Bator 223 cast bullets ( cont.)

[Dancing Bear]

I had put my quest for accurate and reliable functioning Lee Bator bullets for the AR platform on the back burner a while back. Never got great grouping with the milder loads I tried.
Now that I started powder coating other calibers I want to try pc'ing the Bators as well.
Should I even gas check? I see some gc before pc, some after, but is it necessary with pc at all?

[Moonie]

Gas check designed bullets are more accurate with checks, even when powder coated. I gas check after powder coating.

[sigep1764]

What twist is your barrel? If it’s 1/8 it might work, 1/9 definitely if sized right. If it’s 1/7, you might be in trouble. If it doesn’t work, pm me and I can send you some 70 ish grain cast PCed Boolits to try.

[waksupi]

I would definitely use gas checks. The .223 bore size is already one of the most finicky to get shooting well at higher velocities.

[405grain]

When I'm trying out a new bullet I powder coat just one of them. Then I take that powder coated bullet, and one that's bare, and seat a gas check onto each of them. That way I can find out if I should install the gas check before or after powder coating on that particular bullet. If the powder coating makes the check hard to seat, I know that I should install the checks before coating. If the checks are kinda loose on the shank of the bare bullet, then I'll powder coat before installing the checks. Try it out and see which way works the best for you.

[stubshaft]

I had problems with the shank size in two of the Bator molds I had. Both had one that was too parge and one that was undersize for the GC. I cured that buy milling off the GC section (which reduced it to 45 grains) and using it in my K-hornet where it shoots great.

[Dancing Bear]

What twist is your barrel? If it’s 1/8 it might work, 1/9 definitely if sized right. If it’s 1/7, you might be in trouble. If it doesn’t work, pm me and I can send you some 70 ish grain cast PCed Boolits to try.

Thanks guys. Gas checking it is then.
Sigep1764 thank for the offer but if I remember correctly, when I tried jacketed 77's I had bad accuracy. I believe my twist is 1:9. My silicon mini ice cube trays are due to arrive tomorrow and I hope to pc and load up a trial batch. Getting to the range this time of year is another story however.

[Land Owner]

PC'd a batch of Bators with checks. Ladder loaded them up to jacketed bullet velocities - wanting AR platform cycling mostly, but using a single shot Handi-rifle with bull barrel for testing first. Results were "not as hoped". As velocity increased rounds failed to reach the target at 100 yards.

"Poof" - centripetal disintegration (I think) of 49-49-2 percent Pb-WW-Sn 12 BHN cast lead. Have not followed up since. Still "not happy" with either 50 (+/-) grain Bator or RCBS 22-55-SP in either 1:9 bull barrel or 1:12 standard barrel Handi-rifles.

[Larry Gibson]

Not necessarily "centripetal disintegration" but more likely the result of excessively exceeding the RPM Threshold. The bullet probably maintains stability (still flying nose forward) but flies off at a severe tangent to the line of flight because of the centrafugal force acting on the bullet imbalances. I discovered that years ago after cast bullets were not hitting a normal size target at 100 yards. I was using the 225462 gast of linotype and WQ'd in a 6" twist Colt AR15. If I recall correctly the velocity was above 2400 fps when the bullets began completely missing a normal size 100 yard target. I could see the impacts in the berm all around the target. I put up a full size 200 yard NMC target at 100 yards and was able then to "catch" the bullets on target. After a ten shot test all bullets had made nice round holes in the target. That showed the bullets still maintained stability.

[Land Owner]

Always the exception, I was shooting at a 72-inch by 54-inch white board at 100-yards. Starting with targeting the center, then targeting each corner. Nothing found the target after a certain point in increasing powder charge. Left me head scratching...

[Larry Gibson]

Always the exception, I was shooting at a 72-inch by 54-inch white board at 100-yards. Starting with targeting the center, then targeting each corner. Nothing found the target after a certain point in increasing powder charge. Left me head scratching...

Absolutely!

What is the Twist on that AR?

Any idea of the velocity?

[Land Owner]

Have not checked the twist of the AR (yet)

Handi-rifle bull barrel twist 1:9
Win 748; ladder loaded 23.8 gr. (2900 fps) to 25.8 grs. (3100 fps) in 0.5 gr. increments
(I know - jacketed loads)
55 gr. RCBS 22-55-SP
(I know - not a Bator)
49-49-2 percent Pb-WW-Sn alloy
GC & PC w/Smokes Bacon Grease Yellow
Velocity in the range of 3,000 fps
(I know - jacketed)
trying PC alloy for AR-15 platform cycle performance
boolits failed to arrive at target in single shot Handi-rifle testing.

Kind of expected...nothing ventured, nothing gained.

[Larry Gibson]

With a 9" twist at 3000 fps the RPM is 253,333. With a 7" twist it is 325,714 RPM. With either that is a lot of RPM/centrifugal force exerted on those soft alloyed cast bullets. They probably are coming apart in flight. Might try slowing them down with another powder to 1800 - 2000 fps keeping the RPM down at 140,000 +/-. Also, might try your COWW + 2 w/o the Pb added and WQ or HT them.

FYI, 3000 fps in a 12" twist is only 190,000 RPM which is why I only shoot cast in my 12, 14 and 16" twist 22 cal rifles anymore. The difference in RPM from the varied twists of different 223/5/56 rifles is why the performance of cast bullets in such is so varied. Also, many who just "blast" out to 100 yards max with their faster twist ARs find velocities of 2000 - 2500 fps gives "acceptable" accuracy if the bullets hold together.

While my 12 and 14" twist 223 bolt guns and SS will give better accuracy here is the load that does about the best in my 12" twist AR with 20" barrel and an EoTech sight. Not even as good as US M193 ball but good enough for practice. Targets are at 100 and 200 yards. Note the pretty much linear expansion between 100 and 200 yards. That is indicative the load is under the RPM Threshold.





My 12" twist M700V (before it was shot out) and M70 XTR would give close to 1 1-1/2 moa accuracy at 2300+ fps with 225462 and 225438s cast of #2 alloy and WQ'd. Conversely my 9" twist Savage Competition and Colt AR Competition would only do so when the velocity was at 1900 fps.

[Dancing Bear]

Not the best picture but: I ended up pc'ing 5 bullets first and then gas checked them kind of as advised. Looked good so I went ahead and did a batch of 69. Probably 95% of the gas checks "snapped" onto the bullet bases. A few I had to play with, probably due to some extra pc on the edges. then I ran them through the Lee sizer die. Can't wait to do some shooting with them.
Thanks again for all the input guys.

[Land Owner]

Nice job D_Bear. Good color choice. I hope you find reliable function and an accurate load with those in your AR.

I don't shoot GC boolits through my chrono, though, for velocity, I will shoot a GC shaped boolit through, without its GC. I don't want to purchase a new sky screen or find the chrono damaged from a GC coming off in flight...ymmv.

Larry - great dialog and data. TY. I had not thought about the RPM's though I can calculate 'em. I will continue to exercise the 1:12 Handi-rifle with WQ and PC'd cast at or below 2000 fps to see where that leads in both Bator and RCBS 55-22-SP. I will probably migrate to jacketed bullets (sacrilege) in the 1:9 Handi-rifle (3000+ fps) or slow them down 1/3 and try again with cast. For the AR, I'll check the twist and decide which way to go from there.