Cast bullets in 300 blackout

[wgttgw]

I finally got a chance this morning to shoot my AR-15 300 blackout since work and the weather finally eased up a bit.

Loaded some Lee cast 312-155 (non tumble lube) bullets, sized at .309, lubed with one of my homemade lube (mostly Lucas red grease and beeswax) and seated to the crimp groove.

15.4 gr. H110 did 1850 approx fps average
16 gr H110 did approx. 1950 fps
15.8 gr little gun did approx 1925 fps

Little guns seem to produce the best groups, sadly I have very little on hand and will likely stick with the H110 base on what I have. The H110 were not bad just not as good. No leading of the gun fired 50 or so rounds.


The bottom groups were fired at 50 yards. The top was at 100 yards. I will have to get more comfortable with the AR platform and possibly work on the trigger if I am going to shrink the 100 yard group.

On a side note the brass catch I made does not look pretty but it beat hunting down brass.

 

[Winterborn]

I'm interested in this. Did you use gas checks when sizing?

I have a Lee 230gr 300 blackout mold that I haven't used yet, as I don't have the powder to cycle subsonic loads without a can as yet (anyone got any 1680 to spare? )

I'll probably go ahead and order the lighter mold as well.

 

[hvymax]

I'm interested in this. Did you use gas checks when sizing?

I have a Lee 230gr 300 blackout mold that I haven't used yet, as I don't have the powder to cycle subsonic loads without a can as yet (anyone got any 1680 to spare? )

I'll probably go ahead and order the lighter mold as well.

This is what I would go for for subsonics. I would gas check them out of GP but not out of necesity. You can reload for pennies like this.

 

[wgttgw]

Yes they are checked.

Alloy was some mystery hard lead that came from a stash of my grandfathers I found when cleaning out his garage after his death. Just guessing based of weight and properties of ingots/bullets I would say it is near the hardness of clip on wheel weight. The bullets were already cast for use in my sks or I would have used a known alloy. I am hoping to use this combo for deer season this year. My goal will be a load with 50% soft and 50% wheel weight for expansion if I wind up using this bullet for deer.

I am new the the caliber, so I don't know for sure, but do the subsonic loads need to be suppressed to cycle?

 

[Winterborn]

Yes they are checked.

I am new the the caliber, so I don't know for sure, but do the subsonic loads need to be suppressed to cycle?

Thanks for the info.

Yes, in my experience with H110, Lil gun, and 4227, I cannot get my rifle to fully cycle while shooting subsonics without a can.

I am desperately looking for some A1680, which I've been told (and read about) is the powder that Remington uses in its factory subsonic loads (300blktalk confirms this as well). I'm hoping that with this powder I can develop a load that will push a 230gr cast lead bullet at subsonic velocities, which means I can shoot my AR for the cost of 22LR or less, and be quiet to boot.

The ability to cast a supersonic bullet and shoot them reliably gas checked is attractive as well, and I'll be pursuing that shortly (mold you listed is backordered till sept on midwayusa) as well.

Thanks for the info.

Rich

 

[hvymax]

Wheel weight or similar lead,tin,antimony dropped into water will do fine in a subsonic load wich is far heavier than any sonic load. You need linotype(good luck finding that now a days)for any remotely sonic load.

 

[wgttgw]

Have you thought about 4198 or Rx7 for the subsonic loads. I missed out on that mold as it was sold out by the last time I received the email notification from Midway or I would try that myself. IIRC some guys are using them for subsonic, but I can't say if it was suppressed or not.

Wheel weight or similar lead,tin,antimony dropped into water will do fine in a subsonic load wich is far heavier than any sonic load. You need linotype(good luck finding that now a days)for any remotely sonic load.

Not trying to disagree with you or ruffle any feathers but that load above is using an air cooled alloy which is softer than clip on wheel weight. I have pushed air cooled gas checked wheel weight past 2100 fps with accuracy and no leading. At the very least I can say my rifles don't agree with what many feel about hardness.

 

[rickyp]

You need to be careful shooting cast bullets out of a gas operated rifle. The lube and lead will build up and block the gas ports and can collect in the gas tube.

 

[John from MD]

rickyp

"You need to be careful shooting cast bullets out of a gas operated rifle. The lube and lead will build up and block the gas ports and can collect in the gas tube."

That is true but shooting a couple of jacketed bullets after a session blows it right out.

wgttgw

You would probably get better groups with a mold made for a .308 bore diameter. Sizing .312 down to .309 doesn't help in the accuracy department.

I have been debating on building a 300 Blackout upper just for shooting lead as I make all my own bullets. All I need to get is getting a round tuit.

 

[rickyp]

Shooting a few jacket bullets after you shot cast bullets will not clean your bore. The copper will just smooth out the lead and push it deeper in and then cover it with copper fowling and powder.

 

[John from MD]

ricky

I did not say it would clean the bore, I said it will blow the lead out of the gas path. In my rifles, I don't get any lead in the bore due to proper sizing, a good alloy, good lube and gas checks.

The gas path and the BC of a AR type rifle does get lead build up and firing full power jacketed bullets will blow it into the BC where it can be cleaned with a carbon scraper.