9x39 project

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John A.
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Re: 9x39 project

Post by John A. » Fri Oct 11, 2019 6:50 am

Thanks for that info yondering.

I don't have any, but am not against buying a pound of it to try the next time that I order any hazmat stuff.

I'm almost out of titegroup anyway. But I can't complain. I've had that little bottle of powder for a while now and used it for a lot of stuff.
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Re: 9x39 project

Post by John A. » Fri Oct 11, 2019 11:43 am

Well, some more good news with this project.

Lehigh Defense is sending me some of the 254gr expanding pills to test. I know how good they were in my blackout, I expect these are going to be just as good.

I should have them early next week and be able to test them out in some 5 gallon water jugs. That's going to be fun. 8)

I have also figured out how I can use an old school freefloat forend and one of Superlative Arms pistons to make an integral suppressor similar to how I did my integral 9mm upper.

Only reason why I prefer to use a piston over DI is that it would vent and be captured inside of the handguard rather than in the receiver and exiting the ejection port. That would make it more inline with how the vintorez is made anyway.

That's at least what I have in mind at the moment if I build up a semiauto with an integral can. I would like to use a 1.75" ID railed handguard, but I'd have to use an internal tube underneath of it so it would be a sealed system and with a piston, I'm just not sure if there is enough clearance for that.
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x39aesthetics
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Re: 9x39 project

Post by x39aesthetics » Fri Oct 11, 2019 7:24 pm

Hmm, so of something like these? https://m.youtube.com/watch?v=nOqNB4gSJqY
Any idea where to find those for D cell tubes?

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Re: 9x39 project

Post by John A. » Fri Oct 11, 2019 8:27 pm

No, I'm not really sure where you'd find them. I think Rusty said he was retiring.
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x39aesthetics
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Re: 9x39 project

Post by x39aesthetics » Thu Oct 17, 2019 12:58 pm

So here's what I've mocked up. I eyeballed the size of things and it's mostly close, lengthwise.
Image

I did a bunch of research and came to the conclusion that the most effective design depends on a lot of factors, but I've got a couple questions.
1. Is the blast chamber too big?
2. What do I do with the third cone? Stainless or Titanium?
3. Do I get rid of the spacer at the exit port?
4. Is 7 baffles too much in such a small suppressor

I might just make my own thread about it here.

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Re: 9x39 project

Post by #40Fan » Thu Oct 17, 2019 6:25 pm

I would think that 1.48" of blast chamber is too much. Looks like you are going direct thread, so why not tighten it up a bit.

With the Aegis cones, if you'd use a .750" spacer for the BC, and .500" for the rest and fill up the rear with more Ti cones or even aluminum, I think you'd be better off. You'll likely need a spacer at the rear of the can to keep the cone out of the threads.

If I did my math right, you could fit 10 cones, .750" BC, .500" spacers for the rest and a .100" spacer between the last cone and endcap. Might try and find an .125" spacer to allow things to settle a bit. Trim the last .500" after putting a 100 rounds or so through it.

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John A.
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Re: 9x39 project

Post by John A. » Sun Oct 20, 2019 4:34 pm

#40 fan is correct.

The 9x39, being a low pressure round, needs to be treated like a 22 rimfire. Short, almost non-existant expansion chamber, and stuff a ton of baffles in there.
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Re: 9x39 project

Post by John A. » Mon Oct 21, 2019 8:46 pm

Had some time to test out some of the Lehigh bullet hand loads. Man, these things are awesome. I truly believe the 9x39 is about the closest thing to a "wonder round" where subsonics are concerned as I have ever seen.

The 262 gr xtreme defense bullets penetrated through two 5 gallon buckets full of water laid end to end (24 inch penetration) and exited out of the bottom of the bucket and was not recovered. This at 50 yards, from an 790 fps muzzle velocity, so it's performing great even at much lower than normal velocities.

The 254 gr maximum expansion bullets was caught in the 2nd bucket with greater than 14 inches penetration at 50 yards

Full weight retention too.

The 262 gr xtreme defense penetrators and the speer soft points, exited both 5 gallon buckets and were not recovered.
Last edited by John A. on Wed Oct 30, 2019 10:34 pm, edited 1 time in total.
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Re: 9x39 project

Post by John A. » Wed Oct 30, 2019 8:05 pm

All my loads are worked up. Hoping to be able to cross paths with a deer in a few weeks with it.

