300 Blackout cast load data

[Mike Hughes]

The Lil Gun did good at 50 yds, but not as well at 100 yds, I failed to upload the 100 yd groups of Lil Gun. The reason I was wanting to ruduce, is I have seen where people comment that accuracy goes away after about 1800 fps with cast boolits. Yesterday, I loaded up some Lee 312-155. I'm not too sure about my chronograph, the lil gun velocities are not consistant with the 150 gr boolits. Here is the readings I came up with

Lil gun 15 gr 1990 fps
Lil gun 15.5 gr 2050 fps
Lil gun 16 gr 2070 fps
1680 18 gr 1760 fps
1680 19 gr 1810 fps
Reloader 7 17 gr 1675 fps

With the Lil gun, the 15.5 and 16 gr loads were pushing the primers out of the pocket and were flattened out. About half of them popped out.


It's hard to see, but the 17 gr of reloader 7, 4 of the five shots were touching.

[Mike Hughes]

Well the results weren't as well as I had hoped. The best I got was still around 15.5 to 16gr of H110 with groups in the 2 1/2 to 2 3/4 inch range. I still have not been able to get any luck at all with Lilgun or 1680. I'm going to try some RE7 and see how that works out.

I did find the upper limit for the Lee 312-155-2R with 2 different powders. COAL of 2.060 with 16.5gr of H110 gave me ejector swipes on a few rounds and 17.0gr H110 popped a primer on the 2nd shot. 17.0gr of Lilgun popped a primer on the 5th shot with some pretty severe ejector swipes on a couple rounds. Both loads were right around the 2050 FPS range.

These were shot from my Savage Axis with a BFG 300 blk barrel.

Jailer
I had similar results with the Lil Gun, at a lower charge, but same fps. I better check my scales (cheap digital) sounds like I may be weighing a grain or 2 heavy

[captain-03]

That RL-7 load looks really good -- I, too, have that mold ... will pour a few tomorrow.

[2wheelDuke]

I didn't have any pressure signs with 16gr of Lil Gun behind a 312-155-2r. Mine were sized .310 and seated to 1.925". I didn't chrono any.

[41 mag fan]

Been looking for load data myself, as I got a CMMG also.
What about for the j-word loads? I'm wanting to set back 10k like I normally do for most rifles i have.

Anywhere I can find data out there for it?

But I also want to try casts thru it, so this info will be useful.

[Mike Hughes]

http://www.accuratepowder.com/wp-con...ckout_Data.pdf
http://www.vsms.org/Forum/Seite_70_B...0_Blackout.pdf
http://www.vigilanceaero.com/CustomR...ta.numbers.pdf

[41 mag fan]

Thanks Mike!! I apprecite it!

[Moonie]

I like 16gr H110/W296 with my 155 .312 lee boolits. Seems to be accurate and cycles well, no pressure signs at all.

[Possum]

I am running the Lee 155gr bullet with W296 from 15-16.5gr at 1800-1900fps. I like the results from 16-16.5grs

[bigfelipe]

I am running the Lee 155gr bullet with W296 from 15-16.5gr at 1800-1900fps. I like the results from 16-16.5grs

Is that checked?

[Possum]

Sorry about the late reply. Yes. That is checked.

[bigfelipe]

Sorry about the late reply. Yes. That is checked.

Thanks. haven't got much going in supers yet. Been concentrating on sub rounds.

I'm running Lee 230gr over 8.2g H110 at about 950fps dead quiet through my AAC Handi with a wet Isis II 45 can...

Had a blast ringing steel at 100-200yds last weekend

[thumbs]

If anyone is still around. What are your sizing that Lee 312-55 to? I see one post stating .310 is .309 to small? I know I'll have to slug the barrel but don't have the upper yet.

[Ramson222]

If anyone is still around. What are your sizing that Lee 312-55 to? I see one post stating .310 is .309 to small? I know I'll have to slug the barrel but don't have the upper yet.

.310 with powder coat results in jammed rounds in mine. .310 lubed should be fine, the problem with the powder coated rounds is that the nose becomes to fat to chamber properly. I'm trying to get a group buy going for a bullet much like the lee 312-155-2r in the mold discussion area. This would be specific to the blackout and specifically designed for coating so that the nose does not exceed .308 in diameter. so far the honchos are waiting on another mold to finish brewing. Then they will get on it. It would be great if you would jump on board.

[Texas by God]

Mike Hughes- thank you so much for posting your accuracy results using cast in the 300 Blackout. I've been trying to get someone to do that for quite a while. My results pretty much look like yours. My blackout shoots jacketed bullets wonderfully, but the accuracy with cast has not been up to my standards. My newest AR is a 7.62 by 39 and it has been brilliant from the get-go. I believe it is a function of the rifling twist although I could be wrong. A blackout is a fun little round and I'm not getting rid of it but I have other rifles that shoot cast with much less work. I only use Super Sonic in Mine by the way.

Sent from my SAMSUNG-SM-G930A using Tapatalk

[Gunnut 45/454]

I have the same CMMG 16" 1-7" Twist carbine setup you have. My cast loads using the Lee 150 FN , 170 gr FN or the Lee 155 gr all with Lil Gun ! I run 15 to 16 gr all function perfectly and are 1-1.5 inch groups at 100 yards.

[Conditor22]

In an H&R 300 AAC BO YMMV
300 AAC BO H110 15.3 grn LEE 150 grn 0.309
300 AAC BO H110 12 grn LEE 150 grn 0.309
300 AAC BO 700X 4 NOE 232 FN 0.309
300 AAC BO TB 4.5 NOE 232 FN 0.309
300 AAC BO 700X 4.1 NOE 247 FN GC 0.309

[Bodydoc447]

Does anyone use a Lyman top punch to size the Lee 312-155-2R bullet?
Thanks, Doc

[Krh1326]

I see several guys running 15 - 16 grs of H110 for cast .300 blackout, and posting good results.
I am tinkering to find the right combo, for me. I just measured 15 grs of H110 into a case, and found that I’m up, into the neck. I figured I measured wrong, so dumped it out, and checked and double checked… still up into neck.

Is H110 meant to be compressed? And that was 15 grns, didn’t even bother with 15.5 or 16, at this point, until I research about compressing the charge.

I am new, so maybe I am missing something, but doesn’t seem right, so I’m asking.

I have read that other powders are better, but for the moment, I’m handcuffed to the H110. I’m also stuck, for the moment , with a Lee C309-170-FP (using hornady GCs ) ( I will have the 312-155 soon, hopefully ) but for now, I’m guessing my start should be around 10 grs…. But for the time being I’m seeing posts with 15-16 grs of H110 , and even one for 16.5 for the 155 gr boolits.

Is this safe to compress the powder?

[popper]

Is H110 meant to be compressed?
nope nor downloaded excessively. How long is your drop tube? 15gn shouldn't be full load. I use 15gr under a 145 PB, 17 under 145 GCd. 15gr should be a good load for the 170, start at 14.