use in both Enfield Rifles and the semi-auto Bren.

All use HXP brass and Winchester WLR primers
The 150 grain FMJ-BT load is 44.5 gr of RL15 (surplus military bullet)
The 174 grain FMJ-BT load is 40.5 gr of RL15 (Hornady is the bullet mfgr)
OAL is 3.025 in both cases.
The Bren is hard on the brass

[browningautorifle]

The Bren is hard on the brass

It's almost worth it though, isn't it?

[5 Commando]

I have 2 loads I use in both Enfield Rifles and the semi-auto Bren.

All use HXP brass and Winchester WLR primers
The 150 grain FMJ-BT load is 44.5 gr of RL15 (surplus military bullet)
The 174 grain FMJ-BT load is 40.5 gr of RL15 (Hornady is the bullet mfgr)
OAL is 3.025 in both cases.
The Bren is hard on the brass

Thanks for these, very helpful.

[Peter Laidler]

Except for the ejector that stakes the primer, I don't really know why the Bren will be particularly hard on the brass. It has a gentle primary extraction feature, a LARGE radial area by the extractor to grip and grip VERY tightly (another good feature that prevents tearing the rims away). The only other feature you could consider 'hard' or harsh is that when the case is ejected it can come around and ding against the rear underside of the piston extension and put a small crescent mark in the case. THIS MEANS HARSH EJECTION so you could drop the gas down one hole. But even then, this crescent mark won't(?) make any difference to subsequent reloading and firing.

Just me thinking on my feet about the action and the previous comments

[5 Commando]

Except for the ejector that stakes the primer, I don't really know why the Bren will be particularly hard on the brass. It has a gentle primary extraction feature, a LARGE radial area by the extractor to grip and grip VERY tightly (another good feature that prevents tearing the rims away). The only other feature you could consider 'hard' or harsh is that when the case is ejected it can come around and ding against the rear underside of the piston extension and put a small crescent mark in the case. THIS MEANS HARSH EJECTION so you could drop the gas down one hole. But even then, this crescent mark won't(?) make any difference to subsequent reloading and firing.

Just me thinking on my feet about the action and the previous comments

Understood. Ta the clear explanation, was not sure where the crescent marks were coming from, but now I see. I re-dialed the gas regulator one stop down on the strength of your advice and find the brass less worked. About 10% of the cases were getting their necks dented, but with less gas almost none are deformed. If you get the time Captain Laidler, could you define and explain primary extraction for me, especially with respect to the Bren? Thanks, Mike.

[Peter Laidler]

Brens do distort the case necks but this is when they hit the floor under the gun. That is an easy cure. As for the primary extraction......... It all starts when the piston extension moves rearwards for the first 1/2" or so and a ramped cam at the front of the piston extension tightens the extractor stay in the breech block so that the stay bears hard on the actual extractor. Now, when........... I have described this feature a couple of times before so can I ask if someone who logs these things can resurrect it so that I don't have to repeat it all again.......... Anyone........?