9x39 project

[John A.]

Guys, I'm seriously considering a 9x39 project. And in my typical fashion, will be quite unorthodox.

My main question is, what would be the best type of baffle to use?

I'm hesitant with cones because I have never really heard a very good cone baffle with subsonic stuff. And monocores still seem to leave a lot to be desired too. Except for rimfire.

My plan is to build an integral can. In total about 16.5" long which will be housed entirely underneath of the handguard (the mlok handguard will be the outer body of the suppressor.

Will have a ported barrel. Possibly some reflex ports at the muzzle.

And it will not be on a semiauto either, which will eliminate ejection port noise, gassing and fouling. Basically, I plan to make it a bolt action side charged upper. And will also open up me being able to use a lot more powders that would not ordinarily cycle the bolt.

I will be working with my buddy on his quickload program to use fast burning powders that will burn out and achieve the full (desired) velocity before leaving the barrel. He has already shown me a potential load with about 7 grains of universal powder that I may try. That's a lot faster burn rate than the enforcer that I'm using on the blackout. And that's also with a 300 grain bullet too.

So, this is going to be a multifaceted approach to make the most quiet integrally suppressed upper that I can.

But, I don't have an idea of how to make the baffles. Whatever it is, would seem to be better than the bent and welded steel that the Russians use.


image from: http://www.sadefensejournal.com/wp/the- ... per-rifle/

[Historian]

Dan Shea & Dr. Philip H. Dater's article has a good write up on the 9x39. Ammo
commands an eye opening price.

<< http://www.smallarmsreview.com/display. ... icles=1105 >>


As for the can, it uses the 'tried and true' , typically Russian peasant no frills design yet simple
and effective Stetchkin can. On the APB (Avtomaticheskiy Pistolet Stechkina) there are
postings of the can's effectiveness in semi and full auto.

For collectors information there are 3 excellent versions of the Stetchkin shoulder stock holster:
the Wood Holster in the vein of the C96 Mauser Broomhandle, a wire that is part of
the silencer, and the rugged Bakelite heavy duty.

<< https://enemymilitaria.com/product/sovi ... ter-strap/ >>
<< https://www.ebay.com/itm/ORIGINAL-RUSSI ... 3289631353 >>

[John A.]

Thank you for the reply historian. It is appreciated. I was able to learn about the Stetchkin pistol this morning. One that I knew nothing about until today.

Yes, the silencer baffle is typical no frills baffle. I strongly believe that I can do better.

And since I'm not worrying about semi/fa and cycling the bolt by hand, that will open up a lot more options for better powders too. So, I have no doubt that I will be able to surpass what the Russians have done.

I just have to figure out which baffle type would work best.

Omega baffles and K baffles have always worked well in 9mm (caliber and pressure) guns. The RSC style baffle works well in 9mm too. I've never heard a radial style baffle in person. So, I'm torn at which baffle to use.

Do you have any suggestions?

[fishman]

IMO, the entire point of 9x39 is if you want a quiet AK-ish gun. For an AR or a bolt gun, why not just use 300blk, 338 whisper, 350 legend, 458 socom, 510 whisper?

An integral VSS or AK in 9x39 would be cool because they're iconic. A bolt gun in 9x39, not so much.

K baffles kick ass for 9mm and 300blk. I bet they would for 9x39 as well.

[John A.]

I already have an integrally suppressed 300 blk.

The whole point to me is to make the most quiet 9x39 in existence. I think I can do better than the Russians. It's really nothing more simple than that.

With not only the way that I make the gun, but the bullets too.

[Historian]

I already have an integrally suppressed 300 blk.

The whole point to me is to make the most quiet 9x39 in existence. I think I can do better than the Russians. It's really nothing more simple than that.

With not only the way that I make the gun, but the bullets too.

Bravo!

It has been a long time since an interesting action item has been offered. In this vein
I shall review some long ago designs that might be added to your thoughts. It is
coincidental that I am starting to clean out a dust covered filing cabinet drawer of long lost
sketches and designs of nonconventional cans, accumulated over 50 years. Many culled
from foreign sources, articles, and discussions with a creative Gyrene Major. RIP, Dick.

[John A.]

Thank you.

I always look forward to hearing anything that you can share. I enjoy learning and seeing stuff that I probably would never see otherwise.

Thanks buddy, you're welcome to PM or email, or call any time.

