.458 subsonic rifle bullet casting/coating

[4g64loser]

I am not up on this area of specialized work. A guy I know may be doing a bolt gun in 450 bushmaster with the express intent of pushing long for.caliber bullets in a subsonic application. My work is all jacketed stuff so I'm going to throw this out here for help from our resident casting/coating experts. Below are his questions to me that I'm not qualified to answer.

1) Most places that advertise custom mold making limit to 1.4" or so on the bullet length. I haven't reached out to MP molds specifically yet, but I didn't even see custom design fab on their website. I'm wondering if the length alone puts my project in an unusual category requiring a specialist

2) I'm having trouble finding clear ideas on optimizations for purely-subsonic designs. I see lots of ideas on blogs but they often contradict each other

3) I *think* I want to go the route of powder coating, and using a bore-rider front with a driving band starting in the middle so that I can remain compatible with a stock reamed chamber in 450 bushmaster or 458 socom. I gather that most people using powder coating are using it in non-precision supersonic applications with comparatively blunt nose profiles. I'm wondering if powder coating is the right path, if extra nose finishing is required for my use case, and if I need to size the bore riding section.

 

[outrider58]

Do you know Andrew from Amalgamated Cartridge Co.? He used to make TK Defense's reloads and sold his reloads at most of the mid-Maryland gun shows. I was recently told he was out of the business now, but he's the guy you'd probably need to talk to if you know him.

 

[4g64loser]

Do you know Andrew from Amalgamated Cartridge Co.? He used to make TK Defense's reloads and sold his reloads at most of the mid-Maryland gun shows. I was recently told he was out of the business now, but he's the guy you'd probably need to talk to if you know him.

I bought his jacketed 300blk subs when I still owned a blk upper. Shot ok for a carbine. This guy is specifically looking at pushing subs in a 458 bore and I just haven't done it. I've only done jacketed and mostly high velocity 458 (45-70 hot rodded to No 1 pressures, 458 win mag, etc.).

 

[outrider58]

I bought his jacketed 300blk subs when I still owned a blk upper. Shot ok for a carbine. This guy is specifically looking at pushing subs in a 458 bore and I just haven't done it. I've only done jacketed and mostly high velocity 458 (45-70 hot rodded to No 1 pressures, 458 win mag, etc.).

Andrew was a constant tinkerer, including developing .223 PC sub rounds as well as .308 subs. I would be surprised if he didn't have an opinion worth listening to.

 

[4g64loser]

Andrew was a constant tinkerer, including developing .223 PC sub rounds as well as .308 subs. I would be surprised if he didn't have an opinion worth listening to.

Good thought.

I tried some of his 308 subs but the sako factory stuff (and my clones of them using 200gr lapua flat base jacketed stuff) shot better.

 

[blazing lead]

450Bushmaster.net • View topic - Heavy Cast Subsonic Bullets (500 grain) Range Report

Here's something I saw about 500 gr subs with PC it might have some insight as well. Good luck it sounds like a cool project.

 

[ohen cepel]

I think he may run into many issues, barrel twist being one of them as he goes heavy.

I did some of these things in the past (not with 450BM), but other calibers and I likely won't do it again as, in the end, it didn't get me much aside from annoyed. By that, I mean it is better to find a heavy round which can but pushed to the speed of sound. Looks like a 395gr is going to be right around sub, and there is data for that. I think I would go with that and be done with it. Getting x gr more weight, but giving up fps may not be worth it.

Going heavier/longer could create stability issues also which he won't know till he has bought a custom mold, etc.

 

[Growler215]

I bought the Ruger 556 AR 450 Bushmaster specifically because it had a 1:16 twist. I enjoy shooting factory 395 gr Sub-X rounds through it, and have bought some of these bullets to reload but haven't gotten around to it yet.

Unfortunately, unless I chop a few inches off the barrel (after registering it as an SBR), I can't hunt deer with it in MD with these 395 gr bullets. Need 500 gr bullets moving at 1040 fps to make the required 1200 foot lbs of muzzle energy for a subsonic rifle that is not an air rifle. I've seen the blog where people have done it. From what I can tell, would need to get .458 500 gr cast bullets (Midway sells some, but they come with lube that would need to be removed) and swage them down to .452 (450 Bushmaster bore diameter) before powder coating. I'm sure most people cast their own. Hornady has load data getting the 395 gr bullets up to 1650 fps, so there might be room to safely get a 500 gr bullet to 1040.

 

[ohen cepel]

Hodgdon shows 1067fps max for a 395gr. I wonder what the deal is if Hornady is saying 1650fps...........

https://www.hodgdonreloading.com/reloading-data-center

 

[john_bud]

No 454 experience, but i just powder coated 250 bullets at 0.358 for my 350 legend. Ive shot 4-500 at 1600fps and 2-300 subsonic from a bolt gun. I'm now figuring out subs in the AR platform.

The PC process is simple. I spent $10 on equipment + Eastwood powder. Goodwill toaster oven was $4 on senior day. Then walmart had a silicone mat for the tray.

I shake a SMALL amount of powder with 75ish clean dry bullets. Quick spray and wipe with brake clean. Then shake for a minimum 60 seconds. Time it. i use an old dishwasher detergent plastic with a closing lid. and i shake aggressively Then tweezers to stand them on the matt on the tray. Cook at 400F 20 minutes. Carefully pull out and dump in water.

Makes way less smoke than lube.

 

[Biggfoot44]

.450BM is .452 . .458SCOM is .458 .
There are an uncountable number of molds for heavy bullets of .458/9 .

Buffalo Bore offers loaded 500 gr @ 1075 fps .

 

[John from MD]

I am not up on this area of specialized work. A guy I know may be doing a bolt gun in 450 bushmaster with the express intent of pushing long for.caliber bullets in a subsonic application. My work is all jacketed stuff so I'm going to throw this out here for help from our resident casting/coating experts. Below are his questions to me that I'm not qualified to answer.

1) Most places that advertise custom mold making limit to 1.4" or so on the bullet length. I haven't reached out to MP molds specifically yet, but I didn't even see custom design fab on their website. I'm wondering if the length alone puts my project in an unusual category requiring a specialist

2) I'm having trouble finding clear ideas on optimizations for purely-subsonic designs. I see lots of ideas on blogs but they often contradict each other

3) I *think* I want to go the route of powder coating, and using a bore-rider front with a driving band starting in the middle so that I can remain compatible with a stock reamed chamber in 450 bushmaster or 458 socom. I gather that most people using powder coating are using it in non-precision supersonic applications with comparatively blunt nose profiles. I'm wondering if powder coating is the right path, if extra nose finishing is required for my use case, and if I need to size the bore riding section.

Call Swede Nelson at NOE and ask your questions. As for MP, you can buy what they have on their website.

Accurate molds has a design tool but I don't think he makes sp bullet noses.

 

[Blacksmith101]

Send your buddy and his questions to Cast Boolits Forum they will have answers.

Cast Boolits

This is the dedicated cast bullet forum!

castboolits.gunloads.com

A quick search shows they have at least on thread on the subject:

• .458 socom bullet for subsonic

https://castboolits.gunloads.com/showthread.php?451387-458-socom-bullet-for-subsonic