7.62x39 subsonic load data......

[Grendelhunter]

Looking to do some sub loads in 7.62x39. not finding much info. What say you all?????

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[osprey]

I might be able to steer you in the right direction with more info. What grain weight bullet do you want to use? What platform, gas gun or boltie? Do you expect it to cycle if a gas gun?

 

[Grendelhunter]

174 serria hpbt. AR platform. Hoping to cycle with adjustable gas block and potentially a suppressor way down the road. 10.5 barrel carbine length gas system.

 

[osprey]

I would try 13 gr of 5744 to start with that bullet. Using a chrono work down until you get your desired subsonic speed. You should end up in the 11-12 gr range and has a good chance of cycling action.

 

[Grendelhunter]

What are your thoughts on accurate 1680? also have 335 and 3n38 on hand.

 

[osprey]

Also before shooting through a can, shoot the load at close range through paper and look for clean holes to prove stability. 1-10 twist should stabilize this bullet at sub speeds but always better safe than sorry as baffle strikes are quite common.

 

[osprey]

1680 should work also but I have never tried it for subs in 7.62x39 so you are on your own for a start load. Good luck

 

[Grendelhunter]

in doing the math, which i suck at......
starting loads as follows
125 grain 311, 25.0 gr. 1680
150 grain 311, 21.2 gr 1680

so i would think 175 grain 311 should be about 17.4 gr start point and work down.
or am i looking at it wrong?

 

[osprey]

16-17 gr of 1680 sounds about right to start.

 

[osprey]

@Grendelhunter, did you have any luck with 1680 subsonic?

 

[ORhutner]

@osprey any guidance on where to locate 195gr or heavier .310 - .312 bullets? Hard cast lead would be fine. Intended use is in a cz527 x39 running suppressed. Would also appreciate any recommendations on powder with an eye towards 80% or better fill of the case.

 

[Grendelhunter]

@Grendelhunter, did you have any luck with 1680 subsonic?

I've got my loads ready, just need to find time to head out to the plantation range where I can rent a Chrono.

 

[osprey]

@osprey any guidance on where to locate 195gr or heavier .310 - .312 bullets? Hard cast lead would be fine. Intended use is in a cz527 x39 running suppressed. Would also appreciate any recommendations on powder with an eye towards 80% or better fill of the case.

I think Imr 4198 will get you close but probably have to go up to a 220gr bullet to approach that fill capacity. Trailboss at 90-100% fill will work but I have always got inconsistent results with it myself. Not sure where to point you on 220 gr. cast bullets. I use to get coated cast 220gr. bullets from leather head bullets which sold or morphed into Gallant bullets. You might try them.

 

[osprey]

Just looked it up, they still have them but now advertised as 225gr.

.30 Cal 225gr

.30 Cal 225gr, Polymer Coated, Cast Bullets using Hi-Tek Coating. Competition Grade. Match Grade. Subsonic 300 Blackout.

gallantbullets.com

They are sized to .310

 

[ORhutner]

Just looked it up, they still have them but now advertised as 225gr.

.30 Cal 225gr

.30 Cal 225gr, Polymer Coated, Cast Bullets using Hi-Tek Coating. Competition Grade. Match Grade. Subsonic 300 Blackout.

gallantbullets.com

They are sized to .310

Awesome! Thank you very much!! Don't have any trailboss but have been looking for it for some time to try with some other loads. I do happen to have 4198! Hopefully 4198 does the trick as I load a handful of other cartridges with it and prefer to keep the powder variety to a minimum as much as possible.

 

[Grendelhunter]

well shoot..............
got all loaded up and ready to head north to the plantation gun range, decided to call with a couple quick questions. appears that the chrono they rent is busted!!!!!!! tempted to just buy one but they are so spendy.

 

[vanlab]

Good post, I have a can coming for my ruger bolt gun, the lack of off the shelf subs available I'll end up loading rolling my own it looks

 

[Grendelhunter]

Good post, I have a can coming for my ruger bolt gun, the lack of off the shelf subs available I'll end up loading rolling my own it looks

Look for these

 

[Grendelhunter]

ive found sub loads available, i just like doing stuff the hard way.

 

[vanlab]

Look for theseView attachment 1206148

Where'd u get those? That must be 2019 prices