[garredondojr]

Sounds like one of my crazy projects lol. I however pan to do the vintorez'esq build on the AR platform with a ~9" barrel and an pinnned/welded faux suppressor tube with some nagant iron sights welded onto it that will be large enough ID for my 9mm form 1 to fit into.

I made myself a "cherry" and cut a mold for a monster semi high bc cast bullet. it ended up dropping at 354gr naked and I intend on powdercoating them.

Have 2 other projects in front of this one. however so i've put it on the back burner.

Mine is patterned off the 6.8 spc case (however i'm using 22 nosler brass so I can be cheap and use a .223 bolt) I use 357 herrett dies shortened .100" so no custom dies needed. then shorten the neck .050 from the standard .357 herrett so -.150" total.

Haven't decided if i'll rent a 357 herrett reamer and chamber .100" short and deal with the excessive freebore from the .050" of unused neck or pony up and buy a reamer.

This allows me usage of 9mm, 38/357 and 35 caliber rifle bullets as opposed to the oddball .362 or what ever it is of the 9x39. same goes for easy to find and cheap blanks. GM rifle barrel 9mm blanks are .357 groove and the smaller bore for 9mm so a win win and did I mention their cheap! lol

Oh yeah picture dir!

[John A.]

Sounds like you've got a really neat project in the works too.

I'm still waiting on delta team tactical/Davidson Defense to ship the barrel and the bolt. I'm not sure how much longer that is going to take but it's all that I'm waiting on to move forward.

I have made the new bolt handle. Threaded the bolt carrier for it. And milled and cleaned up the slot for it.

Started off with a pilot hole in the receiver which let me dimple mark the carrier where the bolt handle was going to go.



Marked everything with a framing square so I know everything was straight. Also applied masking tape to the receiver to prevent any big scuffs while I was working on it. And as a cheater mark so I know where to stop milling. I made sure I had enough movement rearward to lock the bolt open on an empty mag.



Then the fun part.

Slinging chips on my homemade milling table.



A quick picture before I clean off the burrs and paint the raw material.



The bolt handle clears the BHO lever.


And locks open on an empty mag.


I went back and forth deciding whether or not I wanted to use a factory charging handle. After some careful thought, I did for a few reasons. First off, it would help keep the carrier aligned better in the receiver due to the gas key riding in it. While this is no different than while in the gas operated AR, it's the main reason that I wanted to use it. Plus, the front of the charging handle relieves the bolt from striking the barrel extension as hard too and acts sort of like a mechanical buffer or stop so the two don't batter each other as much.

But I didn't want the big ears sticking out as much so I removed much of the material to give it a lower profile.


Unfortunately though, I removed a little too much material on the right side and exposed the charging handle spring slot so I had to thread and install a short bolt to retain the spring. I trimmed the spring flush with the outside of the charging handle but once I screwed the bolt in the hole, it increased the spring tension on the little lock. Which worked out better anyway. While accidental, I'm glad that it happened. Though I do hate that there is an unsightly button there now.

I considered drilling a small pin hole and placing a pin through the end of the channel to retain the spring and then JB weld over it which would have been just as functional, but the screw stop works.



Still I don't think the bolt detracts too much from the project though
[imghttps://i.imgur.com/8qtSyK4.jpg?1][/img]

[garredondojr]

Looking good!

LIke what you did on the charging handle. I may have to steal that idea Another one of my project plans it to make a manual action upper like your doing and cutting the BCG just past the firing pin so I can put a true folding stock on it (no protrusion past the receiver) thus making a Q "the fix" type rifle except straight pull bolt.

[John A.]

Thanks.

I can't take full credit for the overall design though.

The basic principle has been in effect for many years now in England.

https://www.youtube.com/watch?v=gS6fGmYl-fM

As for cutting off a bolt carrier so you can add a folding stock, there is a guy on youtube doing something similar. Only he is not adding a stock at all.

He calls it the Han Solo Blackout or something of the sorts.

I'm looking into a way to follow in the vein of the original Delisle and add a rubber grommet so it will buffer some of the action noise around the bolt handle. As I think I mentioned earlier, my intention is to make a quieter 9x39. And that is just another thing that I am thinking of trying to address some of the noise.

[garredondojr]

Thanks.

I can't take full credit for the overall design though.

The basic principle has been in effect for many years now in England.

https://www.youtube.com/watch?v=gS6fGmYl-fM

As for cutting off a bolt carrier so you can add a folding stock, there is a guy on youtube doing something similar. Only he is not adding a stock at all.

He calls it the Han Solo Blackout or something of the sorts.

