Lead Load Disbelief..

[meaty-btz]

I probably should ask on castboolits but I know some of us cast. I don't have the target photo but I recently decided to "up load" my 7.62x25 Powder Coated loads.

I pushed the load to 4.8gr of Red Dot, what I consider max for that powder. COL was 1.3. The load was measured by hand each time and within less than a .1 grain. The lead PC bullets weighed in at 94grains +/- 1 grain. I separated them out to get a narrow spread. Bullets were sized .310.

Now since this was at the indoor range I couldn't use my chronograph, but I estimate the velocity to be in the 1600fps range as the same load in 4.4gr is 1480-1490fps in lead while it was 1390s in jacketed rounds at 4.2 same weight range 110ish grains.

Recoil was, sharp, even stung a little. Now expected that I would lose accuracy. My lead alloy is almost eutectic with a melting point of about 450-475F, which can make Powdercoating melt-downs happen from time to time. So this lead is fairly soft being lead-tin-silver(trace). I don't use jackets and I do not use gas checks. This combined with the powdercoating being more slick than plain lead or copper means usually a more unstable bullet. In fact at 1600fps, even 1550fps I would start to think the soft alloy would be destabilizing.

It shot a 1" grouping with 20 shots at 12 yards CZ-52, off hand. As good as I can do, would need a ransom rest to gain on that. This is better than the lighter loads by far. Brass was being ejected over 20ft away.

So how can soft lead be driven so fast without it coming apart(powder coating does not add significant integrity to the bullet) or going inaccurate.

this is the opposite of what I expected. Of course the PC still works to prevent leading or any fowling (copper or lead) from being in the barrel only carbon.

Help me puzzle this one out. I intend to repeat the procedure out doors with the chrono to get a solid pin-point on the velocity. In the estimates catagory that puts the load at 534Ft/lbs of energy in a soft lead bullet. Woah. That is way more than I thought I could get out of a soft alloy.

[Swagman00]

Any flat primers?

A 30 cal doesn't have a wide diameter compared to most pistol bullets.

What mold did your pills drop from? A Lee 311-100-2R (What I use for my 7.62x25 loads) possibly?

Red dot also burns pretty quick too. That stuff is right up there with shotgun powder. The bullet could be deforming quickly with the ogive fully dug into the rifling, and before the base can fully melt, it's out the bore.

I was thinking of trying 7 gr blue dot with a 103gr pill (from said die above @ 12-13 BHN) sized to .311 lubed 50/50 alox/beeswax. My main concern is velocity.

I'd loan you my chrony to back up the numbers, but I'm likely too far.

[meaty-btz]

I've got a chrony, I just can only run it at the Pits. :\ Would love a second chrony to match numbers.

Anyways this is powder coated so there is no burn-through. Those PC bullets are SLICK, normally that means less stable.

And yes my brain is missing numbers, grabbed the wrong sheet. Stupid brain issue. ANyways.. nto 113 grains that was another load.. my 9mm!

These are the 93/94gr spread by my notes. I need to get a binder to keep everything off these loose slip papers. Size is .310 which is the size my gun likes best. that would be a 311-100-2r like yours.

I wouldn't go much above what I am doing, someone claims 5.5gr of reddot but that would be a compressed load with this large of a bullet.

FFS Now I feel like an idiot.. stupid grains, I will edit the original. Which is why the velocity is higher than the 110 grain speer hot-cors. DOH!

Fixed the numbers.

Anyways a day at the pits would be awesome with two chronos. I am going to try some copper plated because while the PC is cool, it is kind of a mess in production and I am working on a total coat rig for the PC and it is giving me fits. You know something to speed up production. The tinfoil just doesn't cut it.

Also, we are simply not supposed to be pushing lead this fast, but it sure does work.

No pressure signs AT ALL at that load level. The recovered brass showed normal primers and no other pressure signs, but was not what I would consider "comfortable" shooting. I might be able to push it higher in the grain loads but do I? I already am flinging the brass into the next county at 4.8 grains and 5 grains would be nearing a compressed load. Don't want a KB but making super slick-**** fast lead that is stable and accurate would be the bee's knee. Or something.

[Swagman00]

I've got a chrony, I just can only run it at the Pits. :\ Would love a second chrony to match numbers.

Anyways this is powder coated so there is no burn-through. Those PC bullets are SLICK, normally that means less stable.

And yes my brain is missing numbers, grabbed the wrong sheet. Stupid brain issue. ANyways.. nto 113 grains that was another load.. my 9mm!

These are the 93/94gr spread by my notes. I need to get a binder to keep everything off these loose slip papers. Size is .310 which is the size my gun likes best. that would be a 311-100-2r like yours.

I wouldn't go much above what I am doing, someone claims 5.5gr of reddot but that would be a compressed load with this large of a bullet.

FFS Now I feel like an idiot.. stupid grains, I will edit the original. Which is why the velocity is higher than the 110 grain speer hot-cors. DOH!

Fixed the numbers.

5.2 red dot is the highest number I've seen, but I don't think anyone has pushed 5. I wouldn't even think of using that a load that high in a CZ-52 to boot.

I'll have to powdercoat one of these days. I just get cheap with hardening and heat treat to kick the BHN to 16-18ish especially for higher velocities.

Good job none-the-less.

[meaty-btz]

5.2 red dot is the highest number I've seen, but I don't think anyone has pushed 5. I wouldn't even think of using that a load that high in a CZ-52 to boot.

I'll have to powdercoat one of these days. I just get cheap with hardening and heat treat to kick the BHN to 16-18ish especially for higher velocities.

Good job none-the-less.

The issue with powdercoating is finding a way to get total coverage that is "easy" and "time efficient". Just using the tray + foil works for partial coverage but.. that leaves something exposed. Either way without a pretty cool pin-clamp rig it is messy and slow which is why I am even willing to look into electroplating.