After season, I intend to shorten the gas block from the pistol length port placement, back an inch and a half further closer to the chamber for a micro gas port placement.

That is similar to what the Russians did with the Vintorez and what piedmont is doing on their barrels.

I'm having so much fun with this upper that I am 99% sure that I'm going to build an integral for it, and port the barrel. I also have a couple of ideas in mind for the suppressor part of the project too. But still am not sure exactly how I want to do the baffles yet. I have a couple of ideas, but nothing in stone.

Anyway, here's a few pictures of the barrel after I turned it down more to move the gas port so I can use the faster burning powders better.

Image

Image

I profiled the area underneath of the gas block a little larger diameter than is supposed to be. If anything, it will give it a little better gas seal I guess.

Image

You can see the new gas port location is dimpled where it'll go, but I'm not going to change anything until after deer season is over, or earlier if we put one in the freezer.

Image

I have several wire gauge bits on order from brownells because I'm not really certain what diameter it'll need to be, but I'm going to start with .090 and move up .005" at a time until I'm happy with it or I get to .125" whichever comes first because .125 is the inside diameter of the gas tube and would have no benefit to drill a port larger than it is.

I'm guessing probably about .105 or maybe .110" will probably be about where it ends up, but I don't know until after drilling and putting a few rounds through it.
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3strucking
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Re: 9x39 project

Post by 3strucking » Wed Oct 30, 2019 8:51 pm

Please dont take my comment as me being a ass but why would you use a subsonic round to try and take a deer?

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Re: 9x39 project

Post by John A. » Wed Oct 30, 2019 10:08 pm

And my reply is not meant to be smart aleck either so don't take it that way.

Because I can. They're not wearing armor.

My shots are always well within 75 yards. And more typically between 7-40 yards.

Further, if you have seen how well the 9x39 was doing with penetration into the 5 gallon water buckets (longways with the buckets laying down on their side with over 28 inches of penetration and not being recovered) at 50 yards and knew that I have tested an all copper expanding bullets that expanded more than an inch in diameter even down to 790 fps velocities, I have no reservations of using a sub on a whitetail.

As far as the bullet weight and velocity, they're delivering more than 600 ft lbs of energy into the target.

That's more than a 357 magnum or even a 44 S&W. Both of which take a lot of deer in my area every year.
Last edited by John A. on Wed Oct 30, 2019 10:16 pm, edited 1 time in total.
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Re: 9x39 project

Post by yondering » Wed Oct 30, 2019 10:14 pm

Because we can, and it works well when done correctly. The 35/9mm bore sizes are easy to make good hollow points expand, and the terminal effects can be excellent so it's not stunt shooting or inhumane.
This is a lot different than guys trying to shoot deer with subsonic 240gr SMK bullets in a 300 Blackout.

Deer and other big game were killed with subsonic bullets for many many years before high velocity rifles came into existence. We have access to even better bullets these days.

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Re: 9x39 project

Post by John A. » Wed Oct 30, 2019 10:23 pm

yondering wrote:
Wed Oct 30, 2019 10:14 pm
Because we can, and it works well when done correctly. The 35/9mm bore sizes are easy to make good hollow points expand, and the terminal effects can be excellent so it's not stunt shooting or inhumane.
This is a lot different than guys trying to shoot deer with subsonic 240gr SMK bullets in a 300 Blackout.

Deer and other big game were killed with subsonic bullets for many many years before high velocity rifles came into existence. We have access to even better bullets these days.
Speaking of better bullets these days.

Here is 254 gr of smack down. This is the one that I recovered in the 2nd bucket meaning that it had at least somewhere between 16-27 inches of penetration. Muzzle velocity of this bullet was 790 fps. 50 yards later it completely passed through one 5 gallon bucket of water and was recovered in the 2nd.

I now have the velocity at 1039 fps at the muzzle for hunting. But during my testing, I was trying to find the floor of how low velocity it would expand and it would down lower than I was willing to shoot anymore.

PS. It is sitting on top of a quarter for reference.