I'm looking into a way to follow in the vein of the original Delisle and add a rubber grommet so it will buffer some of the action noise around the bolt handle. As I think I mentioned earlier, my intention is to make a quieter 9x39. And that is just another thing that I am thinking of trying to address some of the noise.

Yeah I remember hearing about the Lantac UK straight pull AR's years ago. I want to say POF has something similar in a large frame (.308 pattern) but yes all the same fundamentals.

The "Solo 300" pistol is where I got the cut carrier idea from as well. He actually used polymer receivers which should dampen some of the noise too I assume. I planned on making a derlin/nylon bumper at the rear of the carrier travel to act as a noise dampened positive stop and a bushing of a similar material on the shank of the handle that would ride the milled slot in the receiver and act as a stop for going into battery.

I played with the idea of a toggle action as well,(like the olympic 22lr's) but i'm not sure there would be sufficient extraction leverage to cycle the action.

But for sure building something like the Mini Fix on the ar platform definitely sounds fun for sure.


I thought about using the cherry I made for the 354gr bullet to cut a mold thats shorter maybe weighing 200-250gr stuffed in a 9mm case then make a barrel with a generous throat would make for a fun plinker. I also have a 200gr rnfp mold that would be a turn key solution with an opened up throat.

Figured you may get a kick out of this.

[John A.]

Lots of good ideas floating around.

I've seen a few guys with some load data using 6.5 Grendel starline brass and 9.3mm mauser bullets.

[garredondojr]

Lots of good ideas floating around.

I've seen a few guys with some load data using 6.5 Grendel starline brass and 9.3mm mauser bullets.

I think starline makes Grendel "basic" brass (straight walled) if that would be any better for forming 9x39 brass?

[John A.]

Finally got the barrel yesterday and was able to put a few rounds downrange using one of my 9mm F1's and wanted to share a few observations with you guys.

I know that many people are comparing this cartridge as the "Russian equivelant to the Blk". I would say there are some similarities, but that's where they stop.

I noticed that the gas port on the KAK barrel was at pistol length placement. Piedmont is doing a "shorter than pistol length" placement on their barrels which would cycle lower pressure loads easier.

FWIW, the 9x39 gas port diameter was .122" the best that I could get without using a pin gauge so I'm going to say the gas port is the same as my blk.

Also, I could not get more than 5 rounds in a mag without having to beat the mag into the lower due to swelling out the mag body. I was using ASC brand 7.62x39 magazines. I'm going to try Cproducts next to see if they do any better since they use 400 grade stainless steel bodies on their mags. Though I don't pretend that will fix it altogether.

For my purpose, I would be fine with a single stack 10 rounder. But is getting off subject.

Straight out of the gate with no tinkering, the 9x39 was more quiet than the blackout subsonics with factory ammo. I haven't even tweaked the gun or the loads yet. So, I have high hopes that I will be able to get it way more quieter once I port the barrel like the Russians and I use fast burning powders since I won't have to worry about choosing a powder with enough excess gas to cycle the bolt since I've built a straight pull bolt action.

Since I went shooting with it yesterday evening, I have removed the rubber extractor buffer because it made it much harder to close the bolt and is unnecessary. And I'm going to chamfer the outside edge of the slot that I milled because I drew blood twice from rubbing my thumb and my pointer finger knuckle across it.

Anyway, I think this is going to be a fun project gun. And I think it's going to turn out to be a fun one once I finish with it.

The camera is about 3 1/2 feet from the side of the muzzle. You'll hear me insert the mag, chamber a round and the loud pop is the extractor going over the rim of the case. It's considerably better now that I removed the rubber buffer. Then obviously you'll hear me fire it.

(told you that it was more quiet than the blackout straight out of the gate)

https://www.youtube.com/watch?v=asCOtlwmoWE

[yondering]

Also, I could not get more than 5 rounds in a mag without having to beat the mag into the lower due to swelling out the mag body. I was using ASC brand 7.62x39 magazines. I'm going to try Cproducts next to see if they do any better since they use 400 grade stainless steel bodies on their mags. Though I don't pretend that will fix it altogether.

You'll need to cut the rib out of the magazine on each side, see pic below. Otherwise the fatter 35 cal bullets cause the rounds to pidgeon toe in the mag and bulge out the sides. Also, are you using the stainless ASC mags, or the aluminum version? The stainless is the way to go; they work well for me in 6.8 and Grendel flavors for various wildcats.

