View Full Version : MO193 SubSonic round

Medula Oblongata
11-13-2005, 08:51 PM
Well, I decided to start a new thread on the SubSonic loads, as the last one is too long and full of discussions not relating to reloading.

Here are my newest test results (still no chrono though :():

3.3grns Viht 3N37
1.128" 1x fired case
55grn Winchester FMJBT
1.580 seating depth
Remington 7 1/2 BR primers

IT WORKS, but don't know if truly "subsonic." With this powder and load I was able to reliably (and extremely accurately) fire this round AND THE SLIDE CYCLED EVERY TIME. For the sake of safety, please decrease by 10% and work up to 3.3. I arrived at the 3.3 grain starting point with this powder though mathmatical calculations of case capacity, approximate burning rate, projectile depth, projectile weight, barrel length, and a little bit of "black magic."

I had an assortment of 55grain projectiles loaded all the way from 3.3 to 4, but decided to not even try anything over 3.3 based upon the function of the 3.3 charge. I haven't been near my house recently (so I can't order a chrono and have it delivered, don't know where I will be every day) and every gun shop I have stopped at along the way (including Bass Pro Shops, Springfield MO) does not carry them. So, if anyone is inclined to try this load and chrono it, please post your results.

The accuracy was outstanding (1/2" group @ 21' offhand) and only shot about 2-3" low as compared to my handloaded 40grn Sierra BlitzKing, 40grn Nosler Ballistic tip, and 40grn Hornady VMax. The hole in the target was perfectly concentric and showed no instability of the projectiles direction and attitude, meaning the bullet hole looked just like the ones from all my other rounds (no keyholing). The recoil was not abnormally great, but a little more than SS192. The muzzleblast was quite loud and there was quite a bit of bright flash though, but not much more than the same powder @ 6 grains and a 40grn bullet. The primer showed slight "raised donut cratering", but not severe, perhaps a little less than the 6grns & 40grn Vmax.

I have decided to jokingly name this load after myself :), the MO193. Remember though, that I AM NOT RESPONSIBLE IF YOU BLOW YOUR GUN UP AND LOOSE YOUR HANDS as your reloading procedures are beyond my control. They worked fine in MY gun, but I cannot and will not be responsible for your gun. As with ANY reloading project, start low and work up to maximum. For safety's sake, I will call 3.3 grains 3N37 a "maximum" charge for this projectile.

I have spend many hundreds of hours developing my loads and data, and am quite protective of them. I am sharing them with you guys, slowly, because I am concerned that someone who is not an experienced reloader may hurt themselves. I have been reloading since the 1970's and I consider myself to be an intermediate reloader. Thoughtfully determine your own expertise and experience before exceeding 3.3 grains, and do so at your own risk.

HHI 812
11-14-2005, 06:47 PM
Thanks for the info! Buddy has a bunch of these bullets, and will give it a try. Still can't find any 3N37 at any decent price(only know of one dusty can at a store at $28+). Just tried some IMR 4756 that I had, but didn't get any velocities from my cheap little chrony? Kept getting errors, and could be due to being too close, or too cold. Was like close to single digits, and with the wind, probably was below 0. Took a chance on some charges, that I used from comparing with HS6 and 3N37 in other cartridges, and I think I was pretty close in my estimates. On the warmer charges, I loaded only 1 round of each as I started getting to a warmer load, and noticed slight cratering. Had one misfire for some reason? Looked to be a light primer strike? Other than that, out of the 40 rounds I loaded, the slide ejected everything ok, and a couple loads grouped 5 shots easily under 2" at 20 yards, and often 3 or 4 shots touching. Flyers most probably was me shivering. I was leaning my hands on a shooting table. I'll see how it works with the 55 grainers? Did notice the SS196 shot lower than the SS195LF? Is that how it supposed to be? I thought heavier slower bullets usually go higher? That is how it was with the .44, .45's, .475's and 500's I've shot in the past out of revolvers?

