I just bought a lynx 12 to SBS
How short should I chop it? Is there some sort of standard?

Also, do muzzle brakes actually work on these and do they make the concussion suck?
It would be much cheaper not to have it threaded externally

Tony Rumore at Tromix did 8" barrels on some of his S17 Saigas. I don't think cutting the barrel is a problem. Getting the short barrel to function with the different ammo IS the problem. Tony wouldn't have been able to get the prices for his guns if anybody could do it. He did a lot of work on the gas systems to get good functioning. I don't know what was involved in his work. I guess what I'm trying to say is if you don't understand the process you may not be successful. Anyway however you go on this project good luck to you. I hope you are successful.

I have shot the Tromix 8 inch S17 and it really is a blast. It functioned with anything it was fed from Walmart bulk 2 3/4" #8s to premium 3" high brass buck and slugs. The one I shot is like the picture below.

So a saiga 12 had two gas settings right?
The lynx12 I bought says it has 4 settings so I’m hoping that makes the SBS conversion more forgiving
I think I’ve settled on 12-12.5”

I don't know if this will help or not as I've never touched a Lynx, but this was my experience SBS'ing a Saiga 12.  I am far from claiming any kind of expertise and hopefully someone much more knowledgeable will come along with better information.  

I can only assume that the gas system in the Lynx is similar to that of the Saiga.  The barrel on my S-12 is right at 11.25" as I was trying to obtain a certain look for the finished shotgun.  I was using a conversion kit from Dinzag Arms that allows you to use standard AK handguards.  The kit included the front site post (uses set screws to anchor it) and the AK74-looking muzzle brake.  To use the muzzle brake I had to re-thread the outside of the barrel which I did myself.  

I already had another S-12 which was picky with different power loads with a full length barrel so when I started working on the SBS I knew that I would have to modify the gas ports as the barrel got shorter in order to have enough gas to cycle properly depending on what loads I wanted to use.  My goal was to be able to cycle high power loads and also lighter low power bird shot loads.  I chopped the barrel in small'ish increments and test fired different loads each time.  If the lower powered loads wouldn't cycle, I would press off the gas block and open up gas ports a little at a time until those loads would cycle.  My gun was a four port barrel from the factory (see example in the photos below - those are not photos of my actual barrel).  Before I was done I had added a fifth port.  I can't find my notes, but I think I first chopped it to about 15" and then a couple more increments until it got to where it is now at 11.25".   Right now it won't cycle the very light loads, but I could probably fix that by opening up a couple of the ports just a little more.   Keep in mind that the adjustable gas plug (at least on the Saiga's) just covers or uncovers the gas ports in the barrel in order to regulate the full power available via the ports.  Once the plug is open, it's open.  If there's not enough gas to cycle loads, you'll have to allow more gas to come through the barrel by enlarging the ports or adding ports if multiple smaller ports are used like on the Saiga.  

Assuming that the Lynx has similar gas ports to the Saiga, I would be pretty confident that you will have to modify the gas system a bit to get it to cycle properly at 12 or 12.5" - unless the gun was way over gassed to begin with.  

My gun showing front end with and without the brake.




Example of Saiga gas ports (not my gun)

I have one just like that, built by Tony. It runs well.

I hate it. When I take it to shoot, every year or three, I go home wanting to sell it. I wish it had about 4 more inches of barrel.

Yamadog has the right idea.  Cut it a little at a time and open/add gas ports to keep it running.  At some point you will realize if you cut the barrel down anymore, there is no way to open the ports enough to keep it running.  Stop at that point.

If you really want it shorter than that, then you will need to move the gas block closer to the chamber and shorten the operating rod.

Keep in mind, the Saiga-12 has issues with dumping a pile of wad fouling into the gas block and clogging up the piston's chamber....it's far worse with some shells than others.  The larger you make those gas port holes, the worse the problem gets.

You may end up pulling the gas regulator after 25 shots or so and dumping out all the wad fouling to keep it running.

Tony Rumore
Tromix

See I told you someone would come along with a lot more experience than me. . . a LOT more.    Thanks Tony!

Test fired the gun today at OEM 19” barrel
Flawless with 75 federal 2 3/4 7.5 shot

I’m excited to get this project rolling

I have one of Tony’s short Saigas, I love it. The fireball from the muzzle brake will remove all of the hair from the back of the hand.

Any update on this? I just got a Lynx myself, thinking it needs to be at 13".  Does anyone offer a cut/rethread service on these?

@guncat
Rose action sports

Waiting on my F1

Awesome, thanks!

I think I settled on 12”

That is just beautiful looking. I love it!

First range trip update: 25rnds of 3” Winchester #2 shot and 2 random Brenneke slugs ran awesome. Choked on federal and Winchester 2 3/4” 7.5 and Remington gun club 8

We’ll see if it actually “breaks in” or if it’s going to be a 3” only gun