This pic below is my 358 Herrett, which I've posted about on the NFAtalk forum. It's a pretty similar idea to what you're doing, just easier to implement. 200gr FTX bullets in the rounds shown in the pic, but I also use a 255gr hollow point and 270gr solids for subsonics.



Also I like your side charge handle above. I've done a few that way myself, like this one below. That is a titanium handle with a socket head cap screw through the center. I made my first few handles from O1 tool steel with integral threads and heat treated them, but drilling through and using a SHCS is easier and stronger.
I use the side charge handle like this for subsonics in several AR calibers. Mostly I leave the gas system functional and just load really quiet rounds with fast pistol powder (Clays, Red Dot, Bullseye, etc); those don't cycle the action and end up being about the same noise level to bystanders and the shooter as when the gas is blocked off.



One revision I made on charge handles though happened after I threw one of these rifles over my head on a sling - the side charge handle dug into my kindney pretty hard. I came up with this low profile version that I use instead now; it doesn't have quite as much leverage but still works well and stays out of the way. It is more robust too, as a side benefit.

[yondering]

Sounds like one of my crazy projects lol. I however pan to do the vintorez'esq build on the AR platform with a ~9" barrel and an pinnned/welded faux suppressor tube with some nagant iron sights welded onto it that will be large enough ID for my 9mm form 1 to fit into.

I made myself a "cherry" and cut a mold for a monster semi high bc cast bullet. it ended up dropping at 354gr naked and I intend on powdercoating them.

Have 2 other projects in front of this one. however so i've put it on the back burner.

Mine is patterned off the 6.8 spc case (however i'm using 22 nosler brass so I can be cheap and use a .223 bolt) I use 357 herrett dies shortened .100" so no custom dies needed. then shorten the neck .050 from the standard .357 herrett so -.150" total.

Haven't decided if i'll rent a 357 herrett reamer and chamber .100" short and deal with the excessive freebore from the .050" of unused neck or pony up and buy a reamer.

This allows me usage of 9mm, 38/357 and 35 caliber rifle bullets as opposed to the oddball .362 or what ever it is of the 9x39. same goes for easy to find and cheap blanks. GM rifle barrel 9mm blanks are .357 groove and the smaller bore for 9mm so a win win and did I mention their cheap! lol

Oh yeah picture dir!

Sounds a lot like my 358 Herrett, same idea. I used Green Mountain blanks too, but in .358" diameter because I wanted the faster 1:14 twist and planned to use .358 rifle bullets anyway. (IIRC when I did mine the .357" were only in 1:20 twist or slower.) I built mine mostly to duplicate 20" 35 Remington in a 16" AR, and it does that well, but the heavy bullets subsonic are fun too. How well does that heavy 354gr bullet stabilize from yours?

22 Nosler didn't exist when I built mine, so I used 6.8 bolts, but that's a good idea.

The freebore in this one is a non-issue, and allows higher velocity for full power loads anyway. My 16" version still prints the 200gr FTX into little bitty groups at 100 yards, more than good enough for hunting.

[3strucking]

Did the 9x39 round go supersonic? I hear a crack in your video. Maybe it’s just me. I have wanted a 9x39 but I have not committed just yet.

[John A.]

Yondering, you've done nice work on making that.

I didn't cut the rib in my mag. I did use SS mags though.

In knowing that the 9x39 is based on the 7.62x39 case, I tried using a 7.62x39 magazine, but the follower was all the wrong geometry.

I took the follower out and just sat 2 rounds on top of each other and you could easily see that nearly 1/4 of the brass case stuck over past the edge of the follower, which would've been exerting pressure onto the mag body causing it to swell.



So, I ended up filing some of the ledge off of the follower so the bottom cartridge would sit closer to the center of the magazine and when I did that, it raised cartridge 2 slightly off of the top of the follower, so I used JB weld on top of the ledge so there would be no gap and would support the other cases once it was loaded.



After I did that, I was able to load 18 rounds into the 20 round magazine. I didn't expect to load all 20 rounds the 7.62x39 mag was rated at because I knew the 9.3mm bullet took up more space and lower the capacity somewhat so it wasn't a surprise that it didn't hold 20 rounds when I finished.

But, after the follower mod, I was able to have a fully functional mag that would hold more than 4 or 5 bullets. Though after 11 rounds it wouldn't drop free, but did insert and remove very easily with only 2 finger pressure pinching on it. I still consider that a win.

D&H is in the process of prototyping a 9x39 mag. When I was speaking with their designing engineer he said that he expected that it would be released at SHOT.