Medula Oblongata
11-15-2005, 12:28 PM
My pesonal experience has always been that heavier bullets with the same powder charge as light bullets do shoot significantly higher (.338 RUM in 250 grain was 14" higher with an identicle powder charge as 185 grain, and 3" in 45ACP with 185 vs. 230) because the bullet stays in the barrel longer at a higher pressure and causes a greater muzzle impulse. With the 196 (and my SS stuff) the powder charge is significantly lower than comparable 40 grain handloads, I can see why it would shoot lower. Just less velocity and a faster drop.

I confirmed my findings this mornig with John Lee of Lee Precision who noted the same findings on heavy vs. light bullets with similiar charges, and the affects of reduced charges on heavier projectiles. We spoke for probably 30 minutes and I think I interested him in the round. He said he would contact me in the near future and let me know if they would produce "custom" die sets, case trimmers, and shell plates. I really like Lee dies and would LOVE to see them in 5.7x28. Now if I can just convince them to make the dies in carbide...

I have some ancient RCBS and Hollywood dies in 30-06 that are true carbide (non-lube) dies and I would orgasm all over myself if they made something similiar in 5.7x28. I HATE CASE LUBE MORE THAN I HATE THE BRADYBUNCH!!!

HHI 812
11-15-2005, 06:49 PM
I called Lee Precision a couple weeks ago, about the case trimmer, dies, and shell plates, and the receptionist said nothing in there line. I asked if they will be doing it soon, and I heard her ask Mr. Lee, and he said no, none of the accessories. I wanted one of their case trimmers in particular, since they have done custom ones for me before, but she said there is no shell holder they have that will fit it, and they will not make any custom case gauges if there is no shell holder. Not wanting to take no for an answer, I called back and told them that they have a universal chuck that would work for a shell holder! She said I was right, and asked one of the techs and he said well then, we "can" make a custom trim gauge! So I spoke to the tech, and he said he recalls only 2 requests for the 5.7 dies in the last 2 years, so doubt they would make dies. I told him about the FiveseveN now available, as well as the PS90 soon, and Fiochi coming out with ammo, and he said well like everything else, if enough requests, they might have to change their mind and make the accessories. To be fair to Mr. Lee, I have to admit he does listen to his users. When the .480 Ruger first came out, I asked for a .475 mold. Tech told me they had a design spec ready to be produced, and it was on Mr. Lee's desk and was already set. When he told me the specs, I knew it wouldn't work in the FA .475, and wasn't a good design for the just introduced longer cylindered .480 Ruger. I called and asked for Mr. Lee, and told him the flaws of his design, and then asked me how I thought it should be? Well, he said he would send my a prototype mold in about a month, and to let him know what I thought? Well, the "next" week, he sent me an unmarked proto mold with some of my suggested improvements! Although not to my exact measurements, it still was better than their original design, and it works in both the FA .475 and uses the .480 Ruger's long cylinder, and listed in their catalog. I guess if enough of us kept bugging them about some dies, trimmers etc, I'm sure they'll break down and make them! Their prices may be cheap, but they do make good dies and trimmers, and has a lot of inovative ideas they've come up with and other big name reloading companies use. Lets just keep calling them up!

Medula Oblongata
11-15-2005, 10:25 PM
Absolutely right, my friend!!!

Lets all keep (or start) calling Lee and DEMAND :) Lee dies, shell plates, and trimmers for the FiveseveN!!!

I will call, from now on, once a week until I get what I want!!!

<<<Baby wants his lolly pop>>>

11-20-2005, 07:27 PM
Hey, do you have chrono numbers?

Also, we want gel or varmint tests. Not much point to sticking faux-M193 into a Five-seveN or PS90 if it doesn't do better damage than the standard loads.

11-21-2005, 02:34 PM
Beggers and choosers. I, for one, am grateful to those that are doing the footwork and contributing their findings rather than just reading about it.

The biggest issue with the SB193 (IMO) is sheer lack of availability on the street. Couple that with functional issues and stability issues, and the MO193 has a lot going for it, even though it's in its infancy and not fully documented (yet.)

