Subsonic .223

My ideas to share, besides making consistent loads. Check your fire control system. The firing pin needs to strike the same each time. Also remember the bullet is in the barrel longer so your handling and follow thru is important too.

Went down same road couple years ago trying to reach out beyond 200yds with high BC bullets.

Have fun in your quest.
 
If you can run a heavier bullet that could help. Trailboss is a good powder to stick with, as it removes any chance of a double charge. Pistol powders are pretty easy to make a mistake and blow yourself up. Neck tension will also be a big thing to check on.

Some bullets don't stabilize well at subsonic velocities. Usually high bc bullets aren't ideal. Round nose, or more blunt bullets, tend to work better for subsonic applications. I haven't loaded 223 subs, but in 308 that's been my experience.
Okay guys, maybe a silly question but where are you guys finding your info for your loads for your subsonics?? I do reload and have been for a while. But for the life of me I can't find subsonic load data. Shooting an AR 10 sig sauer 308. Could really use the help.
 
Okay guys, maybe a silly question but where are you guys finding your info for your loads for your subsonics?? I do reload and have been for a while. But for the life of me I can't find subsonic load data. Shooting an AR 10 sig sauer 308. Could really use the help.
The formula for Trail Boss is posted on the Hodgson website. Basically amounts to fill to where the base of the bullet stops in the case, start at 70% for a starting load and work up. Works for all bottleneck cartridges. Do NOT use that method for straight wall cases.


The old subsonic pistol powder loads showed up in the Lyman load data for cast and a few other old manuals.
 
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I build subsonic loads for lots of different cartridges. Trail Boss is my go to powder. Before Trail boss used all the typical old style ways to build SubS loads. Since Trail Boss, there is no reason to incur the risk of using pistol or shotgun powders to build SubS loads. I have never had a cartridge that I could not get under an inch at 100 yards with jacketed bullets and under 2" with cast. First step, crimp the loads if shooting cast, do not use gas checks, size your lead to .002 over normal in smaller calibres, as much as.005 over for larger, so for .224, size to .226 then try .227. Next major consideration, use flat nose bullets with wide metplat, much better killing effect. Round balls also work great and have the advantage they lose velocity very quickly so much less carry if using on tree squirrels etc. When tuning a load increase or decrease TB powder charge by .1 grains, you will be suprised how little it takes to really shrink groups or open them up.

In the 22 Hornet, I have loaded 900 FPS with 50 grain Honrady Spire point, under an inch at 100, in the 223, 880 FPS using 70 grain Sierra, under 1" at 100, in the 375 Ruger, 950 FPS us .378 260 grain cast, 1.5 inches at 100. All using Trail Boss powder and this is just a few. Have made cast loads even for the 460 Bee using 410 grain cast at 990 FPS. They shot just over an inch at 100.



308 Round Ball Grouse and Squirrel loads, 900 FPS. These round balls are .312 diameter. The loads I tried with .310 round ball, the groups were three times this size. You want the lead to seal the bore and get a real good bite on the rifling for best accuracy.

View attachment 541999

Round ball groups at 25 yards. Both are 5 shot groups, one on the left is .1 grains more than the 5 shot group on the right.

View attachment 541998
Thanks for the good information
 
Not to derail the posts but just how quiet can a 223 be with subsonic without a can? Got my curiosity going
If you have ever shot 22 rf subsonics like the CCI quiet, or WW Subsonic ammo, TB sub loads are that quiet also. The larger the bore, and the heavier the bullet, the quieter they are. So a 375 sub is less noisy than a 243 subsonic round. What you really notice is how little the sound carries, even just 50 yards away.
 
Okay guys, maybe a silly question but where are you guys finding your info for your loads for your subsonics?? I do reload and have been for a while. But for the life of me I can't find subsonic load data. Shooting an AR 10 sig sauer 308. Could really use the help.
10.5 gr of trailboss and a 220 gr bullet was my standard subsonic 308 load. Kept it around 980 fps, plenty quiet, and hilariously fun to plink steel with.
 
OK here's my situation, I'm trying to run a subsonic 223 bullet. The bullet I'm using is 55g cast lead with a gas check. Right now, I'm using trail boss powder 2.8 grains if I shoot a 10 shot string I end up with one or two shots that are 50 ft per second high or low. I'm weighing each charge, my average velocity is running about 985 this is perfect as it gives me a fairly good and super quiet load, but the accuracy sucks. Does anybody have any thoughts on another direction that I could go with this or another powder to use I know trail boss is widely used in cowboy shooting and I have a lot of it, but I also have red dot, unique and a few others. Just for looking for something that I can shoot that's extremely quiet.
Hodgdon lists subsonic loads for .223 Remington https://hodgdonreloading.com/rldc/?t=1. Have you considered using an air rifle?
 
Anyone use Shooters World - Buffalo Rifle? I believe it's SWs answer to trail boss.

Emailed with the guy there and he said no issues with case capacity and powder position. They had load data for almost every round if I remember correctly.

I bought a lb. Thought I'd try it out in the 45-70, but found 3 lbs of Unique, so abandoned my quest for Buffalo Rifle data. But wonder who uses it and for what.
 
I had a buddy that shoots an airgun tell me that my 308 subsonic and suppressed is quieter than his airgun. I haven't heard his airgun shoot just repeating what told me.
It depends on the 308 load and the air gun, but I'd believe that. If you stay around 950 fps, all you hear is the trigger click and then the bullet whistling. As you approach 1050 (or whatever speed of sound is for your elevation) more and more noise is created.
 
It depends on the 308 load and the air gun, but I'd believe that. If you stay around 950 fps, all you hear is the trigger click and then the bullet whistling. As you approach 1050 (or whatever speed of sound is for your elevation) more and more noise is created.
I run 11 gr of trailboss under 175 gr roundnose. Yes I hear the trigger a slight bullet noise then the thud when the bullet hits. I just don't know how quiet the airguns are, he shoots a Texan.
 
If you have ever shot 22 rf subsonics like the CCI quiet, or WW Subsonic ammo, TB sub loads are that quiet also. The larger the bore, and the heavier the bullet, the quieter they are. So a 375 sub is less noisy than a 243 subsonic round. What you really notice is how little the sound carries, even just 50 yards away.
I have shot the 22 rf quiet rds. Now I am even more curious. thank you for the insight. I appreciate it!
 
I had a buddy that shoots an airgun tell me that my 308 subsonic and suppressed is quieter than his airgun. I haven't heard his airgun shoot just repeating what told me.
I have 308 and 300 blackout subsonic loads that the only thing you hear is the firing pin drop both are way quieter than an air gun. I actually went down this road for a while looking at a large caliber air rifle but they're quite loud and as I already have a number of 308s and 300 blackouts I just couldn't justify the money for something that was louder and I'd have to have special compressors and stuff just to shoot. Also having about 20 lbs of trail boss makes a difference 😊
 
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