Cast lead and the AR-15

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BigBore45

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Was thinking about getting a mold for .223. not much choice from Lee or Lyman. Was wanting a 80 grain bullet. Probably water quench WW lead and powder coat or hitek. Any molds out there at 75+ grains?
 
I would think that you would lead up the gas port. And maybe the tube too. The coating might limit it.
 
I'm running 440gr #2 lead w/ standard 50/50 ALOX:Beeswax in the Beowulf continually.
No problems at all -- including gas system.
 
I've run cast lead in gas guns before. With good hard bullets and powder coating, I had very little issues with leading in the bore or gas port. That was 7.62x39mm. I HAD a bunch of bullets in .224 size but gave them to another loader, never did try them in .223.
 
Ran some lead 405s thru my .458. No issues with the gas port or tube, crudded up my barrel pretty good tho.

Which would leave me expecting to see stuff in the gas system now that i think about it.
 
Cast bullets are rated by pressure to attain velocity. The BHN #22 Linotype or other high Antimony alloys with a gas checks and hard lube can with stand 15 " of barrel travel. It may attain a velocity greater than 2,000 fps before gas cutting occurs.
As the pressure over comes the bullet gases and heat escape around the bullet depositing "droplets" of hot alloy which adhere to the bore and gas ports. This is referred to as leading. The shorter barrels reduce the elapsed time of travel in the barrel. They may accept higher pressures before gas cutting occurs. Dropping Number II alloys BHN #7 in water is a temporary condition. The hardness begins to reduce significantly within 30 days. The bearing surface of the cast bullet and the barrels twist rate must be a consideration. This is a thumbnail report of cast bullets in the rifle. The CUP calculations are handy,

http://www.223reloads.com/home/cast-bullet-information/bhn-lead-harness-discussion
 
There's a whole bunch of folks over at castboolits.gunloads.com who've been doing it for some time. I do have to admit that Dog might be right about one thing - my cast loads in 7.62x39mm move less than 2000 FPS. With powder coating I find VERY little leading in my barrel, either gas or bolt.
 
I can advise that I've finally found some success with cast in my M1 Garand. WW and 50/50 WW/Lino alloys, powder coater or double powder coated, 150 and 200 grain, gaschecked.

Any softer, or HiTek coated, or un-gaschecked, and I wasn't even scaring the target at 50 yards, nevermind hitting it. The double powder coat seems to make up for 5-15 points of BHN lacking in the alloy.
 
Just yesterday, I ran a 110gr Lymnan 311008 (a plain-base using 15 BHN
/Lyman#2/50-50 ALOX/Beeswax) out of my 21" 32-20 Marlin 94 at 1,975fps.
Spotless barrel. 1.25" group at 50 using iron sights.

The Beowulf goes out at 2,350. Ditto (tho' w/ a gas check)

You don't have to lead up. You do have to fit the bullet/alloy to the weapon.
(and you aren't gong to push a cast/AR-15 up to jacketed velocities anyway.)
 
Cast bullets are rated by pressure to attain velocity. The BHN #22 Linotype or other high Antimony alloys with a gas checks and hard lube can with stand 15 " of barrel travel. It may attain a velocity greater than 2,000 fps before gas cutting occurs.
As the pressure over comes the bullet gases and heat escape around the bullet depositing "droplets" of hot alloy which adhere to the bore and gas ports. This is referred to as leading. The shorter barrels reduce the elapsed time of travel in the barrel. They may accept higher pressures before gas cutting occurs. Dropping Number II alloys BHN #7 in water is a temporary condition. The hardness begins to reduce significantly within 30 days. The bearing surface of the cast bullet and the barrels twist rate must be a consideration. This is a thumbnail report of cast bullets in the rifle. The CUP calculations are handy,

http://www.223reloads.com/home/cast-bullet-information/bhn-lead-harness-discussion
Thanks for the link.

I see an all to common error in MB formula calculation example here.

The CUP of your reloads is published in the reloading manuals. Take a typical .45 ACP load, using a 200-grain LSWC bullet – 5.0 grains of Bullseye. This load develops 900 FPS and is in common use among IPSC and IDPA gunners. The reloading manual shows that the pressure generated by this load is 20,000 CUP. So, the formula for optimal bullet hardness is

20,000 / 1279.8 = 15.62

SAAMI Max pressure for the 45 ACP is 18,000 CUP, so using 5gr of Bullseye will not generate 20,000 CUP. It may however generate 20K psi as the Max pressure for the 45 ACP measured in psi is 21,000 psi.

So if one is to use his formula one must understand that psi and CUP are different form of measuring the same thing and the are not interchangable, he obviously does not know the difference and that IMHO puts his formula in the "skeptical" file.

OH, according to Lyman 5.6gr BE generates 15,700 CUP, so his 5.0 gr generates nowhere near 20,000 CUP.
 
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Also, if we use MB's formula to calculate BHN for the 223 Remington we get this.

50,000 CUP/1279.8 = 39.06 BHN.

Anyone know of an alloy that will produce a bullet that hard?
 
MBC. BHN calculation is not right with my real world experience. It always seems to hard on his method. I run cast lead out of a .308 bolt gun with good success. That is why I was asking about heavier bullet molds in .225. I would think I could get a 80 grain bullet at 1900-2000 fps to cycle the action of the AR. Might have my first attempt at making my own mold coming..... I joined castboolits forum after visiting their site for years. But I will keep this over here on THR aswell.
 