Paitience and elbow grease will get you further than...

Medula Oblongata
11-24-2005, 11:53 AM
Hey, do you have chrono numbers?

Also, we want gel or varmint tests. Not much point to sticking faux-M193 into a Five-seveN or PS90 if it doesn't do better damage than the standard loads.

The point of developing this round was not to get "better damage" than the light weight stuff, but to have something to use that is quiet enough to shoot in your basement, supressed or otherwise.

Also, having an assortment of projectiles makes it a more versatile platform, and allows others that would otherwise, due to lack of projectile availability, not be able to reload. The amount of damage from a 55grn projectile at 1000fps would be roughly equivalent to a 35 at 2000fps from sheer energy delivery and crushing force. But my intention was never to create something "better damaging." I was just creating another option. FYI, according to my agency lab manual, the SB193 will penetrate CRISAT armor up to 50m from the P90 and up to 20m from the FiveseveN.

As for gel and varmint tests, feel free to post your results, we all would love to see them.

01-14-2006, 11:58 PM
Has anyone chronoed the MO193 round yet? I am trying to justify to myself the purchase of a gem-tech 5.7 suppressor. :)

01-15-2006, 05:48 AM
I'd be glad to test some rounds but don't have any 3N37 power. I've mostly used HS6 and AA7 for the 5.7x28. I'll try to come up with a starting point for one of these powders and get some projectiles.

01-15-2006, 07:47 AM
I have some 44 magnums I need to chorny this afternoon so I pulled 10 55 grain projectiles from some 223 ammo I had and loaded them in 5.7x28 cases. I loaded 2 each with 3.2, 3.4, 3.6, 3.8 and 4.0 grain of HS6. If they shoot at all and halfway accurate then I'll start chronying them. I'm really just looking for a starting point. I've killed one chrony already so unless I can at least hit the target I won't endanger my chrony.

01-15-2006, 07:26 PM
I fired the above rounds today. I only got data on the 3.4, 3.6 and 4.0 grain loads so here are the results. Remember I only loaded 2 of each to try and get a starting point.

3.4 grain Avg- 957 Rd 1-1001 RD 2- 914
3.6 grain Avg-1032 Rd 1-1072 Rd 2- 992
4.0 grain Avg-1137 RD 1-1141 RD 2-1144

All rounds shot about 6" lower that factory loads or my normal reloads. The good news is that all rounds fired well and the gun cycled perfectly. I guess, since the speed of sound is about 1100 fps, a max of about 3.7 grains of HS6 would do it. I'll load some this week (at least 15 or 20) and get some more data.

Evan Stevens
01-16-2006, 04:05 AM
Did you have any signs of high pressure? I would like to get 1600fps out of a 55 grain bullet. I am not concerned about subsonic. 1600 fps would give 312 pounds of energy. Due to the avaibality of 55 grain fmjbt bullets this would be the most economic round to reload for training, and not a bad round for coyotees.

01-16-2006, 05:34 AM
There were no signs of high pressure. There was almost no recoil at all. I'm not sure how the slide cycled but it did every time. My standard 5.7x28 loads have a tendency to flaten the primer but none of these primers flatened. I pulled these projectiles from some 223 ammo but I ordered 100 gameking bullets from Midway last night. They should be here by next weekend and I'll load some more. I'll load some at 3.7 grains for the subsonic and go a bit higher to try for 1600 fps.

Evan Stevens
01-16-2006, 08:56 AM
If we can get 1600 fps from a 55 grain bullet that would be awesome. I think the 196 only goes 1600 fps with a 40 grain bullet. In the PS90 this load would do fine also probably 1800 fps @ 396 pounds of energy. The minimum energy I want to shoot is 300 lbs. I wonder what we could do with 50 grain bullets 1800 fps @ 359 lbs? From what I have noticed most loaders are only trying 35 and 40 grain bullets. I think we can get 2000 fps from a 45 grain bullet. I cant wait for my case holder for my trimmer so I can get started. I don't think we will get anything heaiver than 55 grains to work properly. This round needs mega speed to stabilize the bullet. Probably 1600 fps minimum as this is what the watered down 196 is clocked at.

