Aluminum Bronze Sten Breech Block

[Vincent]

OK, what don't I know? What is the benifit of a higher rate of fire with a suppressor?
Of course I guess I should talk since I have a suppressed MAC 10, 9mm, but then I don't know of any way to slow the MAC down or I might.
Sarge

To add to a little what Peter said. The gun takes standard supersonic ammunition, but the bullet never reaches subsonic speed. To achieve this the barrel has several vent holes where the expanding gas is bled off into two chambers. By bleeding the gas off this way the pressure is kept down to the point where the bullet stays below the speed of sound. It’s this lower pressure that requires the lighter breech block, because there’s not enough energy remaining to push the mass (weight) of a standard breech block back onto the sear.

Peter wrote the book on the Sten. It’s the best resource I have for my Sten recreations. I reference it and his book on the Sterling VERY often. They are so packed with information that’s impossible to remember it all, and I’ve read them cover-to-cover several times. I highly recommend them. They are not just technical references. They are entertaining too. I often laugh out loud as search for something.

So, if you use it with standard ammo in a standard gun, you get a higher rate of fire. These are all meant to operate with the parts as issued. I once made up a set of drive springs for an M3 greasegun using the butt springs from a Bren. When I touched off, it sounded like an Ingram...ran about 1000 RPM instead of 300. Neat.

Yes, you do get a higher ROF and you do need a stronger return spring, or a buffer. The higher energy has to be absorbed somehow or the breech block is going to hammer the endcap.