Cast bullets in AR-15

[robert12345]

I do not own an AR-15 rifle, I may.....
I read articles, and watch videos of guys endlessly trying to get cast bullets to shoot through the .223 AR platform.

It's always the same:
Ping ping ping, ......They turn their AR rifle, into a very finicky .22 magnum, or the lead the hell out of it trying to duplicate jacked bullet velocities, with cast bullets.
.
The reason why the AR/.223 platform is not practical as a cast bullet rifle, is simple:

1.
The rifling twist is way too fast.
To shoot cast bullets fast, and accurate, a rifle needs a long twist, ...maybe 1/16, or better 1/18, ..not the "*** tight," 1/7 twist like we see in modern AR rifles.

Tight rifling twists simply "strip out" the lead bullet as it passes down the barrel.
You end up with a leaded barrel, a leaded gas port, a leaded chamber, and... the accuracy is ruined.

2.
The low powder charges needed at achieve accuracy, not only limit velocity, but, they also will not allow the action to cycle properly.

In the end, a guy shooting the "AR," with cast bullets, turns his rifle, into a finicky, bolt action 22 magnum, or he "leads" the hell out of it.
.
.
OK, an answer to the problem:

Maybe folks should consider, ....... a custom cast bullet wildcat cartridge , .....especially designed to shoot "cast" through the AR platform.

Folks could start with the existing .223 case, neck it up to .30 caliber, ..then cut the case back,,,, and push the shoulder back,,, until a 125 grain+/- cast bullet ( when seated ) will function through the standard AR magazine. That establishes overall cartridge length.
.
Next the bullet:
It needs to be long in the body, with a short pointed nose,, Lavern style, which has proven to give the best accuracy at high velocity.

The chamber throat:
It should to be made to fit that specific bullet, and only that bullet.

The rifling twist:
We look to the ...green hill formula..., that formula will tell us rifling twist for a specific bullet at a specific velocity, ...the longer the twist better, ...so maybe a 1/16 twist, or better 1/18...

Powder:
Would be case filling, and slow burning, ..and enough to cycle the action.
.
.
Velocity /accuracy/capability:
If properly done, a wildcat, on the AR platform, using the .223 cartridge case, could deliver velocities of around 2400/2500 fps (using quenched WW cast bullets) , ... have sufficient gas to properly cycle the action, ... deliver energy about equal to the AK-47, ......and do it accurately, out to and even beyond 200 yards.
.
.
OK, well, that is just my 2 cents, on shooting cast bullets using the AR rifle platform.

[Outpost75]

This Fouling Shot article cross-posted here by permission:


Cast in an AR? You Betcha! – By Ed Harris

If you reload for an AR platform, you know that ordinary 55-grain FMJ component bullets cost 10+ cents each when you buy in bulk, 1000-up quantities. Rifle powder costs upwards of $25 a pound if you still can find something suitable in this time of shortages. One pound of powder loads about 270 rounds of 5.56, so you are looking at about 10.9 cents per round just for powder. Buying 8 pound caddies can save you a little bit if you can find anybody who has them. Good luck with that.

Primers cost about $35+ per thousand, again, if you can find them.... So you are approaching 25 cents per pop in component costs alone to reload your "free" range pickup brass. That doesn't consider amortization of dies or equipment or put a value on your time to load the stuff. But it is lots better than $1+ per pop for factory stuff when you cannot find any...

An option is cast bullets! In a 5.56mm? Are you nuts?

Well, my neighbor is an avid reader of our CBA forum. He has learned “what works” by reading the gleanings from postings of other experienced shooters, which greatly shortened his learning curve. He has been shooting cast in his Colt LE-M4 clone for several years now. His has a 16" barrel with military 5.56 chamber. The military 5.56 chamber is larger in the neck and throat diameters than the .223 Remington. His M4 gas port is only 8" from the bolt face. QuickLoad, the interior ballistic computer program estimates his port pressure at ~ 12000 PSI. which is as low as you can go with (about 15 grains) of RL7 and still work the action reliably.

After 2,000+ rounds of cast practice loads accuracy equals or is better than the cheap Russian Tula FMJ ball ammo, the gas system shows no problems at all and the gun runs as clean with his cast reloads as with imported Tula ammo. The best use of cast loads is to preserve your expensive factory stuff for serious work...and to use your reloads for practice and casual shooting to save your Zombie Hoard!

He follows the advice of others, casting hard bullets, blending linotype from Roto Metals and wheel weights or backstop scrap 50-50, running his mold hot enough so that bullets drop uniformly frosted, then quenching uniformly frosted bullets in water direct from the mold. Gas checks are crimped on in a .225” sizing die so that the driving bands of the bullet are not sized at all. Bullets are seated as far out as they can be and still chamber freely, load into and feed reliably from the magazine.

