Svt-40 firing 2 round burst
- Thread starter Ced1942
- Start date
In what position are you shooting in? Semi auto rifle in a heavier recoiling caliber could do that if you don’t hold trigger down after shot ( this isn’t a bolt action).Check to make sure the sear and reset are working by dry firing, holding the trigger down then racking the charge handle back and see if trigger resets. My guess it may be shooter induced.
justinb1981
Regular
- Location
- Hamilton, Ontario
Mine did that a couple times. Ended up being shooter error. Wasn't holding it tightly into my shoulder and was being too light on the trigger. It recoils enough that the trigger resets and it shoots again when it pushes back into your finger
Big bore dinosaur
CGN frequent flyer
- Location
- NORT OF COW.TOWN.EH
Happens in my tavor when I really creep the trigger home.. and hold soft.. . . Once in a blue moon
when I snug up my grip dosent happen.
when I snug up my grip dosent happen.
- Location
- Blaster land, Okanagan BC
Maybe it’s trying to gender identity as an AVT!
- Location
- Central AB
2 round bursts eh! Normally you pay extra for that option.
Most likely, the rifle is over-gassed. Reducing the amount of gas being used will remedy the situation.
There are 2 types of gas systems using pistons: the type which takes a constant amount of gas from the round being fired and VENTING excess gas before the piston hits the Bolt Carrier (as in the FN-FAL) and the system in which the amount of gas getting TO the piston is regulated before it gets there. This latter is the type of gas system used on the SVT-40.
What is happening is this: the first round is fired by the Hammer striking the Firing Pin on the Bolt, completely as usual. The round fires, the bullet passes down the bore, passing the Gas Port. At the Gas Port, TOO MUCH gas is directed to the Piston. The Piston moves backward, hitting HARD against the Bolt Carrier, which then moves rearward very fast, lifting the Bolt from its seat in the Receiver. The Bolt and Carrier then travel rearward in the Receiver. When Bolt and Carrier reach the rear end of the trough-shaped Receiver, they are going MUCH TOO FAST. The Bolt Carrier compresses slightly, the Receiver stretches slightly, then all that stored energy releases itself at the beginning of the counterrecoil stroke, actually BOUNCING the Carrier and Bolt forward at a very high velocity. This sounds crazy until you understand that Steel has a HIGHER modulus of elasticity than RUBBER!
The Receiver returns to its correct shape, throwing the Bolt Carrier with the Bolt forward at a rate far beyoind what the rifle was designed for, the Carrier itself undoes its own compression..... and the action returns to battery position MUCH faster than it should. The Bolt strips the next round from the Magazine, chambers it.... and the Firing Pin drifts forward to set off the Primer and fire the Cartridge EVEN THOUGH THE HAMMER IS BEING HELD IN 'COCKED' POSITION.
This is a serious overgassing of the action.
The next stage -- at which you have not yet arrived and possibly will not -- is that which results in the destruction of the rifle. The Globco 555, made FROM an SVT, featured a shortened gas system which drew gas from the Gas Port at MUCH higher pressures. This rifle has been known to operate at SO MUCH overgassing that rifles have fired entire magazines of rounds WITH THE BOLT LOCKED ONLY ON THE FIRST ROUND.
You do not want this to happen!
Get a Tokarev gas-adjustment tool and adjust the gas so that the empties come out of the rifle and land as CLOSE TO THE BENCH AS POSSIBLE.
The rifle is now in a SAFE condition and, for an added bonus, it will now shoot at its most-accurate level AND with the minimum-possible recoil.
Good luck!
There are 2 types of gas systems using pistons: the type which takes a constant amount of gas from the round being fired and VENTING excess gas before the piston hits the Bolt Carrier (as in the FN-FAL) and the system in which the amount of gas getting TO the piston is regulated before it gets there. This latter is the type of gas system used on the SVT-40.
What is happening is this: the first round is fired by the Hammer striking the Firing Pin on the Bolt, completely as usual. The round fires, the bullet passes down the bore, passing the Gas Port. At the Gas Port, TOO MUCH gas is directed to the Piston. The Piston moves backward, hitting HARD against the Bolt Carrier, which then moves rearward very fast, lifting the Bolt from its seat in the Receiver. The Bolt and Carrier then travel rearward in the Receiver. When Bolt and Carrier reach the rear end of the trough-shaped Receiver, they are going MUCH TOO FAST. The Bolt Carrier compresses slightly, the Receiver stretches slightly, then all that stored energy releases itself at the beginning of the counterrecoil stroke, actually BOUNCING the Carrier and Bolt forward at a very high velocity. This sounds crazy until you understand that Steel has a HIGHER modulus of elasticity than RUBBER!
The Receiver returns to its correct shape, throwing the Bolt Carrier with the Bolt forward at a rate far beyoind what the rifle was designed for, the Carrier itself undoes its own compression..... and the action returns to battery position MUCH faster than it should. The Bolt strips the next round from the Magazine, chambers it.... and the Firing Pin drifts forward to set off the Primer and fire the Cartridge EVEN THOUGH THE HAMMER IS BEING HELD IN 'COCKED' POSITION.
This is a serious overgassing of the action.
The next stage -- at which you have not yet arrived and possibly will not -- is that which results in the destruction of the rifle. The Globco 555, made FROM an SVT, featured a shortened gas system which drew gas from the Gas Port at MUCH higher pressures. This rifle has been known to operate at SO MUCH overgassing that rifles have fired entire magazines of rounds WITH THE BOLT LOCKED ONLY ON THE FIRST ROUND.
You do not want this to happen!
Get a Tokarev gas-adjustment tool and adjust the gas so that the empties come out of the rifle and land as CLOSE TO THE BENCH AS POSSIBLE.
The rifle is now in a SAFE condition and, for an added bonus, it will now shoot at its most-accurate level AND with the minimum-possible recoil.
Good luck!
I have the tool and im 100% sure overgassing is not the issue. I actually started down to 1.2 gas setting. Rifle cycle fine recoil is pleasant its really great other than the 2 shot going at once. Got up to 1.3, same issue. Went up to 1.5 and now it wont pickup the next round but the sear does reset since it goes clic.
As for the one saying to get it fix, thats what i want but i have no gunsmith in town so im looking here first as a first try if i can narrow down to a faulty part and switch it.
I had the same problem in mine,taking a close look at the trigger group it became obvious that someone in the past had done
a "trigger job" on the hammer,only small groove left for the sear to engage.
Solution was to replace the hammer,problem solved,cycles perfectly on 1.2 gas setting,brass comes out with just a minute dent
on the side.
gewehr76
CGN Ultra frequent flyer
OP. You probably have weak Firing Pin spring in the bolt. Its critical that the FP stays below face of the bolt when rifle cycles. If spring of FP is weak, inertia of the bolt closing on second round allows FP to protrude past resistance of the spring and reach the primer, thus firing second round without pulling the trigger. You have to go to the source of the problem, remove FP from the bolt, clean and inspect FP channel in the bolt, inspect for abnormal wear and sand areas of FP that can cause it to bind and stay protruded past bolt face.
I had similar issue with one of my SVT when using reloads with soft primers, bursts of 3-4 rds were common. After swapping FP and spring in the bolt problem went away.
I had similar issue with one of my SVT when using reloads with soft primers, bursts of 3-4 rds were common. After swapping FP and spring in the bolt problem went away.
Both of these make sense i will pull it appart later tonight and see if either part could be at fault. Thanks for the info guys
