Cast boolits in 300bo

I think it depends alot on how fast you want to push them. Ive looked for quite awhile for a 150ish grain HiTek coated bullet that will run in a 300 BO, and have never found one in production. When I say will run in 300 BO, I mean it needs to have a reasonable point to the bullet. Both Acme and MBC make 155s, but they are RNFPs, which generally dont feed all that well without feed ramp modifications from everything I have read. HiTek coating is good for 1800ish FPS and if you gas check the bullet probably more. If I shot 300 BO alot, I would certainly look at some of NOEs mold offerings in the 145-155 gr range, and pick up a mold or two and give them a try. But for now, I just shoot 150 FMJs and 125 Speers. If you want to go subsonic and you are just using it as a range toy, I see no purpose in running those 220+ gr monsters. A 180-200 will run as a sub all day long.

AJC1 said:

I've seen some people have issues with cast in 300bo and end up with lead rings in their leade and other weird issues. Are there people out the also having issues, is this likely a one of, or what. I intend this to be my next project in a 16" ar and was curious on the successes, failures and lessons learned.

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I've shot quite a few. The Gallant 220, the ACME 265 ds, and the MBC 245. All coated. Hundreds, maybe thousands. All sub in a 10 or a 7.5. No leading issues, no gas port issues, all with a can. Accuracy is not what I get with jacketed though. Just seems a limitation of the platform there. The 265 DS was the most accurate. All performed better than Berry's 220 plated. None of them could touch a Sierra 220 SMK, which is the gold standard for sub 300blk accuracy IMHO. Gallant was the cheapest...I think the last batch I bought was like .07 ea, but that was a while ago. The heavies need either a Magpul 300 blk pmag, or mods to a GI mag. Standard unmodified mags are hit and miss with heavies, may or may not be reliable. The 300blk pmags are 100%. I've never messed with cast supers...I buy bulk 150 fmj in 5k ct cases for my garand, ar10, and 300blk so never occured to me to go that route. I'm going to follow this with interest to see what folks say.

I loaded up some using Lee 309-150f mold coated with hi-tek. Not many though, makes more sense to me to just cast 147 gn 9mm bullets because they use much less powder for playing around.

AJC1 said:

I have a nice 165 that I want to run. Just a range toy really no can plans...

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I used that RCBS 165 Sil using 3031 in a Ruger Bolt gun worked good but only tested out to 100 yards. (don't do AR's)

For cheap plinking subsonic 300 BO I like Barry's 220gr spire point. One of these days I am going to try some even heavier cast bullets but if I do it will be coated lead, not bare led. But the Barry's are only a little bit more expensive and so much cleaner and easier.

X2 for 220gr Barry’s.

I tried a number of different 300 BO barrels in ARs (6.5", 7.5", 8.5", 10.5" & 16") trying to get one that would shoot my cast reasonable well. All were PC, some were gas checked, some were plain base. Bullets were 126 gr, 150 gr, 156 gr, 165 gr, 175 gr & 180 gr. Loads were supersonic. Some cycled ok, some did not. None shot well.

Also note that PC does not seem to do a good job of protecting the base as it passes the gas port. I had significant lead buildup issues in the bolt area using plain base.

The only upper that I have been able to get good performance from with cast is 35 cal.

Haven’t gone down the cast road yet for my .300 BO SBR.

Quick question for the group. Is shooting lead bad for suppressor or is it a non issue?

Lennyjoe said:

Haven’t gone down the cast road yet for my .300 BO SBR.

Quick question for the group. Is shooting lead bad for suppressor or is it a non issue?

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Uncoated lead is going to make lead and carbon build up faster in the suppressor than coated or jacketed does. Doesn't hurt it but will make build up happen faster. Probably a bigger issue for cans that don't come apart for cleaning. My own is a welded can so I will be skipping the uncoated lead just to prolong that cleaning requirement as it is going to be a messy poisonous pain in the arse.

mcb said:

Uncoated lead is going to make lead and carbon build up faster in the suppressor than coated or jacketed does. Doesn't hurt it but will make build up happen faster. Probably a bigger issue for cans that don't come apart for cleaning. My own is a welded can so I will be skipping the uncoated lead just to prolong that cleaning requirement as it is going to be a messy poisonous pain in the arse.

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Meh, I've decided the need for a can that comes apart for cleaning is more a myth perpetrated by the makers of cans that come apart for cleaning, lol. If you need to clean a can.....a mag dump of 5.56 through it, and that sucker is spotless! If it's a pistol can...+p 9mm pretty much accomplishes the same thing. My supporting data: I weigh all my cans when new, because somebody told me I needed to do that so I would know when they are leaded up. Some of them are now more than a decade old....with 100's of thousands of rounds through them. And that includes plenty of cast 45 ACP, 9mm, 45 Colt, and 38 SPL. Whatever I felt like shooting...cast, plated, coated cast, didn't matter. The only one that ever got measurably heavier was my 9mm Osprey, by like a 1/10th of an oz. But after shooting +p 115's from a 10inch carbine one afternoon, it lost all that weight;-) I also quit taking apart my rimfire cans...cleaning them was just a waste of time. Taking them apart after 10,000 rounds...they look exactly the same inside as taking them apart after 100 rounds. So now I don't care anymore...I just shoot whatever I want and don't worry about it. I quit shooting straight cast though, not because of the can, just because Hi-Tek is so far superior in every way there is simply no reason to subject yourself to cleaning bullet lube out of your proggressive, dealing with leading, or simply exposing your self to handling plain lead. To me, the only reason to mess with straight cast is because it's something you as an individual are passionate about, and that's something you do as part of your shooting experience. If you're purely a shooter, and not passionate about cast or casting......it just ain't worth it IMHO....buy hi-tek coated bullets.

Just getting into reloading 300 BO with a 10 inch barrel. So far no suppressor but watching this with intrest. Am unsure about lead projo's.

mcb said:

Uncoated lead is going to make lead and carbon build up faster in the suppressor than coated or jacketed does. Doesn't hurt it but will make build up happen faster. Probably a bigger issue for cans that don't come apart for cleaning. My own is a welded can so I will be skipping the uncoated lead just to prolong that cleaning requirement as it is going to be a messy poisonous pain in the arse.

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Mine as well (AAC Cyclone)

P Flados said:

I tried a number of different 300 BO barrels in ARs (6.5", 7.5", 8.5", 10.5" & 16") trying to get one that would shoot my cast reasonable well. All were PC, some were gas checked, some were plain base. Bullets were 126 gr, 150 gr, 156 gr, 165 gr, 175 gr & 180 gr. Loads were supersonic. Some cycled ok, some did not. None shot well.

Also note that PC does not seem to do a good job of protecting the base as it passes the gas port. I had significant lead buildup issues in the bolt area using plain base.

The only upper that I have been able to get good performance from with cast is 35 cal.

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I wanted to read through this carefully but this fine gentleman hit the point I was going to make. Just like shooting cast bullets through a ported pistol barrel, you have to break that barrel in VERY well or risk closing your gas port. Go heavier 180-200 grains and try to keep your velocities below 1450-1500 fps.

The fix is to shoot gas check. But I never liked shooting them. So I just shoot the snot out of it with jacketed(the steel case bimetal bullets are best). Then clean the barrel thoroughly then start cast lead development.

And pick a coating that will make the ride down the barrel without skidding. I only use powder coated bullets as Hi tek can’t handle that kind of velocity/ pressure unless shooting from the cleanest of barrels.

You will know if something’s not working right if you’re seeing silvery metal flecks on your muzzle device.