His barrel twist is 1 in 9". Until recently he hadn’t tried any other powder than RL 7, because he keeps that around to load in his 7.62x39, which he also load casts for. Velocity is 2120 fps using 15 grs. of RL7 and the RCBS 225-55 gr. bullet.

This load performs well considering the generous military chamber dimensions. The major problem with shooting cast lead in AR's is their fast twist barrels in current rifles and their sloppy military chambers. Most folks who give up on cast in their ARs do so because they don't understand that the bullet surface which engraves ~ .002" deep simply does not have adequate shear strength to spin the bullet up in such a short distance without slipping the lands and damaging the bullet's integrity. Slow the load down to the minimum which cycles the action reliably, about 2100-2200 fps for most rifles, and they will shoot even better than steel cased Russian ball!

Computer modeling of slower powders such as Varget through QuickLoad, bullets lighter than about 68-70 grains, don't develop adequate port pressure at suitable velocities normally useable with cast bullets. Harder, quenched bullets can be driven 2400 fps without leading, but accuracy at this velocity is best in older 12-inch twist barrels, which limits you to flat based bullets no heavier than about 65 grains. In the 9" and faster twists stay below 2200 fps.

The computer-generated curves predicting pressure vs. bullet travel show that RL7 has the best characteristics to reliably function and efficiency is almost 100% with the powder being fully burned in a 16 inch barrel. A standard 20" length AR barrel is harder to make "work" as its gas port is further down the barrel than it is on the M4.

We did some accuracy testing in his M4 with his “standard load" of 15 grs. of RL 7 and the 55 gr. RCBS bullet, for which the double cavity molds are commonly available, and putting a scope on the rifle. Five-shot groups off sandbags at 100 yards averaged well under two inches in aggregate and were more accurate than the junky Tula FMJs.

Another LE visiting Peacemaker Training Center from DC brought his agency-issue Colt Military/law enforcement model with 7-inch twist barrel. We were pleasantly surprised to see it shoot a one hole 10-shot group of 3/4 inch at 25 yards. The load of 15 grains RL7 would occasionally would short recoil, ejecting the spent casing but without feeding another round. Additional experiments a 60-grain Saeco mold and 18 grains of H322 or IMR 3031 clocked 2100+ fps and cycled with no signs of leading. Bullets were lubricated with Lee 50/50 Alox-beeswax.

Adequate bullet diameter, not less than .225" is critical to accuracy. Load the largest bullet diameter that will chamber /function. Bullets must be of adequate hardness, not less than commercial 92-6-2 “hardball” alloy or 50-50 linotype and wheel weights, especially above 2200 fps. Heavier loads of slower powders such as Varget or 4895 may be needed to boost port pressure in full-length 20-inch ARs.

To load cast bullets without damage you must inside chamfer case mouths with a shallow-angle Lyman "VLD" deburring tool, and slightly bell the case mouths with a Lyman "M" die - so that the bullet can be hand started into the case mouth up to the top of its gas check and seated smoothly into the neck without risk of shaving lead. Then, during the seating operation apply a light taper crimp to remove all mouth flare, but not a heavy crimp which could deform the bullet.

Also drop-check all rounds 100% in a maximum length cartridge gage to ensure that they will chamber and extract freely. The same as required for any cast bullet load to be used in any semi-auto, AK, Garand, M1 carbine, M1911A1, etc.

The NOE http://noebulletmolds.com/NV/product...hiriq00hb97786 design is a good choice for either 10" twist, or faster twist barrels, with appropriate loads.

There are heavier custom molds available up to 75 grains, optimized for the 5.56mm military chamber, but I have no personal experience with them. Users on other forums report reliable functioning with 18 grains of IMR4895 or Varget for about 2000 fps with the MiHec 75-grain NATO bullet https://www.mp-molds.com/e-shop/sear...tribute_ids=22

[Harter66]

Ummmmm .
I had a 6.8 that shot amazing with cast .
I got 2150 fps with a 130 gr bullet , bested jacketed groups , and got to shoot it a lot at $14/100 instead of $60-80 .
Nominal speeds for a 130 jacket in 6.8 is 2300 so I did give up a little bit .

I only got about 2050 fps with a 62 gr cast in a 223 1-8" so there was a lot given up there but if you go on up to the 75-80 gr and make use of the twist you gain a great deal of ground back .

As for gas fouling I just never really saw it . I did get some chunks in the bolt once but it was a 5 min field fix.

The same rules apply .
Bullet fit .
Nominal bullet length/weight for twist .
Lube up to the task
Alloy up to the task
Nominally slower/lower pressure longer curve powders
Prep matching brass
Shoot well cast bullets

If it leads at the breach you need a bigger bullet
If it leads at the muzzle you need a different lube
If it leads in between you need a different powder or alloy or heat treat .

I know this will be shocking but jacketed powders and data work just fine with cast as long as you lean towards the slower powders and start low and work up . Work up . Start low and work up . Start with or just under start loads and work up .