Again also the coefficent of friction on PC bullets is lower than plain lead, as such a bunch of people told me it would be less stable of a bullet, but that isnt the case.

[BruinGuy]

7.62x25 sure does zing!

I don't have any useful information for you about your loads, but I did chron some surplus (I think it's Polish). It is berdan primed, brass case, copper jacketed (not magnetic).

It was coming out at 1550fps. I don't know if the surplus is considered "hot" or not, but I don't think I'd want to try to get any more velocity in a load.

[3006mv]

Compare with plated bullets.
Maybe you bought magic fairy dust by mistake. Are you using acetone or lacquer thinner?

[stilly]

Compare with plated bullets.
Maybe you bought magic fairy dust by mistake. Are you using acetone or lacquer thinner?

NOOOOOOO! You did NOT just ask that here... Oh wait. NM. I get it. this is for info gathering only...
I bet he sprayed it on and not tumblecoated...



OP using jig or tumblecoating?

It was my understanding that you can push PC bullets to 3000+ FPS with no issues. Also, PC works on plated bullets too. I turned copper into blue.
I am going for two coats now to see how that makes things.

Also, check your bore for any PC left behind. My sources stated that there should be NO PC left behind, just a super slick bullet...

[meaty-btz]

There is no PC in my bore, clean up is easier than with jacketed bullets because there is no copper, just a light dusting of carbon. Once through with a damp patch and a once through with a dry patch and all clean.

yes, I sprayed it on. Tumblecoating got the "meh" from me very quickly. The jig for spraying gets complex, very fast. The only concern for me is that plating is easier but that PCing is "cleaner" for the gun, just more messy in production with more time being consumed on setup and cleanup. But with plating you get to clean copper out of the barrel.

[stilly]

There is no PC in my bore, clean up is easier than with jacketed bullets because there is no copper, just a light dusting of carbon. Once through with a damp patch and a once through with a dry patch and all clean.

yes, I sprayed it on. Tumblecoating got the "meh" from me very quickly. The jig for spraying gets complex, very fast. The only concern for me is that plating is easier but that PCing is "cleaner" for the gun, just more messy in production with more time being consumed on setup and cleanup. But with plating you get to clean copper out of the barrel.

I noticed something magical the other night.

I started with blue liquid a bit thinner then paste and it was running all over the bullets, then it poured out in a gloopy mess. TOO MUCH powder.

So I JUST put in some thinner the other night and started tumbling and low and behold, the bullets started turning color and the pigment was pulled right out of the suspension. The next thing you know I had CLEAR liquid and blue speckeled bullets, so I added more powder from a shaker and made the coating a bit thicker, but then when I poured it out, I still had colored bullets but clear thinner that came out.

I think the process should be to starve the liquid and add just a little of powder at a time, a little more and a little more until the coating looks good, then tumble and let it all dump out onto wax paper and seperate and fan, then once dry (several hours later) bake it on a bare metal rack, mesh for best results. But what do I know. I am still decoding this process.

[meaty-btz]

Have you managed to get that glass smooth look without pores or pitting with the "starve the beast" methodology?

The only way I could get smooth even coverage was with spraying, low velocity and then baking. Like I said, that is actually quite time consuming. But you get totally encased bullets that are smooth and shiny.

[Whiterabbit]

I So how can soft lead be driven so fast without it coming apart(powder coating does not add significant integrity to the bullet) or going inaccurate.

this is the opposite of what I expected.

Help me puzzle this one out.

In the estimates catagory that puts the load at 534Ft/lbs of energy in a soft lead bullet. Woah. That is way more than I thought I could get out of a soft alloy.

Now imagine the mushroom on that bad boy. No hollowpoint needed. Devastating.

But the answer is easy. You have been fooled for years by the jacketed shooters. You have been led to believe you need to tea-cup your lead bullets, treating them like delicate doilies to prevent problems when the reality is the opposite, as you hve now discovered.

What happened? I have a hypothesis, having experienced the same thing. I believe that by pushing them harder, you are obturating the bullet base even more, creating a better bore seal and more uniform internal ballistics. And are seeing the results of those uniform ballistics down range.

To complete the transformation, you can do what I did, and stop shooting jacketed bullets entirely. For all calibers, all cartridges.

[Whiterabbit]

Also, we are simply not supposed to be pushing lead this fast, but it sure does work.

If it works and is safe, then there is NO justification to not be doing it.

What, some barnes shooter on calguns told you you aren't supposed to push lead-tin alloys fast?

Sounds to me like whatever you are doing, to keep it up!

[meaty-btz]

If it works and is safe, then there is NO justification to not be doing it.

What, some barnes shooter on calguns told you you aren't supposed to push lead-tin alloys fast?

Sounds to me like whatever you are doing, to keep it up!

Naww it was castbooliters.

Do we have any hard data on twist+velocity that we lose bullet integrity because this would be awesome in 200 grains through my 8x57, powdercoated of course. Would drop my cost and be nice if I can throw 40-43 grains under a 200 grain powdercoated lead-tin bullet.

Earlier you asked about the mushrooming. I shot a metal target with one and it was captured. I don't still have the bullet because I could not recover it from the target (multi-layer target, bullet was trapped in the second layer) but I could measure it by what was visible. Over half an inch. It pancaked to a thickness I estimate to be less than 1/8th of an inch. So 545ft/lbs over .5" expansion from a .3 round. I think that would be effective. Don't know about bone deflection though. If anyone has some bone testing kind of setup I can load some and we can test to see if it skids or breaks through.

[Whiterabbit]

more fool, they.

I'm no expert on terminal ballistics, but I won't line up to get shot with a bullet that deforms like that.