Thanks men. I wanted serious and amiture bullet caster to study their hobby. Most people think a can of wheel weights and camp stove are all the science needed. But then they experience leading and inaccuracy. :)
 
MBC. BHN calculation is not right with my real world experience. It always seems to hard on his method. I run cast lead out of a .308 bolt gun with good success. That is why I was asking about heavier bullet molds in .225. I would think I could get a 80 grain bullet at 1900-2000 fps to cycle the action of the AR. Might have my first attempt at making my own mold coming..... I joined castboolits forum after visiting their site for years. But I will keep this over here on THR aswell.
Here is one you may be interested in.

http://noebulletmolds.com/NV/produc...ucts_id=901&osCsid=fm4siavaqt02405neqt4p84674
 
BB,

During the last great hording that ended about two years ago I was forced to learn how to shoot cast lead AR .224 rounds. I ended up putting 975 cast lead rounds through my LMT .223/556 with 1:7 twist with no leading of the barrel, gas tube or bolt. The only problem was getting any velocity over 2,000 f/sec as the bullets would break up into two pieces before exiting the barrel due to the rapid rotational forces. With the reduced velocity loads I did have to switch my buffer spring to a reduced power one from Wolf gunsprings to get reliable action cycling.

I used a NOE 70 grain mold which dropped 72 grain bullets and sized them to 0.225" and gas checked the bases and pan lubed (which is a real PIA). My alloy as tested by Rotometals was 97.18% lead, 2.22% antimony and 0.435% tin. MY BHN hardness after water dropping in 70 degree water was about 15 and would go up a bit if I used ice water.

I experimented with adding more tin and even copper to the alloy but could not get enough increased velocity above 2000 f/sec to justify the cost and time involved.

So the answer to the question of whether you can successfully shoot .224/556 out of your AR is yes but don't expect the same performance as an FMJ round.

good luck-oldandslow
 
BB,

During the last great hording that ended about two years ago I was forced to learn how to shoot cast lead AR .224 rounds. I ended up putting 975 cast lead rounds through my LMT .223/556 with 1:7 twist with no leading of the barrel, gas tube or bolt. The only problem was getting any velocity over 2,000 f/sec as the bullets would break up into two pieces before exiting the barrel due to the rapid rotational forces. With the reduced velocity loads I did have to switch my buffer spring to a reduced power one from Wolf gunsprings to get reliable action cycling.

I used a NOE 70 grain mold which dropped 72 grain bullets and sized them to 0.225" and gas checked the bases and pan lubed (which is a real PIA). My alloy as tested by Rotometals was 97.18% lead, 2.22% antimony and 0.435% tin. MY BHN hardness after water dropping in 70 degree water was about 15 and would go up a bit if I used ice water.

I experimented with adding more tin and even copper to the alloy but could not get enough increased velocity above 2000 f/sec to justify the cost and time involved.

So the answer to the question of whether you can successfully shoot .224/556 out of your AR is yes but don't expect the same performance as an FMJ round.

good luck-oldandslow


Thanks you. I'm fully aware of the velocity restrictions. as i load a lot of cast 308 win. I just want the action to cycle. which seems pretty doable. Also the heavier the bullet the closer i can be to factory Velocity. i have not had any luck with accuracy much past 2000 FPS with lead cast bullets. so if i run an 80-90 grain bullet i will only be 300-500 FPS slower than jacked loads. i can easily mix some Linotype lead with WW lead and water quench to make sure to get to 2000 FPS without leading. i will do some testing.

I have decided to make my own bullet mold. I ordered the Lee 55 grain 2-hole mold and plan on removing the gas check and lube groove rings and extending the mold with a different nose profile. My goal is to be around 90 grains with strait WW lead and powder coated. I will keep this posted. Might start a new thread on the mold build. but will report back with accuracy and function of the action. I always forget to take picks or videos when i do this stuff but im going to try this time.
 
Well i got the mold in Monday. Cast about 75 bullets and Hi-Tek coated them 3 times. Went out with some test rounds. First was a known load out of the Lyman 49th with 4227. it obviously didn't cycle the action but i wanted to check for leading and accuracy. shot about 1" group at 50 yds and had zero leading at 1950 FPS.

Ok. on to the high velocity stuff. Im running the lee 55 gr. bator bullet right now at 14 BHN ( what was in my pot ), and coating with 3 coats of Hi-Tek. started at 20 gr. IMR 4064. shot fine @ 2050FPS, however would not cycle action. went up to 23 grains of IMR 4064 before the action would cycle and going across the crony at 2450 FPS. got a bit of leading after 30 rounds at the muzzle end, im sure the lube is coming off. Accuracy at 50 yards with the 23 gr. load was not good about 2.5" at 50 yds. So this mold is not going to work at 55 grains. im going to get it in the mill and get rid of the gas check shank, lube grooves and change the nose profile. going for an 80 grain bullet. I know i can just make the BHN up gas check it and do 4-5 coats but you get to a point were getting 18-22BHN and gas checks and extra coats cost to much money and causes me to buy another pot to keep separated from my pistol lead. All that defeats my purpose of cheap cast for the ar-15.
 
Just as a point of reference my 300 Blackout AR has at least 4000 rounds of cast lead through it and the gas system is still working exactly the same as it did for the first round. If my gas tube is going to fill up with lead it would seem that it's not in any hurry.
 
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