[rancher1913]

ar's are very doable with cast, there are lots of threads of people having success. the pc coatings solve some of the know problems.

or you could make really nice 55 grain jacketed rounds with 22lr brass and a set of btsnipers dies.

[dogmower]

i shoot ar's in .223, 7.62x 39, 6.8 spc, 458 socom, 9mm, 10mm, 40 s&w, and 45 acp. all cast and powder coated. yet to have a problem with leading or with the gas system.

[Hamish]

Interesting.

Please, do tell us more robert12345.

[pkie44]

Interesting.

Please, do tell us more robert12345.

Sounds like he just described the 7.62 x 40 WT

[Thumbcocker]

Got some leading but only around the hole in the barrel for the as system. Could there be a burr on the inside of the barrel?

[Nines&Twos]

300 Blackout?

[leadman]

I've shot cast up to 3,000 fps in my AR15 with good accuracy. Better accuracy is had at 2,700 fps, equal to Federal American Eagle. No leading. Twist is 1 in 9.
Bullets were cast of linotype, heat treated, then Hi-Tek coated with minimal baking with water quenching after each of the 2 coats. Used Hornady gas checks. Aluminum did not work well at all, Gator checks did not hold the accuracy.
My Contender 23" barrel is a 1 in 12 and higher velocity over 3,600 fps is possible. I have posted about this before.

[clearcut]

Robert12345 I have one of those it's called a 300 blackout I use cast in it all the time .I also use cast PC'd gas checked in 1:7 .223 no problems.

CC

[Outer Rondacker]

I've shot cast up to 3,000 fps in my AR15 with good accuracy. Better accuracy is had at 2,700 fps, equal to Federal American Eagle. No leading. Twist is 1 in 9.
Bullets were cast of linotype, heat treated, then Hi-Tek coated with minimal baking with water quenching after each of the 2 coats. Used Hornady gas checks. Aluminum did not work well at all, Gator checks did not hold the accuracy.
My Contender 23" barrel is a 1 in 12 and higher velocity over 3,600 fps is possible. I have posted about this before.

Robert12345 I have one of those it's called a 300 blackout I use cast in it all the time .I also use cast PC'd gas checked in 1:7 .223 no problems.

CC

Whos bullet you casting and what size if you do not mind sharing. I have a RAR in 223/556 that is starving.

[bangerjim]

Fit is King!

You can shoot cast in anything as long as you follow the rules of fit.

I shoot cast/PC’d in all my bolt action Mossy’s all the time but ONLY FMJ commercial in my AR. Just saying......I do NOT like cleaning out ports and stuff!

[clearcut]

Outer Rondacker
In the 223 I use the NOE 225 62Gr. FN with the gas check and PC it comes out to 67 to 68 Gr.( my alloy WW, dental lead, solder, etc.)sized to .224 after PC. note : my wylde don't like them at all but likes the .22lr conversion kit both AR's are 1:7 . In the 300 BO I use the LEE TL309-230-5R with LLA lube @ 1090 fps. 1:8 twist.

CC

[Outer Rondacker]

Thanks clearcut. My RAR is a 1/8 it should do ok with a 62gr.

[Rcmaveric]

Cast bullets in 6.5 Grendel with NOE mold pushed to 2050 FPS works just fine and highly accurate. Cycled the action just fine. Just re-barreled the Grendel and don't expect any issues with this barrel either.

[corbinace]

I know this will be shocking but jacketed powders and data work just fine with cast as long as you lean towards the slower powders and start low and work up . Work up . Start low and work up . Start with or just under start loads and work up .

Hey Harter, just wondering where I should start on my load development???

[Motor]

I'm still looking for accuracy in the AR using the Lee 55gr but have zero issues with bullet failure even when not gas checked using powder coating.

I'm shooting the Lee 160gr 2R TL sub sonic from the 300 BO (purposely not working the action) but am about to test it super sonic without gas check. This bullet is also powder coated.

In my honest opinion the OP is at least out dated. Some good points are made though. I think an older AR with slower twist rate (How many of you remember these) would make a easier platform to work with.

Motor

[krallstar]

Sounds like he just described the 7.62 x 40 WT

Sure does. I have been reading up on this one and it seems to be a good choice. My son is looking into his first ar type rifle and this version is on the short list.

[Tracy]

It's not unusual to hear about all sorts of reasons why ARs don't make good cast bullet rifles... from those who have never tried it.
I shoot cast in 1:9" and 1:12" 5.56, a .300 BLK and a .50 Beowulf. The Beo has never had a jacketed bullet fired in it.

1:12" twist 5.56 AR barrels, while not the most common, are not difficult to find and work well for cast. Green Mountain also makes one with 1:14" twist, which is even better.
Some company used to make .222 AR barrels for the countries that prohibit civilian ownership of military calibers. I think that would be just about ideal.
I would like to have a 20" or 24", 1:14" .222 barrel with the gas port at the pistol position so I could use faster powders.