Just to get the discussion off from other threads, post your thoughts, experience, questions, pictures etc. here.

To answer NTXBowfisher, yes, the 208gr A-Max with 10.5gr of H4198 is a subsonic load. Factory 220gr subsonics are enough to put a hog down but shot placement is VERY important. I doubt many bullets will expand when shot subsonic.

thats the only down fall i've heard about the sub-sonic loads, very low expansion on impact.

what do think is the maximum kill range when shooting sub-sonic loads out of a 16" barrel w/ suppressor?

Barrel length is irrelevant on the equation as you want to stay under 1100fps. I would say 200 yards and that is purely based on trajectory. Energy is preserved quite well, 509ft-lb at muzzle, still 445ft-lb at 200, 398@400.

300 Blackout 10.3" barrel with YHM suppressor, Zeiss Diavari scope:




300 Fireball 16" barrel, Bushnell Elite 6500 scope:



Subsonic ammo loaded with 220gr Speer HotCor bullet:

I have been looking for load data for my BLK in supersonic rounds. I have been testing 125 Sierra SP's out of it but I can't make them group very good. Been using H110 powder and my last test was with 19.5 grains. Can someone post their data for super sonic stuff?? I'm thinking of pushing up over 20 grains to see if it works better. I still have not seen any bad pressure signs.

What kind of velocities and SD are you getting with each load? I have loaded some 125gr TNT's with H110 but only did a quick sighting in with them.

Don't have a chrono. I started real low around 14.5 gr and worked up to 19.5. Still no pressure signs but groups are not good at all.

Chrono would help. Before you up the load, I would try a different powder.

Like What???? I can't find any published data for the BLK!

Here's load data from Sierra: http://listmequick.com/300/Sierra300whisper.pdf

Cross-reference powder from this table: http://www.vihtavuori-lapua.com/pdfs/Burning-Rate-Chart.pdf

N110, H4198, AA1680, RL7, 2400 etc.

Accuracy load: Vihtavuori N110 16.4gr, Velocity 1900fps.
Hunting Load: Vihtavuori N110 17.7gr, Velocity 2000fps.

Marked for Future Reference

Punching paper is one thing with the 300 Blackout but with those heavy projectiles and high sectional densities when shooting live animals you will kill a few and wound a lot. There will be very little expansion at any distance.

Hornady is already on this problem, they are going to have at least one selection in both hunting and TAP lines by third quarter. Suposedly Ballistic tip and HP somebody posted about some company making soft points as well. Only down side is they will be super-sonic loads

I built this gun for super sonic rounds more than anything. I wanted an AR with more punch on a hog, but didn't want an AK.

Ok, I finally did it. Got a chrony ordered, should be here Monday. Updates and pics of the rifle to follow next week. I know all of you can't wait!

I have about 100 rounds of 125gr TNT loaded with H4198, now I just need to find time to go shooting. Good call on the chrono, it will help you out a lot.

Here's myt 300BLK. This is a Smith and Wesson MP15 that got damaged when my house burned last year. Buddy of mine sandblasted it and painted it with Duracoat for me. Got the barrell from Delta Comapany Arms. Has a Millet DMS scope w/ Burris PPER mount. Got my Chrony for Father's day this morning and fired a test round. 19.1 grains of H110 with a Sierra 125 SP turned out 2257fps! So I guess I had too much powder. Waiting on Uncle Sam to come through with my tax stamp so I can play quietly!

Story of my life...nobody cares.

I keep forgetting to check this section since I don't reload. That looks great, glad you where able to salvage the rifle.

I just keep getting more and more depressed as I'm waiting on all my stuff to come in.

Spikes lower for SBR waiting for it to get here. Need serial from lower to wait some more at BATFE for form 1 to clear.
Barrel from DCA on order
AAC 7.62SDN6, Form3 transfer awaiting approval at BATFE, Wait some more once it gets here for the form 4 transfer to clear BATFE

plenty of ammunition on order (got a single box in yesterday)
My Boss messed with me and ordered an inert 762SDN-6 and had me open it I was so happy for all of a minute till I figured it out.

This is the longest running project I have ever tackled as I started around January.

I know this is about 300BLk, I think the caliber is super cool, all be it highly specialized. I've also been looking at 6.8spc, which looks pretty useful on hogs and deer out to 250y. But lately, I've really been wanting a 7.62x39 (soviet) AR upper. I think that pretty much sums up my order of purchase too, 7.62x39 upper, then 6.8spc upper, then 300BLK. I may never even make it to 6.8spc though.

That should perform nicely on animals

Any updates guys ?

Finally for my Lower and my 762SDN-6 Awaiting clearance on Form 1 and 4.

Only thing left now is Another Spikes BCG and the Barrel from Aaron at Delta Company Arms, Great Guy to deal with BTW.

Lets keep this thread moving

I have put my load development on hold until I get my press mounted in the house. (too hot in the shop) I have a chrono now so it should go faster.Should have my suppressor soon, CANNOT WAIT!