r/canadaguns • u/starw24-ps4 • May 01 '26

Fix my gun SKS Undergassing Fixes?

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I have received an sks that has a barrel which has been cut and crowned down to 18.6”. The owner told me it has been short cycling, which from my research says could be due to either the gas system being loose or more likely due to the dwell time in the barrel now being shorter.

I am going to bring this gun to the range with a bunch of spare parts for a day to start troubleshooting it, and see if I can get it to work. My current fix steps are below, am I missing anything? Do you guys have any tips to help this cycle? 18.6 Sks pictured with a cherrywood stock for attention.

  1. Try it as normal, if it doesn’t work then -

  2. Swap gas tube to second one

  3. Tape front end of gas tube in case of gas loss

  4. Swap long gas pistons

  5. Swap short gas piston and spring

  6. Swap recoil spring

  7. Swap bolt and carrier

  8. Try a detachable mag and new ammo?

Worst case if it still doesn’t run, I may look into either getting a lighter recoil spring or cutting down an extra one to see if that lightens the bolt. Thanks!

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u/AresV92 May 01 '26

Just to be safe if all else fails before you sell it or relegate it to a parts gun see if you can run a bronze pipe cleaner or wire through the gas port. Unlikely, but could be fouling restricting gas flow.