Pretension on a Suomi drum

[ScottinTexas]

How many clicks of pretension should a Suomi drum have?

 

[gun.bro]

YouTube says 8

 

[Offmarksman]

Some say 3 complete revolutions some say 4. I have had some feeding issues when I only did 3, but have never had a failure with 4.

 

[llamasabound]

Yes. I like four as well, for the same reasons.

 

[ScottinTexas]

Thanks guys. I remembered that video but apparently my search terms were inadequate.

 

[wrhk33]

I learned the following the hard way. I was new to the drums and watched the video on how to totally strip them and reassemble them. For me it was a great video.
After having some problems with my drums I took one apart. The preload was only about 1.5 to 1.75 turms. I checked another, about two turns. I now take all new ones I get apart
to make sure it has at least three turns.

 

[Gaujo]

Are you taking about how many turns after loading it or something else?

 

[gun.bro]

He asked for clicks. Which I think is 4 per revolution?

 

[Galil#1]

It's eight (8) actual clicks and works perfectly well here 100%. Call it whatever else makes ya happy friends.

 

[RevolverJockey]

Suomi Clicks

It should be 4 clicks of pretension before you reinstall the follower of, then the mag should take 8 more clicks to load fully. I have one or two that are mismatched or reworked that only get 7 clicks and 65 rounds, but if needed the plate can be manually rotated to load to full capacity (in the off chance 65 rounds isn't enough, lol).
Lee

 

[JohnnyE]

It should be 4 clicks of pretension before you reinstall the follower of, then the mag should take 8 more clicks to load fully. I have one or two that are mismatched or reworked that only get 7 clicks and 65 rounds, but if needed the plate can be manually rotated to load to full capacity (in the off chance 65 rounds isn't enough, lol).
Lee

I think in terms of revolutions. How many clicks make one complete revolution?

 

[Uncle Billy]

4 clicks makes 1 complete revolution.

I'm here to tell you the SUMOI as well as the PPsH drums can take a lot of revolution....when I made my PPS-43 drums, for the 7.62 and 9mm PPS-43, and MP5 drum, I pre-tensioned it with 4 complete revolution(16 clicks), to give that OMPF so the rounds would feed up the feed tower. so my drums have a total of 24 clicks

I originally tried 2 then 3 revolution (8 and 12 clicks) pre-tensioning, but it just didn't feed the rounds up reliably or kept up when I rapid fired the guns.

now, 2 revolution (8 clicks) pre-tensioning is more the adequate for what you guys need, since your rounds don't have to travel up a feed tower

 

[JohnnyE]

4 clicks makes 1 complete revolution.

I'm here to tell you the SUMOI as well as the PPsH drums can take a lot of revolution....when I made my PPS-43 drums, for the 7.62 and 9mm PPS-43, and MP5 drum, I pre-tensioned it with 4 complete revolution(16 clicks), to give that OMPF so the rounds would feed up the feed tower. so my drums have a total of 24 clicks

I originally tried 2 then 3 revolution (8 and 12 clicks) pre-tensioning, but it just didn't feed the rounds up reliably or kept up when I rapid fired the guns.

now, 2 revolution (8 clicks) pre-tensioning is more the adequate for what you guys need, since your rounds don't have to travel up a feed tower

Thanks, UB!

 

[Offmarksman]

If there is not enough tension, the rounds won’t feed fast enough, depending on your rate of fire. If you have feeding issues, clock it another full turn. I was having problems with mine a few years back. I had them clocked at 3 turns. I posted my issue on UT, and Vegas (God Rest his Soul) told me to clock them to 4 turns. He said he sold thousands of them and clocked them all to 4 turns.

 

[Hey...]

I have several nice condition drums that needed disassembly for initial cleaning when I first took ownership.

Shooting I found the drums with 2 revolutions preload would jam the last round or two, and the ones with 3 revolutions were 100%.

This was found out upon disassembly, counting as I was in detective mode. After making them all 3ish revolutions of pretension they are all 100%.

Note that drums don’t make for perfect revolutions, some of mine are 3.25 or 3.5 revolutions, so long as 3+ I’ve been satisfied with feeding all rounds.

Again, Thanks to Lage for making the 31c.

 

[Uncle Billy]

.

Again, Thanks to Lage for making the 31c.

the businesses and folks who have SUOMI drums are really happy as well, wasn't too long ago you couldn't give those drum away, let alone get people to shell out 15 or 20 bucks for one ........now they are 100+ bucks and people are clamoring for them

 

[Hey...]

I appreciate the effort spent making these drums. We all want them surplus cheap, and some purchased them early enough when imported at a low price.

I admire the quality of the Suomi drum even at today’s prices.

The drums in my mind are much more valuable than the coffin mags, but the market has final say.

 

[Galil#1]

Indeed even at current $100+ a pop, they cannot be made today with the same level quality at this price point IMHO.
Such a rich and well functioning piece of history as well!

 

[SecondAmend]

4 clicks makes 1 complete revolution.

I'm here to tell you the SUMOI as well as the PPsH drums can take a lot of revolution....when I made my PPS-43 drums, for the 7.62 and 9mm PPS-43, and MP5 drum, I pre-tensioned it with 4 complete revolution(16 clicks), to give that OMPF so the rounds would feed up the feed tower. so my drums have a total of 24 clicks

I originally tried 2 then 3 revolution (8 and 12 clicks) pre-tensioning, but it just didn't feed the rounds up reliably or kept up when I rapid fired the guns.

now, 2 revolution (8 clicks) pre-tensioning is more the adequate for what you guys need, since your rounds don't have to travel up a feed tower

I've got a couple of the Vector Uzi drums that are Suomi drums with an Uzi mag feed tower. One is the late version with nylon strips on the inner wall and the other does not have the nylon strips. Both have dummy rounds, not cylinders, for the feed tower fill string. Both work with only 8 clicks, same as the bare Suomi drums that I use in connection with another application.

MHO, YMMV, etc. Be well.

 

[RevolverJockey]

Are you guys saying 2 revolutions before you reinstall the followers, then another 8 clicks to fully load, or you are preloading 3 revolutions prior to installing the follower?
Lee