3Strucking, no the 9x39 didn't go super. I only shot a half a box so far because I was just wanting to put a few rounds through it to get a baseline of how it worked so I can compare to before/after. I intend to shoot some over a chrony fairly soon because I am going to be porting the barrel and I want to keep the velocity up as much as I can, but port out some of the unnecessary gas over the barrel too.

I'll be doing some load testing using some fast burning powders so the pressure builds up quickly but should mostly burn out in the first 7 or 8 inches of barrel so it should be even more quiet by the time that I finish the project.

[3strucking]

Keep us posted. I wonder if mcgowen offers a remage barrel in 9x39?

[3strucking]

Yondering, Whats the heaviest off the shelf bullet?

[John A.]

Keep us posted. I wonder if mcgowen offers a remage barrel in 9x39?

KAK has them.

https://www.kakindustry.com/kak-rem-700 ... ile-barrel

[garredondojr]

Sounds a lot like my 358 Herrett, same idea. I used Green Mountain blanks too, but in .358" diameter because I wanted the faster 1:14 twist and planned to use .358 rifle bullets anyway. (IIRC when I did mine the .357" were only in 1:20 twist or slower.) I built mine mostly to duplicate 20" 35 Remington in a 16" AR, and it does that well, but the heavy bullets subsonic are fun too. How well does that heavy 354gr bullet stabilize from yours?

22 Nosler didn't exist when I built mine, so I used 6.8 bolts, but that's a good idea.

The freebore in this one is a non-issue, and allows higher velocity for full power loads anyway. My 16" version still prints the 200gr FTX into little bitty groups at 100 yards, more than good enough for hunting.

I haven't chambered a barrel yet. I have a few other wildcats i've been working on in front of this project. Everything thus far has been more of a proof of concept than anything. ie. stepping stones, designed bullet, made cutter, cut mold, poured bullets, bought dies and brass, shortened dies, necked up and sized cases, ordered blank. thats where i'm at currently. Like I mentioned above i'm not sure i'll buy a custom reamer or just use a 357 herrett reamer and chamber .150" short. I have considered making my own from O1 but haven't tried yet.

My blank is a 1:10 twist which should have no problem spinning up that 354gr bullet.

John looking good and nice work around on the mags.

[yondering]

I didn't cut the rib in my mag. I did use SS mags though.

I think regardless of the follower work, you'll have to remove the ribs to get them to work right. If you don't have a mill, just cover shipping and I'll do it for you on a mag or two, it's pretty quick and easy and I don't mind contributing to a cool project.

garredondojr - I rented a 357 Herrett reamer from 4D Reamer Rentals, and am very satisfied with the results. It worked well enough that I did it again for another set of barrels (I've made 4 of these, two 10.5" and two 16"); the chamber turned out exactly how I wanted and all of the barrels are more accurate than I expected.

3strucking - for .358" rifle bullets the heaviest mainstream common jacketed bullets are 250gr, but I think there are some 300gr available from one or two smaller makers. I forget the names though, since this is a perfect application for heavy cast bullets. I don't know of a source for heavy cast bullets though since I cast my own and don't need to buy them.

BTW - regardless if it's a .358" or .362" bore, the 35 caliber works a LOT better for subsonic hollow point cast bullets than 30 cal and smaller. It's a lot easier to include a decent size hollow point in the larger caliber, and that goes a long way to making a subsonic hollow point work.
Here is a pic of my 255gr; I've had really good success with this one on deer. I use it from several different cartridges (35 Whelen, 35 Remington, 358 Herrett, 38 Special/357), generally launched at 1,000 fps. (this pic was intended as an analysis of the bullet coatings, but shows the bullet performance well)

[yondering]

I'll be doing some load testing using some fast burning powders so the pressure builds up quickly but should mostly burn out in the first 7 or 8 inches of barrel so it should be even more quiet by the time that I finish the project.

Your 9x39 is different than the 358 Herrett of course, but I think the case capacity is similar enough that this might be useful:
My preferred subsonic powder for that 255gr bullet is SR7625, but it's been discontinued. If you don't have any, I also had good results with Green Dot and Longshot. (part of the selection process was finding powders that sound good suppressed) These were chosen partly based on cycling a 10.5" AR with a .125" gas port (pistol gas), so faster powders may work well too if that's not a criteria.

All of these give right about 1,000 fps (give or take 20 fps) with that 255gr bullet from a 10.5" barrel:
SR7625 8.3gr
Green Dot 7.4gr
Longshot 7.2gr