Subsonic 7.62x39

[Monirh]

I tried Trailboss in 7.62x39 with 124gr FMJs. The velocity was fine but the action would not cycle completely.

I am thinking of trying a SLOOOW burning powder. I have some Vhitavouri N165 laying around. It's one of the slowest powders you can buy.

Am I headed down the wrong road with the slow burning powder?

 

[Ledzep]

Heavy pills (as heavy as will stabilize) and the slowest powder that will allow you to fill the case or have a slightly compressed load will be your best bet.

 

[Monirh]

I tried Trailboss in 7.62x39 with 124gr FMJs. The velocity was fine but the action would not cycle completely.

I am thinking of trying a SLOOOW burning powder. I have some Vhitavouri N165 laying around. It's one of the slowest powders you can buy.

Am I headed down the wrong road with the slow burning powder?
https://www.icrfq.com/

Thankss guys for information.

 

[mdmp5]

I didn't know subs will ever cycle the action

 

[littlehendrick]

For AK's I have had two powders work. Accurate 5744 and IMR 4227 both will work. Ran it in conjunction with LR Magnum primers, and a 180 Sierra for that were .311. Stable to shoot through a can, and cycle the action. Quite the fun project. I don't have the exact numbers for powder charge, but I remember I balanced two loads I found online, then worked down to subsonic.

 

[biffj]

really slow powders are a bad idea in subsonics loads. The idea is to push the bullet out of the barrel with a faster burning powder that will burn completely and pressures start dropping quickly. The idea being that sound is lower when muzzle pressure is lower. As Ledzep noted the slowest powder that will cycle is usually about right. Running really light bullet makes little sense for subsonics. If your intent is to actually use the thing to cause damage the heaviest bullet you can shoot will carry the most energy. It usually gets you the quietest report as well. The heavier bullets will use more of the energy in the powder gas and will allow you to keep the pressure higher at the gasport for function. Lighter bullets don't need as much pressure to pop out the barrel and so pressure will be lower at the port thus making it more difficult to make things cycle.
Lastly, AKs have huge gasports and dump a lot of gas there making a lot of noise.
Hope something there helps

Frank

 

[317millhand]

Try 11.4 grains of imr4227 behind a 180 Sierra