Image
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Re: 9x39 project

Post by John A. » Fri Nov 01, 2019 8:38 am

I just wanted to share this story from a guy I know on another forum. I have seen the photo but since it's not my photo, I'm not going to spread it around everywhere. But here is his story if anyone is concerned about the 9x39 while hunting.
It was a one shot kill at about 65 yards with Tula. She flinched at the shot, went down, got up and just as I was about to hit her again, went down for keeps.
I got full (through) penetration on the elk. She was broadside. I double lunged her and ironically, the bullet broke no rib bones, but rather slipped between them on both sides. She was in the brush, it was a difficult shot and the only one I had. I was not happy about using FMJ but it was all I had at the time and since I am a lifelong handgun hunter, I knew it should work if shot placement was good. It was my first elk.
It wasn't the biggest cow elk that I have ever seen, but it certainly was a mature one.
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Re: 9x39 project

Post by x39aesthetics » Fri Nov 01, 2019 4:24 pm

I imagine it would make a good hog cartridge if you're into that kind of stuff

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Re: 9x39 project

Post by John A. » Sun Nov 03, 2019 3:55 pm

I've been thinking hard about ways to keep FRP down on the 9x39. Even with a super short expansion chamber in my 9mm can that I am using on it, there is a lot of noise with the first few shots.

With not really wanting to use copper chore boy wrap, or fiberglass muffler packing which blows out in a few shots, or even those magic erasers that disintegrate rather quickly, or even liquid ablative, what do you guys suggest? Thinking that maybe a wipe would be a good idea. Except for when using those expanding bullets. That would probably be a disaster waiting to happen. But for most any other type of bullet may work OK>

But curious what you guys may suggest ???

I have an idea for a couple of diffuser chambers prior to baffles and actual expansion chamber.
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Re: 9x39 project

Post by a_canadian » Sun Nov 03, 2019 5:56 pm

A syringe with white lithium grease to top up the first baffle or two every couple of dozen shots. A modest coating of the grease on the faces of the first two baffles whenever you rebuild the stack at cleaning time. Works for me, if only in subsonic .22lr.

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Re: 9x39 project

Post by yondering » Mon Nov 04, 2019 1:24 am

John A. wrote:
Sun Nov 03, 2019 3:55 pm
I've been thinking hard about ways to keep FRP down on the 9x39. Even with a super short expansion chamber in my 9mm can that I am using on it, there is a lot of noise with the first few shots.

With not really wanting to use copper chore boy wrap, or fiberglass muffler packing which blows out in a few shots, or even those magic erasers that disintegrate rather quickly, or even liquid ablative, what do you guys suggest? Thinking that maybe a wipe would be a good idea. Except for when using those expanding bullets. That would probably be a disaster waiting to happen. But for most any other type of bullet may work OK>

But curious what you guys may suggest ???

I have an idea for a couple of diffuser chambers prior to baffles and actual expansion chamber.
I've been using a grease called Sil-Glide, available from Napa Auto Parts. It stays in the can for months without drying up, and the effect is similar to vaseline. I'm not getting any noticeable FRP with my 358 Herrett with either my Mystic X or my 35 cal F1 rifle can (although I don't normally use ablative in the rifle can).

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Re: 9x39 project

Post by John A. » Mon Nov 04, 2019 8:19 am

I've never heard of that. Thanks Yondering.

I have used lithium grease before. I found it to be super smokey and that stuff probably isn't all that great to breathe in its' vaporized form either.
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Re: 9x39 project

Post by #40Fan » Tue Nov 05, 2019 12:13 am

Would more cones filling up volume be the better route to go?

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Re: 9x39 project

Post by yondering » Tue Nov 05, 2019 3:11 am

John A. wrote:
Mon Nov 04, 2019 8:19 am
I've never heard of that. Thanks Yondering.

I have used lithium grease before. I found it to be super smokey and that stuff probably isn't all that great to breathe in its' vaporized form either.
Sil-Glide is smoky too, like vaseline, but not as bad as lithium and the smell is not objectionable (IMO). It reminds me of grilling meat a little bit. The main reason I use it is that is stays put and also works well to lube my 9mm booster.

