🔬 NEW R&D Project, the EASY part was deciding where to find INFO 😎

[MustangAR]

Here's the project in a nutshell, MAKING HEAVY BOOLITS for a Subsonic 10mm Project.
Sounds like an oxymoron, why would anyone want subsonic 10mm? GET A FOUGHTY!!! 🤣🤣 Well, the 40 S&W is the little brother of the mighty 10mm and my son and I ventured off the beaten path a few years back. 10mm was the right way to go, no doubt. I have had a few 10's and he recently bought a Sig P220 and a Kriss-Vector both in 10mm. Great purchases, and he has a "can" in ATF Jail awaiting a stamp. The can works pretty well, but true subsonic rounds would really make it SHINE. Hence the Heavy Boolits. I am thinking 220gr and UP, but I have seen no molds, only one round (230gr, discontinued) and that is it. So here are my options:

1. Custom Mold
2. 41 Magnum Mold (largest at Midway is just 220 :P ) then resize
3. Swaging
4. .375" tungsten with a copper jacket (but it is too easy to get way over 300gr with this!)
5. Find heavy 41 Mag cast boolits and resize

We want true subsonics, so reduced case volume with an extra long boolit is fine, we have 10 powders on the way and a good number of load recipes available. Starting at the low end on any loads, then working up yada yada, ;)
Any peripheral advice by experienced subsonics experts is welcomed but I primarily want just info on the best way to proceed for an extra heavy cast projectile. I'd like 250gr and I am pretty sure we can get a proper case volume, acceptable noise and velocities.

Thanks in advance for any help!

[MustangAR]

I'm ready to move this inquiry to the proper section once it's settled.
I thought about swaging but that is lower on the list, as it would require a whole new class of equipment I guess...

[ewlyon]

GT bullets has a 250gr 41 cal hollow point you could try resizing.

[475AR]

I'm ready to move this inquiry to the proper section once it's settled.
I thought about swaging but that is lower on the list, as it would require a whole new class of equipment I guess...
Go to accurate molds, Tom has several molds that will work. I designed a 10mm 240gr that works @ 1.25" COL. depending on what magazine you plan to use you have to watch how much of the bullet goes into the case otherwise you bulge the case @ the web.
Here is the one I designed, it is designated 40-240D.
http://www.accuratemolds.com/bullet_detail.php?bullet=40-240D-D.png
As can be seen it is designed for coating (no grease grooves) , I use hi-tek coating. Here is a bullet and a dummy round loaded @ 1.25" COL.
242477
I have shot several in load development and they feed and shoot great thru my DI 10mm AR15, I have only shot a couple thru my Kriss 10mm to test feeding and had no issues so far. I have yet to settle on a load and hope to chronograph some soon.
If you want heavy jacketed bullets I can't think of anyone that makes over 200gr. As you stated you could get into swaging it is expensive.

[JonB_in_Glencoe]

what about a 40 cal rifle bullet mold?
https://www.midwayusa.com/product/1010241475/lyman-2-cavity-bullet-mold-403169-40-caliber-406-408-diameter-240-grain-flat-nose

[MustangAR]

GT bullets has a 250gr 41 cal hollow point you could try resizing.

Perched right at the top of my weight limit, for the R&D stage! These are reasonably priced and prolly easy to resize. Any input on resizing? I also see they make a 240gr Elmer Keith boolit. Thanks @ewlyon!

[MustangAR]

what about a 40 cal rifle bullet mold?
https://www.midwayusa.com/product/1010241475/lyman-2-cavity-bullet-mold-403169-40-caliber-406-408-diameter-240-grain-flat-nose I will keep that in mind... Thanks!



Go to accurate molds, Tom has several molds that will work. I designed a 10mm 240gr that works @ 1.25" COL. depending on what magazine you plan to use you have to watch how much of the bullet goes into the case otherwise you bulge the case @ the web.
Here is the one I designed, it is designated 40-240D.
http://www.accuratemolds.com/bullet_detail.php?bullet=40-240D-D.png
As can be seen it is designed for coating (no grease grooves) , I use hi-tek coating. Here is a bullet and a dummy round loaded @ 1.25" COL.
242477
I have shot several in load development and they feed and shoot great thru my DI 10mm AR15, I have only shot a couple thru my Kriss 10mm to test feeding and had no issues so far. I have yet to settle on a load and hope to chronograph some soon.
If you want heavy jacketed bullets I can't think of anyone that makes over 200gr. As you stated you could get into swaging it is expensive.

