Sten bfa?

[ickmann]

Looking into joining a re-enactment group and was looking for a blank firing adapter for my semi-auto Sten (Catco). Glanced through the web and could not find anything regarding Sten BFA's. Was there ever such an animal?

Yes, I know I need Peter's STEN book...

Thnx.

Information

Warning: This is a relatively older thread This discussion is older than 360 days. Some information contained in it may no longer be current.

[gsimmons]

They don't make one you have to alter the barrel. Try Atlantic wall blanks site for help/instructions on adapting a barrel.

[browningautorifle]

If you have the capabilities, all you do is make a blank barrel with solid stock. Chamber it for 9mm and drill enough gas vent through for operation. Start with 1/16 drill bit.

[philb]

heres a question

how is the rate of fire worked out with the springs used in any smg ?

is it a softer spring will give less rdspm or a harder spring will give more rdspm ?

or other way round or ????

[Peter Laidler]

Ah, good question. It isn't simply a question of springs but of breech block weight too. Really it is a fine balance between several things. Not least, the ammunition you are using. To be honest, there is no set formula.......... It would take many hours in a class room to get the subject over. And guess what....... Even at the end of several lessons, there will STILL be some disagreement amongst the flock. But if anyone really is interested I'll write up a paper. But guess what............... at the end of it, there'll STILL be some disagreement among the flock. Just as there was with regards cutting gas operated/L1A1/Bren barrels short

[CINDERS]

If I may be so bold Peter never assume all of the flock will question what you say I have said it a 000 times knowledge shared is far more of a benefit to the community here at large that it disappearing down the plug hole so to speak.
I for one will always look at the information supplied, its a bit like say an engineer who has no practical experience with cranes trying to tell me (it has happened) that they will do this and that no sir it wont and have stood toe to toe with them finally showing them in a safe manner the limitations of the said machine despite their slide rule stuff.
You cannot replace the gained knowledge of stuff learned in the field it will just never happen, don't sell the community short by surmising we will all have something against what you say Peter.
Cheers,
CINDERS

[browningautorifle]

a softer spring will give less rdspm or a harder spring will give more rdspm

To add to what Peter says...I've changed a few springs in my time. I was rebuilding an M3A1 Greasegun with new springs as it had none, used the inner butt springs from an FN C1 as I recall. The wire was thicker and coil heavier so it ran at about 1000-1200 RPM through it's 10 rds for test. I had to use a screwdriver to cock it. All were in the air at once... If you add a half a recoil spring behind the existing Sten spring you'll get an increase that will run about 750... There are trades though, ammo consumption, lack of manageability, lack of accuracy...post ammo letdown...

[philb]

so a soft spring lowers rdspm ?

and a strong spring does the opposite ?

[browningautorifle]

Right, stronger runs fast. Weak might not even feed... strong might be a problem too. Best to refer to correct wire dia and coil size.

[Peter Laidler]

But.............. A stronger spring holds the heavy bolt forwards against the cartridge for longer and as such takes far longer to allow the bolt to accelerate rearwards........... And then when the bolt is at its most rearwards position, has it reached the sear............ More complicated than that