I built my first rifle F1 (~10 years ago IIRC) can in such a way that I could re-arrange the cones and spacers to experiment with FRP and tone. Same number of cones in each configuration, just different placement of the spacers. This is with simple clipped cones, but I made them very thin to occupy as little volume as possible. As expected, a large blast chamber gave more FRP with the subsonic rifle stuff but the best sound on subsequent shots (I was experimenting a lot with subsonic 35 Remington and ~270gr bullets at the time, so I think it's relevant to the 9x39). A smaller blast chamber and more even baffle spacing pretty much eliminated FRP but had a somewhat higher pitched tone.
I settled on a progressive baffle spacing where the cones nearest the blast chamber were ~.75" apart and progressively stacking closer down the tube, with the closest at ~.3" near the suppressor exit. I left one large gap before the exit since that seemed to improve the tone. That configuration is what I still use now, and was my best compromise between FRP and tone while still accommodating full power 308 as well. It has minimal FRP with subsonics, and with full power rifle loads (223, 6.5 Creed, 308 etc) I don't notice any FRP at all.

If it were a subsonic-only can I'd probably add one more baffle in the blast chamber area but keep the progressive spacing.

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Re: 9x39 project

Post by John A. » Tue Nov 05, 2019 7:57 am

Very good information and mirrors a lot of what I have seen through my limited experiments by rearranging spacers too.

I think I have came up with an idea to reduce FRP by making 2 diffuser baffles or chambers prior to actually reaching the expansion chamber in the can.

They will be similar to those compensators that have a ton of tiny holes in them. While it will also have a much smaller inside diameter of those than a hollow empty expansion chamber would.

It would basically work on the same principle as ported barrels over the barrel, but obviously inside of the suppressor tube. I'm thinking with the smaller ID, should have less oxygen to burn initially than a large open spacer and chamber. And thus making it more quiet.

I hope.

The ID of the first one straight out of the barrel would be ~ 9/16 since that would be about the diameter of the 5/8-24 threading. The next diffuser chamber would be ~.500" most of the way through it, but there would be an internal lip just prior to exiting out into the expansion chamber the actual bore diameter of around .406", which would make it sort of a ledge or speed bump that would block and slow some of the expanding gas which I think would cause it to build slightly more pressure internally and port a little more into the suppressor tube due to varying internal pressures due to the different sizes.

Kind of hard to explain in words what I have in mind. But I think will reduce FRP substantially. Less space, more turbulence. I want to at least try it.
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Re: 9x39 project

Post by John A. » Thu Nov 14, 2019 12:24 pm

I drilled 20 of the 30 port holes that I have dimpled in the barrel. I'm more concerned about having adequate gas to cycle than porting gas out of the barrel at this moment and I can always port more holes later if I want or need to. But basing this on the Russian design that used 54 ports, and with the placement of everything being near the same, should give me enough pressure to be alright. Worse case scenario, I can always plug tap some of the ports to block them off if I make too many, but it's a lot more simple for me to stop where I am right now and get full function first and foremost.

I plan to load up some test rounds to work up the gas port size as early as this weekend. Since it's cold out, I'm going to set up my video camera to take a few videos of the side of the ejection port side of the gun for a couple of reasons. Mainly so I can review it to help me make my decisions about ejection and should also have an easy time detecting the hot ported gas over the barrel to see how all of that is doing.

You'll see the original gas port in the barrel just forward of the gas block in the picture below. I have already threaded a portion of the top of the hole so I can plug that up because I want to give the new gas block all the gas pressure there. I didn't thread the entire hole for a couple of reasons. Mainly so there would be no possibility for vibration to allow the bolt to protrude down into the barrel and obstruct the bore. And secondly, so the gas port diameter in the barrel isn't enlarged in the remote chance that I move the gas block back to there.

Image
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Re: 9x39 project

Post by garredondojr » Thu Nov 14, 2019 9:55 pm

Sounds like your all in on this one! lol

Did you submit a new form 1 already?

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Re: 9x39 project

Post by John A. » Thu Nov 14, 2019 10:05 pm

Not yet. It's on my to do list and probably tomorrow or maybe Saturday. I just have to try to figure the e-file thing out.

Last time didn't really go so well and I got locked out, but that was with my old computer. I have replaced it since then so I'm hoping that it works out a little better this time. :roll:
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