This is the best so far, only thing I'd like better is a ready made .401 boolit :D I also appreciate the data points.

As a side note, is the DI 10mm upper readily available? I looked at that a few years back and only the blowback was around, and I did not really want that. Very sensitive to buffer weights, as I recall. If I'd get an AR-10(mm) I would likely forego the KV. But it is calling my name :D

[Outpost75]

Accurate has several heavy 10mm designs for the Ruger Blackhawk. I also use them in a 10x25mm revolver using necked down .44 Russian brass. John Taylor did the work, has the tools and can make dies also.

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[475AR]

I will keep that in mind... Thanks!




This is the best so far, only thing I'd like better is a ready made .401 boolit :D I also appreciate the data points.

As a side note, is the DI 10mm upper readily available? I looked at that a few years back and only the blowback was around, and I did not really want that. Very sensitive to buffer weights, as I recall. If I'd get an AR-10(mm) I would likely forego the KV. But it is calling my name :D

Yes, the DI 10mm is available there are a couple of companies making them. Macon Armory (Rudy) has one, I have no experience with Rudy's uppers. RMW XTREME (Ron) also has them and has been making them for several years. RMW XTREME happens to be local to me and I have several of Ron's DI uppers in calibers from 9mm to 50AE.http://www.rmwxtreme.com/ I have the Kriss 10mm as well and love it also. Both shoot very well and both suppress well also. I run a TiRant 45 suppressor on both. I am not a fan of the blowback AR because of the need to run heavy buffer springs and buffers to get them to run. One thing I like about the AR pcc is I can run several uppers on different lowers, I have several lowers that take greasegun mags, glock mags as well as modded .223 mags. The DI AR uppers have come along way in the last few years and are hard to beat IMO. Having shot both with the same ammo I think the DI AR 10mm has less felt recoil, but the Kriss is close and is fun to shoot and always draws a crowd when I go to public ranges.

[MustangAR]

Accurate has several heavy 10mm designs for the Ruger Blackhawk. I also use them in a 10x25mm revolver using necked down .44 Russian brass. John Taylor did the work, has the tools and can make dies also.

Accurate? I'm sorry, can you supply a link or the full name? Sounds like what I want, ready made cast! Thanks @outpost75!

PS: Looks like a sweet setup!

[MustangAR]

Yes, the DI 10mm is available there are a couple of companies making them. Macon Armory (Rudy) has one, I have no experience with Rudy's uppers. RMW XTREME (Ron) also has them and has been making them for several years. RMW XTREME happens to be local to me and I have several of Ron's DI uppers in calibers from 9mm to 50AE.http://www.rmwxtreme.com/ I have the Kriss 10mm as well and love it also. Both shoot very well and both suppress well also. I run a TiRant 45 suppressor on both. I am not a fan of the blowback AR because of the need to run heavy buffer springs and buffers to get them to run. One thing I like about the AR pcc is I can run several uppers on different lowers, I have several lowers that take greasegun mags, glock mags as well as modded .223 mags. The DI AR uppers have come along way in the last few years and are hard to beat IMO. Having shot both with the same ammo I think the DI AR 10mm has less felt recoil, but the Kriss is close and is fun to shoot and always draws a crowd when I go to public ranges.

Great data, I am gonna see if I can assemble an AR-10(mm) for less than a K-V ��
I have lots of AR parts, so it's pretty likely. If I don't count the prior outlay!

THEY HAVE TOKAREV UPPERS!!!
Crazy Stuff, that RMW, THANKS, @475AR!

[lar45]

You might want to seat a bullet dealer and dealer until you get the bulge, then you'll have an idea of what the max bullet length will be.
Deeper, **** spell check on the phone...

[MustangAR]

You might want to seat a bullet dealer and dealer until you get the bulge, then you'll have an idea of what the max bullet length will be.

Copy That, and I am thinking after this first round of 250 and 240 we might just see what the limits are of OAL, grain weight, case volume, and powder charge. Working with SUBS should be a lot safer than pushing for max power loads, but I still foresee a possibility of getting a dangerous charge with a too heavy or too deep bullet.