Home Forums Hunting & Shooting AR and Tactical Rifles 300 Blackout reloading

Specifically using the Speer 125 grain TNT bullet and a AR-15 SBR …. Can’t find any published data ( even from Speer ) regarding cartridge over all length and this bullet . Any help would be gracious .

This will give you a good starting point

http://www.hodgdonreloading.com/

I have no personal experience with the bullet, but this may provide some help: http://www.300blktalk.com/forum/viewtopic.php?f=140&t=107161

look at H110, 17.5 is max for 125, so probably 17 grains of H110. I would consider shooting lighter bullets, the 110 grain bullets in the BO are in my opinion a good spot to land on.

A little off subject, But has anyone used Top brass. The resized 223 into 300 Blackout. I bought some from a guy on here and one out of ten will chamber in both my rifle and SBR.

https://sierrabulletsblog.com/2017/12/21/sierra-bullets-300-aac-blackout-load-data/

The Sierra data lists COAL, you should be able to get an idea...



Just got my 300 BLK Bbl from Bullberry, shot it for the first time today....

Will be trying the Hawk 200grn RN, soft jacket, and this.....

That's 230 grns......

All sub-sonic of course.....

Sorry, that doesn't help much for a magazine gun...

I have used a lot of those in the 300 Blk - 2.000"-2.060" is where I found it to work the best. Lil'Gun or H110 are both good performers with this bullet.

This is an accurate bullet that holds together more than you'd expect in this low velocity cartridge; it doesn't act like the varmint bullet it's designed to be in the 308 or larger cartridges.

Hodgdon used to list 18gr of Lil'Gun as max with 125gr bullets, but they have since increased it to 21gr. This is a good load in my experience, with two different AR's. I also load it to mag length, and it runs fine in both.

I shoot 125gr Nosler BT, and pigs hate them.

BTW Midsouthshooters is having a good sale on Nosler brass, right now:

https://www.midsouthshooterssupply....int300-aac-blackout-bulk-brass-500-count

I used the 125 nbt over PP300MP on a texas pit hunt. MV was 2250 from a 16" ar and they worked well on 3 hogs. I have a bunch of the 125 speer tnts I bought for half price but I haven't tried them yet. With the 300 bo seating depth can really change pressure fast like a pistol. Set the depth for what feeds well from your mags and then work up to pressure.

Bb

I have a bunch of the Missouri bullet 245 gr lead flat nose bullets for subsonic loads, but I don't have a suppressor on my 10.5" Blackout barrel. Is there any benefit to loading these subsonic, or should I load them a little hotter? What would ya'll do with these bullets? (I know yer gonna say buy a suppressor, but I can't afford a suppressor at this time).
Thanks; John

In your situation, I wouldn't use them at all.

If you're not going to shoot them subsonic & suppressed, there's really not much point in loading them at all, other than to find out what a subsonic load feels like. There is no practical ballistic advantage to them compared to full power loads with the correct bullets, and it still sounds like a gunshot without a suppressor.

Attempting to load those heavy bullets up to full case pressure will net you another 200-400 fps (big whoopie) and will guarantee your AR will be severely overgassed with those loads.

Since I already have a ship load of theses bullets, would there be any downside to loading these to sub-sonic speeds, shoot them at .45 ACP level. close range rounds. Would there be any downside to using them like that, or should I resell them and buy 110-125 gr bullets with the money?
thanks John

Other than the fact that they have ballistics like a handgun and not a rifle, no.

No real downside, except that there isn't much point without a suppressor. In your shoes I'd consider selling or trading them to someone for 110-125gr jacketed bullets.

Yeah, That's probably what I'm gonna do. Anybody want to trade some bullets?

I've shot a buttload of the TNT's h110 / 296 is Top Choice accurate #9 makes a good substitute

....

For supersonic I've had great luck with pp300mp.

Bb

OK, so I was thinking.....


But, didn't... Waiting to find some Hornady 190 Sub-X bullets. Got to thinking, again, that a flat nose might thump nicely. Then saw the 125 HP/FN Sierra and actually located a box,

So, didn't consider such a short bullet and fast twist, going to try in a bolt gun:
Subsonic, H4198, Sierra 125 HP/FN and 1in7" twist.

Hmmmmm? 100 yard deer neck wrecker or inaccurate CF?

I'm going through a 1000rd box of 205gr Amax loads right now. Accurate as hell, but haven't had a chance to try it on game yet. Not sure I will either, to be honest. To each his own, but I still like "too much gun" for hunting.

Fun little plinker though.

Mines a 700AAC, with the sporter contour barrel off a model seven aac. Faux-Ti stock with a grayboe DBM, fed by MDT .223 mags.
Target I shot today sighting in a SSMQ6x I stuck on it.
*Edit to add* 80 yds, not 100.