01-16-2006, 05:22 PM
The 55 grain bullets I shot at 900-1000 fps seemed to be stable. The hole in the target was perfectly round and the group would have been OK if I had found my aim point a little quicker. I plan to load a lot of 55 grainers as soon as my order comes in.

01-18-2006, 05:40 PM
Try the MO193 at 50 yd.

Why? What are you expecting?

Evan Stevens
01-18-2006, 11:18 PM
So, cheaper to load 55 grainers would be acceptable for training? I will load some of them soon, as I have tons of 55 fmjbt laying arround for my 223 loads. This is good news to me as I like to practice as cheaply as possible. Less money=more practice I do like about the same recoil as my service rounds in my training rounds. Hopefully we can get the same POA out of this.

01-19-2006, 04:59 AM
The speed of sound on a "perfect day" @ sea level is 1140. As you go higher in altude the speed of sound takes higher speed to reach. Below sea level it get slower.
But not by much only a few %.
Calculating the speed of sound use to be kind of like a hobby of mine, I didn't use it for ballistics. I used it for automotive engine intake designs.
But any way, does any one know the rifling used in these pistols?
If it has a barrel like an old 22 hornet or 218 bee with 1 in 16 rifleing then it won't stabilize a bullet much past 100m. Those barrels were made for 46gr or lighter bullets.
If it has 1 in 14 rifling like my mini14 and old model M-16's then it will work perfectly with 55gr bullets, but it won't work with 62gr bullets like the SS109. They will not shoot as good as lighter bullets.
I bet the 5.7 pistol has 1 in 12 or faster.
That should stabilize bullets all the way to about 65 to 70gr.
Then you have 1 in 9 and the insane spin 40 gr bullets apart out of a .223rem 1 in 7 barrels.
With those barrles the bullets tumble and go crazy better when they hit something.

01-19-2006, 11:27 AM
The twist rate is specified in the manual, 1 in 9".

1000fps is pretty close to the optimal speed for sub-sonic bullets. Any faster than that and the bullet begins to destabilize in flight as the shockwave builds.

Bullet stabilization also depends on velocity, as well as twist rate. (RPM varies directly with Velocity.)

The other variable is really length, not weight. Weight is commonly used, but assumes a lead-core construction. A barrel that will stabilize a 55gr lead-core bullet won't necessarily stabilize a 55gr copper solid.

01-22-2006, 08:11 AM
Her are the rsults I got yesterday. Unfortunately 12 of my cases split. I don't think it was from high pressure I've just reloaded them too many times. I don't have anymore once fired cases but I do have 10 twice fired ones I will reload and test. I plan to buy some more from e-bay but it will take some time so any comments or suggestions will be appriciated.

I also fired several using AA7 powder but the results were inconsistant. This could have been due to almost half the cases splitting. I don't think it was high pressure because the primers did not flatten or crater.

04-24-2007, 01:34 AM
the danger is in loading too little powder not too much. Secondary explosive effect and all. With magnum primers and moly coated bullets my rifle is working great. Thanks again for the original post. Saved me a lot of time in trail and error loading.

Medula Oblongata
04-24-2007, 01:39 AM
you are quite welcome, I'm glad to help :)

However, I have a new loading for the SS MO193.

But I won't post it here...

It's proprietary now.. :)

If you want some, you'll just have to slap down the green.. We'll charge the same as what LE departments pay. Do some research, you'll find the price quite reasonable.. :)


Charlie Foster
05-02-2007, 06:14 PM
I went out last weekend and used the following.

PS90 with 1-7" Twist CMMG barrel AWC Raider Suppressor barrel length 10.3"
FN 5.7 X 28 once fired trimmed to minimum length. Base diameter .313"

4.0 grs 3N37 55g FMJ Winchester WSR primers OAL 1.58 20 rounds fired.

A 1390 Hi 1491 Low 1305 ES 185.6 SD 38.9
Very accurate load cycled perfectly and did not stretch brass Base still .313"

6.0 grs 3N37 40 gr Sierra Blitzking OAL 1.58" WSR 20 rounds fired

A 2142 Hi 2195 Lo 2096 ES 98.9 SD 25.4
Good groups some stretching base measured .315" and is pretty hot. Functioned each and every time.

3.2 grs HS-6 55gr FMJ Winchester WSR OAL 1.58" 25 rounds fired

A 1030 Hi 1074 Low 975 ES 98.3 SD 28.0
reliable operation and very quiet. Hit about 1" lower than 40 gr load brass hadly stretched and base measured .313

6.0 grs 3N37 Sierra 40gr HP WSR OAL 1.55" for good neck tension since short bullet. 25 rounds fired

A 2077 Hi 2131 Lo 2032 ES 99.0 SD 26.7
Just like the blitz. Good accuracy but stretches brass. Reliable function.

55gr FMJ Winchester OAL 1.58" AA#7 powder WSR primers 10 rounds per step
Charge Velocity
6.1 grs A 1647 Hi 1689 Lo 1623 ES 65.8 SD 21.9
6.2 A 1649 Hi 1714 Lo 1625 ES 89.2 SD 28.2
6.3 A 1715 Hi 1771 Lo 1676 ES 95.0 SD 33.3
6.4 A 1760 Hi 1810 Lo 1726 ES 83.6 SD 28.7

I would not go beyond 6.4 the pressure signs were starting to really show and it is a pretty hot load. It functioned at all loads with no failures. Accuracy was not as good as the 40 gr loads would hold about 3" at 25 for the most part. I think the load to use would actually be 6.0 grs.

30 gr Berger HP OAL 1.58 3N37 CCI 400 small pistol primers 10 rounds per step
Charge Velocity
5.6grs A 2211 Hi 2259 Lo 2163 ES 95.9 SD 36.2
5.7 A 2221 Hi 2256 Lo 2194 ES 61.9 SD 19.1
5.8 A 2286 Hi 2343 Lo 2237 ES 105.5 SD 29.4
5.9 A 2319 Hi 2361 Lo 2269 ES 92.4 SD 28.9
6.0 A 2351 Hi 2387 Lo 2308 ES 79.2 SD 27.2
6.1 A 2367 Hi 2382 Lo 2335 ES 47.3 SD 16.9
6.2 A 2409 Hi 2446 Lo 2379 ES 66.9 SD 20.9
6.3 No Data
6.4 A 2478 Hi 2533 Lo 2453 ES 80 SD 26.0
6.5 A 2459 Hi 2508 Lo 2453 ES 124.7 SD35.7

5.6 grs was very accurate. All 10 rounds in 1.5" and mild doesn't stretch brass. Above 6.2 is brutal on brass with base at .315" and stretching doubt you would get many reloads. All loads did function in the PS90

40 gr Sierra HP OAL 1.55" AA#7 10 rounds
Charge Velocity
7.0 No Data
7.1 1 round 2013
7.2 A 2086 Hi 2124 Lo 2058 ES 65.6 SD 23.3
7.3 A 2060 Hi 2099 Lo 2025 ES 73.9 SD 28.2
stopped after this brass stretched and did not gain any more velocity wish I would have info a 7.0 grs but feel AA#7 really not the best powder for light bullets. I would use 7.0 grs though all functioned but again the pressure signs were obvious.

I think that AA#7 is a good powder for 55 gr loads but 3N37 is best for 30-40 gr bullets. All functioned but remember a 16" barrel will develop more pressure than a 10" barrel so don't jump on max loads or you may be sorry. The subsonic was very quiet and would recommend everyone with a suppressor use it.

The no data was caused by the Sun being at the right angle and interrupting the cronograph. It was a PACT by the way.

05-02-2007, 06:58 PM
Welcome to the forum.